Ebook Emergency medicine procedure (2nd edition): Part 2

SECTION

Skin and Soft Tissue Procedures

92

General Principles of
Wound Management
Lisa Freeman Grossheim

INTRODUCTION
An acute wound can be defined as an unplanned disruption in the
integrity of the skin, including the epidermis and dermis. The goals
of wound management are to restore tissue continuity and function, minimize infection, repair with minimal cosmetic deformity, and be able to distinguish wounds that require special
care. The principles of wound management should be emphasized
over the repair technique. Appropriate wound management prior
to approximating the wound will allow it to heal with minimal
complications. This includes wound cleansing, debridement of the
wound edges, wound approximation, and prevention of secondary
injury.

HEALING OF WOUNDED TISSUE
PHASES OF WOUND HEALING
The response of tissue to an injury is described in three phases. The
first phase is coagulation and inflammation. The second phase is
the proliferative phase. The final phase is the reepithelialization or
remodeling phase.
Phase I consists of coagulation and inflammation. It occurs in
the first 5 days. This phase is also known as the vascular phase. A
fibrin clot forms a transitional matrix that allows for the migration
of cells into the wound site over a period of 72 hours. Inflammatory

cells (i.e., neutrophils, monocytes, and macrophages) kill microbes,
prevent microbial colonization, break down soluble wound debris,
and secrete cytokines. The cytokines signal synthetic cells, such
as fibroblasts, to initiate phase II. Most sutured wounds develop
an epithelial covering that is impermeable to water within 24 to
28 hours.
Phase II is the proliferative phase. It occurs during days 5 to
14 after the injury. Fibroblasts proliferate and synthesize a new connective tissue matrix that replaces the transitional fibrin matrix.
Granulation tissue consisting of fibroblasts, immature connective
tissue, epidermal cells that have migrated, and abundant capillaries
forms within the wound. Fibroblasts release collagen, a protein substance that is the chief constituent of connective tissue. At 5 days,
the tensile strength of the wound itself is 5% that of normal skin.
Collagen formation peaks at day 7.
Phase III is known as the remodeling, reepithelialization, or maturation phase. It occurs from day 14 and lasts until there is complete
healing of the wound. The new granulation tissue is being converted
into a scar. The scar consists of a rich matrix with decreasing cell
density, decreasing vascular density, and increasing thickness of
collagen fiber bundles packed in parallel arrays.1 The wound will
have 15% to 20% of its full strength at 3 weeks and 60% of its full
strength at 4 months. Tensile strength continues to increase up to

7

1 year after wounding. The skin will eventually regain only 70% to
90% of its original tensile strength.

FACTORS AFFECTING NORMAL REPAIR
The most common causes of improper wound healing are tension on
the wound edges, necrosis and/or ischemia of the tissues from local
conditions (e.g., crush injuries and contusions decrease blood flow

and lymphatic drainage, which alters local defense mechanisms),
or shock. Hypovolemia is the major deterrent to wound healing in
patients with hemorrhage and shock, hemorrhage from inadequate
hemostasis, infection, or retention of foreign bodies. Systemic conditions such as malnutrition, immunosuppression, shock, diabetes secondary to microangiopathy, decreased oxygen and nutrient
delivery to the wound, renal insufficiency, cytotoxic drugs, vitamin
deficiency, trace metal deficiency, and collagen vascular disease can
result in poor wound healing. Polymorphonuclear leukocyte function is known to be impaired from hyperglycemia, jaundice, uremia,
cancer, or chronic infections.
Drugs and medications can contribute to good wound healing or
affect it adversely. Malnutrition, lack of protein, and lack of vitamins (e.g., vitamins A and C) may inhibit or prolong healing. Zinc
deficiency, which is reversible, may play a role in retarding the healing process.3 Anti-inflammatory drugs (e.g., colchicine, aspirin, and
glucocorticoids) disrupt macrophage function, collagen synthesis,
and polymorphonuclear neutrophil concentrations. Pretreatment
or early introduction of glucocorticoids results in retarded wound
repair by slowing cell proliferation.4

SCAR FORMATION
Some 6 to 12 months are required to form a mature scar. This
explains why scars should not be revised until 12 months have
passed. A wider scar, inadequate wound closure, or a wound dehiscence may occur in areas with increased skin tension or if the
wound is in an area of excessive motion (e.g., over joints). Adequate
immobilization of the approximated wound (but not necessarily
the entire anatomic part) is mandatory after wound closure for
efficient healing and minimal scar formation. Contractures can
develop when a scar crosses perpendicular to a joint crease. These
patients may require physical therapy to prevent the loss of range of
motion secondary to contractures.
Hypertrophic scars result from full-thickness injuries. Hypertrophic scars are characterized by a thick and raised scar that
remains within the boundaries of the original injury. They must
often be corrected by surgical intervention.1

Keloids are hypertrophic scars (i.e., thick and raised) that
exceed the boundaries of the initial injury. They can develop
from superficial injuries and appear to have a genetic basis. Surgical
intervention rarely resolves keloids. They may be prevented or
minimized by the local application of pressure dressings, Silastic
dressings, glucocorticoids, and calcium channel blockers.1
The repair procedure may result in more scar tissue. Absorbable
suture materials contribute to the formation of suture marks because
of their increased reactivity, whereas nonabsorbable materials do
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SECTION 7: Skin and Soft Tissue Procedures

not. Wounds that are approximated too tightly can result in tissue
ischemia and more scar tissue formation.

WOUND CLOSURE TECHNIQUES

clean the wound. Scrub the wound base and edges with salinemoistened gauze and irrigate the wound to remove any dirt,
debris, and granulation tissue. Suture the wound to approximate
and evert the wound edges. The postprocedural wound care is
the same as if the wound was closed primarily.

PRIMARY INTENTION
Primary intention involves surgically approximating the wound
edges shortly after the time of injury. The skin’s greatest strength
is in the dermal layer. The best repair results when the entire depth

of the dermis is accurately approximated to the entire depth of the
opposite dermis. Accurate approximation of the epidermis gives a
cosmetically appealing effect to the repair but does not contribute to its strength. Wound eversion and the use of buried sutures
can greatly improve healing by primary intention.

SECONDARY INTENTION
Secondary intention involves allowing the wound to heal without
any surgical intervention. The wound is left open and allowed to heal
from the inner layer to the outer surface. It is a more complicated
and prolonged healing process than primary intention. Infection,
excessive trauma, tissue loss, or imprecise approximation of tissue
can result due to healing by secondary intention. Wound contraction by granulation tissue containing myofibroblasts is the major
influence on this type of healing. Wound contraction becomes more
significant when the dermis is lost.
Concave skin wounds heal with the best results. These areas often
heal better by secondary intention than by primary intention. Such
concave areas include the inner ear, the nasal alar crease, the nasolabial fold, the temple, and the concave areas of the pinna. Flat surfaces can also heal well by secondary intention, although surgical
intervention may be best. Some examples include the forehead, the
side of the nose, and periorbital areas. Wounds on convex surfaces
are not optimal for healing by secondary intention. Convex surfaces
include the malar cheek, the tip of the nose, and the vermilion border of the lip.2

TERTIARY INTENTION
Tertiary intention, or delayed primary closure, can often decrease
infection rates. Wound closure by tertiary intention is accomplished 3 to 5 days following the initial injury. It is a combination
of allowing the wound to heal secondarily for 3 to 5 days and then
primarily closing the wound. It is the safest method of repair for
wounds that are contaminated, dirty, infected, traumatic, associated with extensive tissue loss, at high risk for infection, and for
wounds that are “too old” to close. The ultimate cosmetic result is
the same as that of primary wound closure. This method may not

be suitable for young children, having to return a second time for
an uncomfortable procedure.
During the interim period, instruct the patient to apply wetto-dry dressing changes twice a day. Upon the patients return,
assess the wound for any signs of infection. Anesthetize and

WOUND INFECTION
Wound infections occur as a result of the patient’s resident flora and
the environment. It is related to wound age, the amount of devitalized tissue, and the tissue concentration of pyogenic bacteria. A
wound infection exists when there are bacterial densities of more
than 10,000 organisms per gram of tissue.5 Bacteria slow wound
healing by secreting proteases that directly injure the tissue in the
wound.2 They also secrete other factors that lead to excess inflammatory cells in the wound, which also injures the tissue.2

PATIENT EVALUATION AND ASSESSMENT
HOST HISTORY
A thorough and accurate history and physical examination are
essential for optimum wound management. Documentation of the
patient’s age, prior tetanus immunization history, systemic illnesses,
medications, allergies (such as to latex or local anesthetics), and
the circumstances of the injury are essential to good wound management. These principles are emphasized because the presence of
disease processes (such as diabetes mellitus, chronic malnutrition,
alcoholism, hepatic or renal insufficiency, asplenism, malignancies,
and extremes of age) may impair host defenses or complicate wound
healing.6,7 Second, the wound itself is often less important than an
associated injury to an adjacent structure or cavity. Associated
injuries can easily be missed without a specific directed search
for their presence.

TETANUS PROPHYLAXIS
A thorough history must be obtained concerning the patient’s tetanus immunization status. Important factors to consider in assessing

the risk of developing tetanus include prior immunization history,
the type of wound, the degree of wound contamination, the time
from injury to treatment, and the presence of underlying medical
disease.
Wounds may or may not be prone to tetanus (Table 92-1).
The administration of tetanus prophylaxis is based upon the
patient’s immunization history and the risk of developing tetanus
(Table 92-2). Current guidelines state that tetanus toxoid (Td) may
be deferred in patients with “clean, minor” wounds who have completed a primary series or received a booster dose (Td 0.5 mL IM)
within 10 years. Consider tetanus immune globulin (TIG 250 to
500 U IM) in addition to Td for patients at risk of developing tetanus. Elderly patients without documentation of a primary series,
patients from nonindustrialized nations, and those from rural or

TABLE 92-1 Characteristics of Tetanus-Prone and Non-Tetanus-Prone Wounds
Clinical feature
Tetanus-prone wounds
Contaminants (feces, foreign body saliva, and soil)
Present
Devitalized tissue
Present
Infection
Present
Ischemic or denervated tissue
Present
Mechanism of injury
Burn, crush, bullet
Wound age
>6 h
Wound depth
>1 cm

Wound type
Abrasion, avulsion, crush, irregular, stellate

Non-tetanus-prone wounds
Absent
Absent
Absent
Absent
Sharp and smooth (knife or glass)
<6 h
<1 cm
Linear or straight


CHAPTER 92: General Principles of Wound Management
TABLE 92-2 Tetanus Prophylaxis
Immunization history
History of adsorbed Td
Unknown or less than three doses
Fully immunized, >5 years and <10 years since last dose
Fully immunized; ≤5 years since last dose
Fully immunized, ≥10 years since last dose

Tetanus-prone wounds
Td and TIG
Td, TIG, and complete the series
Td
None needed
Td and TIG

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Non-tetanus-prone wounds
Td and TIG
Td and complete the series
None needed
None needed
Td

Td, tetanus and diphtheria toxoids; TIG, tetanus immune globulin.

inner-city areas may never have received tetanus immunization and
should be considered for TIG.

MECHANISM OF INJURY
Severity of injury as well as associated injuries can be anticipated by
determining the precise mechanism of injury. This will often indicate additional soft tissue injury, the presence of a foreign body, or
the amount of contamination present.
Soft tissue injuries are rarely surgical emergencies. The patient’s
general condition should be attended to, with priority given
to observing the ABCs (airway, breathing, and circulation) of
Emergency Medicine. The skin margins of a laceration can be
tacked together with well-placed atraumatic sutures and the wound
covered with a moist pressure dressing until the time is more opportune for definitive repair.
Important questions and answers that must be documented
are exactly how the injury occurred, when and where the injury
occurred, and what contaminants were present or involved. If the
injury involves the hand, what position was the hand in at the time
of the injury, what kind of work does the patient do, and which is
the patient’s dominant hand? Complicated wounds, such as those

caused by animal or human bites, chemical exposure, or highpressure injection may require a more extensive evaluation and
consultation with the appropriate specialist.

CLASSIFICATION OF WOUNDS
Wounds are described and classified based upon their cause and
the type of injury. Abrasions are the result of grinding or abrading
forces on the skin. The epidermis and/or dermis is disrupted but
not removed in its entirety. Crush injuries are due to compressive
forces. The patient sustains a large amount of kinetic energy that
results in microvascular disruption, edema, and devitalized tissue.
Crush wounds are 100-fold more likely to become infected than
lacerations because of the much lower bacterial loads required for
infection.8
Lacerations are wounds that are caused by shear forces that result
in a tearing of the tissue. They are subclassified as avulsion, shear,
or tension lacerations. Avulsion lacerations are injuries where there
is sharp trauma at an angle that removes the epidermal and possibly
also the dermal layer of skin. The injury creates a skin flap. Shear
lacerations are produced by a sharp force, usually perpendicular to
the skin surface, that results in a tidy or clean wound. These wounds
are usually caused by knives, glass, or sharp metal objects. There is
little tissue damage, and this type of wound is not prone to infection.
Tension or tensile lacerations are injuries with jagged or contused
edges that are created by a compressive force. These wounds pose a
greater risk for infection than shear lacerations.8
Punctures result in a wound that is deeper than it is wide. The
skin opening is small and the depth of the wound is often unknown.
Such wounds are made by discrete and thin objects, and they carry a
high risk for infection. Irrigation is mandatory for puncture wounds;
however, the pressure must not be so high as to drive contaminants

deeper into the wound.

The wound may also be clinically classified based upon an estimate of microbial contamination and the subsequent risk of infection. Clean wounds are those that occur under aseptic technique.
These are usually surgical incisions that are elective in nature and
preceded by a thorough skin cleansing and decontamination process. Clean-contaminated wounds are those associated with the
usual and normal flora of the region. There is no contamination
from foreign bodies or pus. Contaminated wounds are those that
are traumatic (e.g., lacerations, open fractures), less than 12 hours
old, or associated with a break in aseptic technique. Most wounds
seen in the Emergency Department are of the contaminated type.
They may be associated with the introduction of “dirt” or foreign
bodies into the wound. Dirty wounds are those that are heavily
contaminated (e.g., soil or feces), occur through infected tissue,
are over 12 hours old, are associated with retained foreign bodies,
or associated with devitalized tissue.

TIME OF INJURY
This is probably the most pertinent factor of the history. After
3 to 6 hours, the bacterial count in a wound increases dramatically. Few studies have been conducted to determine the maximal
time in which lacerations can be closed without resulting in infectious complications. One study performed in an underdeveloped
country indicated that wounds might be closed up to 18 hours
postinjury.9 Lacerations of the face and scalp that are reasonably
clean may be closed primarily up to 12 to 24 (or even 48) hours
postinjury with little risk of infection because of the excellent circulation in these areas. Other lacerations may generally be closed
primarily if they are less than 6 to 12 hours old provided that they
are not heavily contaminated or located in high-risk areas (i.e.,
hand or foot). The infection rate rises rapidly after 12 hours.

WOUND ASSESSMENT
A complete examination and documentation of the laceration is

necessary. This includes noting the location and depth of the laceration, the presence of any gross contamination, the presence of an
obvious foreign body, and any associated injuries.
Assessment of soft tissue wounds involves an examination of
the surrounding tendons as well as the vascular and neurologic
structures; bony injuries and foreign bodies should also be sought.
Emergency Physicians must possess a working knowledge of functional anatomy, particularly of the face and distal upper extremity.
Hemostasis can be achieved by direct pressure with a gauze
sponge or gloved finger for simple lacerations. Suturing the wound
best controls bleeding of the scalp. Extremity wounds, particularly of the wrist and hand, should have a pneumatic tourniquet
applied after the extremity is elevated for 1 minute to promote
venous drainage. Inflate the cuff above the patient’s systolic blood
pressure for 20 to 30 minutes at a time. A blood pressure cuff may
be substituted if a pneumatic tourniquet is not available. For more
severe bleeding, there are several commercial tourniquets available,
as well as new hemostatic agents such as Quick Clot.37–39 Vascular


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structures (with the exception of small arterioles, small venules,
and vessels within muscles) should not be clamped and may
require special techniques for hemostasis.
Wounds may cross tissue planes, opening them and creating
potential pockets or dead spaces. Elimination of the dead space
has been advocated in the past to decrease the probability of this
area becoming a nidus for infection. This once traditional practice
of obliteration of dead space to avoid infection of a nonvascularized space or to prevent hematoma formation is now considered
controversial. Studies in animal models have found the incidence

of infected wounds to be consistently proportional to the number of suture layers.10,11 Leaving dead space open resulted in lower
rates of infection than obliterating it with sutures.10,11 Studies in
1994 and 1996 concluded that buried absorbable sutures increase
the infection rate and the degree of inflammation in contaminated
wounds and do not significantly increase the degree of inflammation in noncontaminated wounds.12 Sutures placed in fat contribute
no strength to the repair and fail to prevent hematoma formation
and infection. Deep absorbable sutures may be placed to repair
the periosteum, muscles, or fascia or to minimize tension on skin
sutures. Use only enough subcutaneous sutures to restore anatomic and functional integrity. In most wounds, however, leaving
potential space may be preferable to attempting to obliterate it.
It is important to explore the deep structures through a full range
of motion in order to detect partial tendon lacerations or joint capsule disruption. Tendons can be evaluated by inspection, but individual muscles must also be tested for full range of motion and
full strength.
A distal neurologic and vascular examination should be performed on extremity injuries. Capillary refill should be checked distally and take less than 2 seconds. Neurologic assessment involves
checking distal muscle strength and sensation. Check two-point
discrimination prior to the administration of anesthesia for
hand and finger lacerations. Two-point discrimination at 5 mm on
the radial and ulnar aspects of the finger pads is the most efficient
method of assessing median and ulnar nerve function. Two-point
discrimination should be less than 1 cm at the fingertips. A crush
injury may be associated with decreased two-point discrimination
and may take several months for recovery. Numbness may also be
the first sign of a developing compartment syndrome. Nerve lacerations can be repaired immediately or the wound can be loosely
approximated and repair of the lacerated nerve delayed.
Obvious as well as questionable fractures should receive a radiograph of the area. Bone injuries require checking the overlying skin
to exclude an open fracture. An open fracture is an indication for
surgical debridement and repair except in the case of a distal phalanx fracture, which can be treated with copious irrigation, oral antibiotics, and detailed discharge instructions.

WOUND FOREIGN BODIES
Failure to identify foreign bodies in wounds may lead to complications

such as an increased risk of infection, delayed wound healing, and
loss of function.36 Foreign bodies and foreign matter greatly enhance
the infectivity of a given bacterial inoculum.13 Retained foreign bodies are a common complication of simple wound repair. Perform a
thorough inspection to attempt to diagnose the presence of a foreign body. Missed foreign bodies are the second leading cause (14%)
of lawsuits brought against Emergency Physicians.14 Some foreign
bodies cause an inflammatory reaction (e.g., wood, thorns, splinters,
cloth, teeth, and rubber from shoes or foam insoles), while others do
not (e.g., metal, glass, most plastics, and pencil graphite).
Wound exploration, irrigation, and radiography may be
needed when the clinical setting suggests a possible foreign body.
Spread the tissue during exploration. Do not cut tissue and risk

neurovascular injury. Puncture wounds have not been proven to
benefit by coring or probing to determine the depth of the wound.
Imaging may be required to detect retained foreign bodies. Retained
wood, thorns, and plastic are often detectable only by wound exploration and may not be visible on plain radiographs. Radiographs
will identify retained metallic fragments and more than 90% of glass
foreign bodies if the glass does not have a low lead content and the
fragments are at least 2 mm long.15,16 Wound markers can be used
during radiography. Radiographs obtained in two planes can help
localize the object for recovery. Glass may penetrate at an angle and
be buried deeper than it appears. The use of ultrasound is controversial because of its lack of specificity, lack of sensitivity, and operator dependency.
Foreign bodies that do not cause an inflammatory reaction are
often not removed from lacerations. This is especially true if there
are multiple fragments or if excessive tissue disruption will result
with attempted removal. The patient should be made aware of any
retained foreign bodies at the time of discharge, their benign
presence, why removal was not attempted, the possibility of later
infection, and the fact that they may eventually self-extrude. This
must also be documented in the medical record. If the wound is

in a complex area, such as the palm, it may be necessary to gain
consultation for immediate or delayed removal. The wound can be
approximated loosely and immobilized for comfort and to avoid
further tissue disruption, antibiotics prescribed, and arrangements
made for appropriate out-patient follow-up in 24 to 48 hours.
Soils have varied levels of contamination potential. Sandy soils
present a low risk of wound contamination. Clay-containing soils
are pyogenic because they impair host defense mechanisms and
promote inflammation. Organic soils contain Clostridium tetani
and a more concentrated bacterial inocula. Soil contaminants, when
present, can be removed by copious irrigation. These contaminated
wounds should be left open and allowed to heal by secondary or
tertiary intention.

HIGH-RISK WOUNDS
Many wounds require special consideration in deciding upon the
method of closure, the type of suture to use, and the use of antibiotic
prophylaxis. These include wounds contaminated by saliva, feces,
vaginal secretions, soil, and organic material. Wounds in immunocompromised patients or patients taking immunosuppressive
drugs may require antibiotics and longer times for the sutures to
remain before removal. Hand wounds, including bite wounds, and
foot wounds require special care. Wounds greater than 6 to 12 hours
old, other than wounds on the face, may require delayed closure.
Puncture wounds may require radiographs, incision and exploration, and antibiotic prophylaxis. Wounds accompanied by excessive
tissue damage and devitalization or crush injuries are prone to infection. Wounds with retained foreign bodies may require radiographs,
exploration, and removal. Major tissue defects may be closed with
advanced wound closure techniques. Wounds overlying sites of
active infection require antibiotics and delayed closure. These topics
are covered further on in this chapter and in other chapters of this
book (see Chapters 95 through 98 for details).

SKIN AND WOUND PREPARATION
ANESTHESIA
Wounds must be anesthetized with either local or regional techniques prior to cleansing and repair. Local anesthesia distorts
wound edges; therefore regional nerve blocks should be used where
appropriate (e.g., the hand, face, ear, nasal cartilage, palm, sole).
Refer to Chapters 123 through 129 for a complete discussion of local


CHAPTER 92: General Principles of Wound Management

anesthetic agents, regional anesthesia, topical anesthesia, nitrous
oxide anesthesia, and procedural sedation.
Lidocaine (Xylocaine) in a dose not to exceed 4.5 mg/kg is an
effective and standard local anesthetic agent. Lidocaine anesthesia
lasts approximately 60 to 90 minutes. If a longer period of anesthesia is required, bupivacaine may be used. It provides approximately
120 to 180 minutes of anesthesia. The addition of a 1:100,000 dilution of epinephrine to lidocaine or bupivacaine will prolong the
duration of anesthesia, promote hemostasis, allow a larger dose to
be used, and reduce systemic absorption of locally infiltrated local
anesthetic solution. Epinephrine is a potent vasoconstrictor and
should not be used near end organs such as the fingers or toes. It
may decrease blood flow and induce ischemia. Epinephrine should
also be avoided near the tip of the nose, the ear, and the penis.
Animal model studies have consistently shown that epinephrine
increases the incidence of infection in contaminated wounds. This
may be due to vasospasm-induced local ischemia. Epinephrine
should not be used to enhance local anesthesia in contaminated
wounds. Consider the use of regional anesthesia or procedural sedation in these patients.
The pain of local anesthetic injection can be reduced. The use
of a 27 or 30 gauge needle, slower and deeper infiltration (into the

dermis), warming the local anesthetic solution, and the addition of
bicarbonate to lidocaine (9 mL lidocaine to 1 mL of bicarbonate)
may decrease the pain of anesthetic injection.21–26 Other strategies
involve anesthetizing as much tissue as possible through a single
site, starting proximally on the extremity and moving distally.
Infiltration of the local anesthetic solution through the wound edges
is less painful than through intact skin.
Most “allergic” reactions are actually vasovagal or other adverse
responses. Allergies to “caines” are attributed to what is often a vasovagal or other side effect. True allergies to local anesthetics are rare
and are generally seen only with the ester class of local anesthetics.
If an allergy to lidocaine (an amide class of local anesthetic) is suspected, the use of an ester class of local anesthetic is suggested. An
alternative is the use of cardiac lidocaine, the prefilled syringes used
in codes and cardiac arrests, which contains no preservative. It is felt
that the preservative in lidocaine is responsible for the allergic effect.
Another alternative is to use a 1% to 2% solution of diphenhydramine (Benadryl). This provides adequate but not ideal anesthesia.
The most common complication of local anesthesia infiltration is
hypotension and bradycardia as a result of a vasovagal reaction.
Topical anesthesia is an attractive alternative to injection, particularly in the management of pediatric patients with simple wounds.
Lidocaine, epinephrine, and tetracaine (LET) gel or tetracaine,
adrenaline, and cocaine (TAC) are two agents that can be used as
effective local anesthesia.27 Both of these agents contain epinephrine
and should not be used on areas involving an end artery or contaminated wounds. TAC involves expense and incorporates problems
with the use and maintenance of a controlled substance. TAC also
has the potential for toxicity, especially when applied to mucosal
surfaces. EMLA (eutectic mixture of local anesthetics) cream, also
used for local anesthesia, has been found to provide effective anesthesia for extremity lacerations. EMLA is a combination of 2.5%
lidocaine and 2.5% prilocaine suspended in an oil-in-water emulsion. Studies have found that it takes longer to obtain optimal anesthesia with EMLA than with TAC.28

613

light, anesthesia, and equipment are a must in order to avoid
inadequate debridement, a retained foreign body, or a wound
hematoma that can result in a necrotizing soft tissue infection.
Disinfecting the intact skin surrounding the wound and ridding it
of foreign bodies, debris, and particulate matter is the initial step in
wound preparation. This technique can be accomplished by scrubbing the skin with povidone iodine, chlorhexidine, or poloxamer
188 (Shur Clens) skin-prep solutions. Do not expose the wound
itself to these solutions. Povidone iodine and chlorhexidine solution are bactericidal and work as it dries. Its toxicity to wound tissue
is controversial. Shur Clens has no tissue toxicity but also has no
antibacterial activity. A wide area surrounding the wound should be
prepped with an antimicrobial agent, preferably povidone iodine or
chlorhexidine solution.

HAIR REMOVAL
Hair removal is often unnecessary prior to closing wounds, can be
embarrassing for the patient after discharge from the Emergency
Department, and may increase the risk of wound infection. Shaving
can cause minimal soft tissue trauma and wound infections.17
Eyebrows should never be shaved, as they can grow back unpredictably or not at all. Simple scalp lacerations can be exposed by
using antibiotic ointment (or lubricating gel) to move the hair away
from the wound margins prior to placing sutures.

WOUND IRRIGATION
Wound cleansing and preparation have been proven to be the
foundations of proper wound management and the prevention
of wound infections. Irrigation removes contaminants, reduces
infection, and improves visualization. There are two concerns
regarding wound irrigation: the pressure required for adequate
cleansing of the wound and the means to irrigate the wound safely
while protecting the healthcare worker from the threat of human

immunodeficiency virus and hepatitis B (by contamination of their
own skin surfaces, mucosal surfaces [eyes, nose, or mouth], or
minor open skin wounds).
Irrigation pressures of 5 to 8 pounds per square inch (psi) are
felt to be adequate to cleanse a wound that is not heavily contaminated. This surface pressure can be generated by the combination
of a 35 mL syringe and a 19 gauge angiocatheter held 2 cm from
the wound surface.18,40–42 Unfortunately, this process can be quite
messy (Figure 92-1). High-pressure irrigation, which generates

SKIN CLEANSING
Meticulous preparation of the skin surrounding the wound and
the actual wound, irrigation, and wound debridement are tantamount to good wound healing. The goal is to remove bacteria,
foreign matter, and tissue debris. Wounds should be adequately
anesthetized prior to cleansing and/or local exploration. Adequate

FIGURE 92-1. Wound irrigation with an angiocatheter on a syringe. This process
is quite messy and can result in an occupational exposure. (Photo courtesy of
Zerowet Incorporated.)


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SECTION 7: Skin and Soft Tissue Procedures

peak pressures of 25 to 40 psi, has been a controversial issue in the
Emergency Medicine literature. The theory is that high pressures
may cause tissue disruption and increase infection rates. Highpressure irrigation should be reserved for highly contaminated
wounds. High-pressure irrigation may drive contaminants deeper
into puncture wounds and should be avoided.
Though there are a variety of irrigation fluids, the optimal type

is unknown. Normal saline is the most commonly used irrigant.
The volume of irrigation fluid to be used has not been well established. The use of 100 to 300 mL has been suggested in the literature.
Heavily contaminated wounds require larger amounts of irrigant.
Anecdotal recommendations suggest using 50 mL/cm for clean
wounds and 100 mL/cm for dirty wounds. Heavily contaminated
wounds may have to be scrubbed (after adequate anesthesia) with
fine-mesh gauze or a micropore sponge using a 1% solution of povidone iodine or poloxamer 188. Tap water can be used for irrigation
with no increased incidence of infection, especially when a large
volume of irrigant is required.43–47 Soaking of wounds is discouraged as a poor substitute for the preparation of contaminated or
clean wounds. Do not soak wounds in any fluid. Soaking does not
reduce bacterial contamination or decrease infection rates. It may
actually increase infection rates. Do not use undiluted povidoneiodine, hydrogen peroxide, or detergents in the wound as they
cause tissue toxicity.48
Numerous commercially available devices are available to irrigate
a wound (Figure 92-2). The Combiport (Moog Medical Devices,
Salt Lake City, UT) is a wound irrigation device that inserts directly
into the port of an intravenous fluid bag (Figure 92-2A). Squeeze

the bag of saline and direct the stream of fluid through the device
and into the wound. Wound Wash Saline (Church & Dwight, East
Princeton, NJ) is sterile normal saline within a pressurized can
(Figure 92-2B). Direct the tip of the can toward the wound, press
the button, and direct the saline stream into the wound. This is also
available at retail stores for patients to use at home for wound care.
The company offers a convenient chart that uses wound depth and
base characteristics to determine how much saline to use to irrigate
the wound. The can controls the pressure (6 to 13 psi), so that tissue is not devitalized during the irrigation. Unfortunately, using this
method is quite messy as the saline and wound materials (e.g., tissue
fluid, blood, and debris) splash all over.
The Emergency Physician should use barrier protection to shield

their face, eyes, skin, and submucosal surfaces during the irrigation process. There are several barrier devices on the market that
decrease the splatter of irrigation fluid19 (Figure 92-2). Some of these
devices are preattached to a wound irrigation device. Others can be
attached to a wound irrigation device. The Zerowet Supershield
(Zerowet Inc., Palos Verdes Peninsula, CA) is a dome-shaped
device that attaches to a syringe (Figure 92-2C). The Combiguard
Irrigation Splash Guard (Moog Medical Devices, Salt Lake City, UT)
is similar in function to the Zerowet Splashield and has a slightly
different shape. The Combiguard can attach to a syringe or the
Combiport Wound Irrigation Device (Figure 92-2D). The Igloo
Wound Irrigation System (Bionix Medical Technologies, Toledo,
OH) is a similar device that provides a multiport shower effect to
deliver the irrigation solution (Figure 92-2E). The Irrijet (Cooper
Surgical, Trumbull, CT) is a spring-loaded, self-refilling system that

A

FIGURE 92-2. Commercially available wound irrigation devices. A. The Combiport
Wound Irrigation Device (Moog Medical Devices, Salt Lake City, UT). B. Wound
Wash Saline (Church & Dwight, East Princeton, NJ).

B


CHAPTER 92: General Principles of Wound Management

D

C

F

E

FIGURE 92-2. (continued ) C. The Zerowet Supershield (Zerowet Inc., Palos
Verdes Peninsula, CA). D. The Combiguard (Moog Medical Devices, Salt Lake
City, UT) attaches to the Combiport or a syringe. E. The Igloo Wound Irrigation
System (Photo courtesy of Bionix Medical Technologies, Toledo, OH). F. The Irrijet
(Cooper Surgical, Trumbull, CT). G. The Canyons Wound Irrigation System (Wolf
Tory Medical Inc., Salt Lake City, UT).

G

615


616

SECTION 7: Skin and Soft Tissue Procedures

H

I

J

FIGURE 92-2. (continued ) H. The Squirt Wound Irrigation Kit (Merit Medical
Systems Inc., South Jordan, UT). I. The Klenzalac (Zerowet Inc., Palos Verdes
Peninsula, CA). J. The Splashcap (Splash Medical Devices, Atlanta, GA). K. The
Irrisept (Photo courtesy of Irrisept, Gainesville, FL).

K


CHAPTER 92: General Principles of Wound Management

617

is operated with one hand (Figure 92-2F). A Splashield or Splash
Guard can be attached to the Irrijet. The Canyons Wound Irrigation
System (Wolfe Tory Medical Inc., Salt Lake City, UT) is a similar
device with the exception of using the built-in Zerowet Splashield
(Figure 92-2G). The Squirt Wound Irrigation Kit (Merit Medical
Systems Inc., South Jordan, UT) is a manually operated system that
may be used alone or attached to the Splashield, Combiguard, or an
angiocatheter (Figure 92-2H). The Klenzalac (Zerowet Inc., Palos
Verdes Peninsula, CA) is a similar device with the exception of
using the built-in Zerowet Splashield (Figure 92-2I). The Splashcap
(Splash Medical Devices, Atlanta, GA) attaches to a bottle of sterile saline (Figure 92-2J). The Irrisept (Irrisept, Gainesville, FL)
attaches to a proprietary bottle containing a saline and chlorhexidine mixture (Figure 92-2K).

WOUND DEBRIDEMENT
Debridement creates straight and clean wound edges that are easier
to repair by removing tissue that is devitalized, contaminated by
bacteria, or contaminated by foreign matter and may impair the
ability of the tissue to resist infection. Successful wound closure may
require the transformation of a ragged laceration, the removal of
devitalized tissue, or the removal of contaminated tissue in order
to convert a traumatic wound into a surgical wound. Devitalized
and necrotic tissue must be removed in order to remove a nidus for

bacterial growth and wound infection.20
Close approximation of the wound requires that debridement
of jagged edges not be too vigorous in order to avoid widening
the scar and making it difficult to close. Wounds of the face or
areas that are devoid of redundant tissue require conservative
debridement. Debridement to simplify wound closure is not
always the answer for a superior cosmetic result in the repair of
irregular wound edges. The meticulous repair of complex wound
edges can often provide a superior cosmetic result.
Debridement can be accomplished mechanically, hydrodynamically, or with a combination of both methods. Tissue must be
removed mechanically with a #11 or #15 scalpel blade or a scissors
(Figure 92-3). Superficial debris and contaminants can be removed
with a pulsatile stream of normal saline solution during the irrigation process. Debridement must be performed using aseptic technique. Scrubbing is not a substitute for debridement of heavily

FIGURE 92-3. Wound debridement. Removal of the wound edges with a scissors
(or a scalpel).

FIGURE 92-4. Wound excision. Removal of an ellipse of tissue that contains the
wound results in smooth, clean edges that can be approximated.

contaminated tissue. Wound edges should be handled delicately
or gingerly in order to avoid further soft tissue damage and devitalization of injured tissue.

WOUND EXCISION
The entire wound may be excised in areas of excess tissue or tissue
laxity if no blood vessels, nerves, tendons, or joints lie within or at
the base of the wound (Figure 92-4). The excision of a wound creates smooth, clean edges that may be approximated with sutures.
This is especially useful in wounds that are heavily contaminated.
Most wounds are excised with an elliptical incision (Figure 92-4).
Other types of wound excision are discussed in Chapters 95 and 96.

Carefully plan the excision before removing any tissue. Mark
the edges of the proposed incision with a marking pen. The long
axis of the ellipse should be two-and-a-half to four times as long
as the greatest width of the ellipse. Removal of too much tissue will
produce a large defect that may not be possible to close primarily.
Remove the tissue using aseptic technique, preventing any contamination of the new wound edges.

WOUND UNDERMINING
The undermining of tissue creates a “flap” that involves the separation of the skin and superficial subcutaneous tissue from the
deeper subcutaneous tissue and fascia (Figure 92-5). The process
of undermining tissue minimizes skin tension, allows for eversion
of the approximated skin edges, and relieves the extrinsic tension from sutures. Undermining is performed when the wound
cannot be closed due to a tissue defect or if a wound is under
tension. This procedure requires the Emergency Physician to be
familiar with the local anatomy so that no blood vessels, nerves,
or tendons are injured in the process. Do not undermine contaminated wounds. Undermining large areas can separate the
skin from its underlying blood supply and result in a diminished
blood flow that predisposes the area to infection and necrosis.
Undermining may be useful on the forehead, scalp, arm, forearm,
thigh, calf, and torso. Never undermine wounds on the palms,
soles, and face.
Undermine tissue at the dermal-epidermal junction or within the
subcutaneous adipose tissue. The amount of undermining necessary to close a laceration is approximately double the width of the
gap of the laceration at its widest point. A 1 cm wide laceration
should be undermined for 1 cm on both sides of the wound, including the ends (Figure 92-5). The use of a Mayo scissors versus a #15
scalpel blade to undermine tissue is based on physician experience


618

SECTION 7: Skin and Soft Tissue Procedures

FIGURE 92-5. Wound undermining. A. Sharp undermining with
a #15 scalpel blade. B. Blunt undermining with a Mayo scissors.

and preference. A Mayo scissors is recommended as it may cause
less secondary injury, especially in experienced hands.

EMERGENCY DEPARTMENT VERSUS
OPERATING ROOM MANAGEMENT
OF WOUNDS
Laceration repair may sometimes have to be performed in the operating room. Indications for operating room repair of lacerations
include those associated with open fractures, major or complex
wounds involving devitalized tissue, heavily contaminated wounds,
wounds with associated injuries (e.g., visceral, neurovascular, fracture, and tendon), perineal wounds, large or complicated soft tissue
injuries, compartment syndromes, wounds with extensive amounts
of necrotic or ischemic tissue, the total local anesthetic solution
required would exceed toxic tissue levels, and high-pressure injection injuries.

ANTIBIOTIC PROPHYLAXIS
Despite the best wound care and management, the rate of infection
has been determined to be approximately 1% to 12%. Not all wounds
result in infection. Most uncomplicated wounds heal without the
need for antibiotics. Wounds associated with an increased risk for
infection are those of the extremities (especially the lower), complex
wounds, or wounds over 3 to 5 cm in length. The use of antibiotics
for traumatic wounds is controversial. Prophylactic antibiotics are
not indicated for uncomplicated minor wounds with a low chance
of becoming infected. It has not been proven that oral antibiotic
administration following injury actually reduces the probability of

infection. However, the use of topical antibiotics can decrease the
rate of wound infection.34 Useful preparations include bacitracin,
triple antibiotic ointment, or silver sulfadiazine.
It is necessary to identify those patients who may benefit from
early antibiotics. Antibiotic therapy should be considered in the
following situations: where wounds are heavily contaminated or
associated with major soft tissue injury; open fractures, intraoral
lacerations, wounds associated with active infection; when there is
a delay in care that results in a prolonged time from debridement or
treatment (>3 hours); when the patient is immunocompromised or
has cardiac valvular disease; when there are bites to the hand or face,
deep puncture wounds, or lacerations to lymphedematous tissue; or
when the patient has prosthetic joints (Table 92-3).

SUTURES
SUTURE TYPES
Proper size suture material can be summarized as the smallest
suture needed to approximate the edges of a wound. This will reduce

tissue damage caused by the suture, and the resulting scar will be
minimized. The tensile strength of the suture should never exceed
the tensile strength of the tissue, or it can pull through and damage
the tissue. The sutures should be at least as strong as the normal tissue through which they are being placed.
The size of the suture material is related to the diameter of the
suture. As the number of 0s in the suture size increases, the diameter
of the strand decreases. For example, size 5-0, or 00000, is smaller in
diameter than size 4-0, or 0000. The smaller the size, the less tensile
strength the suture will have.
Suture description entails numerous characteristics. Sutures
can be classified into two major groups based upon the number

of strands of which they are composed. Monofilament sutures
are made of a single strand of material. They encounter less resistance passing through tissue and resist harboring organisms that
may cause suture-line infections. Multifilament sutures consist of
several filaments, or strands, that are twisted or braided together.
This affords greater tensile strength, pliability, and flexibility.
Unfortunately, bacteria can migrate between the filaments and into
the wound.
Another classification is based on the ability of the body to break
down and absorb the suture material. Absorbable sutures are digested
by body enzymes or hydrolyzed in body tissue. Nonabsorbable
sutures are not digested by body enzymes or hydrolyzed.
Absorbable suture can be made of natural or synthetic material. Natural absorbable suture is classified as surgical gut (plain or
chromic). Plain surgical gut is composed of collagen from bovine
or sheep intestine. It is rapidly absorbed, maintaining its tensile

TABLE 92-3 Antibiotic Prophylaxis for High-Risk Wounds35
Situation
Antibiotic of choice
Days of treatment
Open fractures
First Generation Cephalosporin
1–3
Add an aminoglycoside for more
extensive injuries
Intraoral injuries
Penicillin VK or Clindamycin
5
Human bites
First dose: parenteral ampicillin
3–5

sulbactam or Ertapenem, then
Augmentin
Or
Clindamycin plus fluoroquinolone
(Bactrim in children)
Or
Augmentin
Dog/cat bites
First dose: parenteral ampicillin
3–5
sulbactam or carbapenem or
clindamycin, then clindamycin
plus fluoroquinolone
Or
Augmentin


CHAPTER 92: General Principles of Wound Management

strength for only 7 to 10 days, and is completely absorbed within
70 days. Chromic gut is treated with a chromium salt solution to
resist body enzymes. It retains its tensile strength for 10 to 14 days
and is absorbed over 90 days.
Synthetic absorbable sutures include polyglactin 910 (Vicryl,
Ethicon) and polyglycolic acid (Dexon). They were developed
because of the tissue reaction, suture antigenicity, and unpredictable
rates of absorption of natural absorbable sutures. These sutures are
braided synthetic materials that retain 50% of their initial strength
at 4 weeks. The synthetic absorbable sutures retain their tensile
strength long enough to ensure the security of the subcutaneous

layers after the removal of percutaneous sutures.
Nonabsorbable sutures are made of silk, nylon, polypropylene,
cotton, linen, or metal. They can be monofilament or multifilament in construction. Nylon is the most commonly used suture in
the Emergency Department. It is used to approximate lacerations
at the skin surface. Silk may occasionally be used in the mouth. It
causes significant tissue reactions that result in inflammation and
granuloma formation as the body “fights off ” this natural fiber. The
other types of nonabsorbable sutures are generally not utilized in
the Emergency Department.
Several factors must be considered in choosing suture material.
Choose sutures that match the healing properties of the tissues.
Approximate slow-healing tissues (e.g., fascia and tendons) with
nonabsorbable sutures or a long-lasting absorbable suture. Foreign
bodies in potentially contaminated tissues may result in an infection. Multifilament sutures can act as a foreign body and may convert a contaminated wound into an infected one. Multifilament
sutures should generally be avoided. Use monofilament sutures or
absorbable sutures that resist harboring infection. Use the smallest
inert monofilament suture materials (such as nylon or polypropylene), avoid using skin sutures alone (use subcuticular closure whenever possible), and use sterile skin closure strips for apposition when
possible. Use the smallest possible size of the chosen suture type
that is capable of closing the wound to help minimize scarring.

NEEDLES
Needles are generally of two types, tapered and cutting
(Figure 92-6). Cutting needles have sharp ends and sharp edges
that act as a cutting instrument (Figure 92-6A). The cutting needle
is commonly used for tougher tissues such as subcutaneous, intradermal, and cutaneous (skin) closure. In addition to the two cutting

A

C

619

edges, conventional cutting needles have a third cutting edge on
the inside concave curvature of the needle. This needle type may
be prone to “cutout” of tissue because the inside cutting edge cuts
toward the edges of the incision or wound.
Reverse cutting needles are as sharp as the conventional cutting
needle except that the third cutting edge is located on the outer
convex curvature of the needle (Figure 92-6B). Reverse cutting
needles have more strength than similar-sized conventional cutting needles. The danger of tissue “cutout” is greatly reduced. The
hole left by the needle leaves a wide wall of tissue against which the
suture is to be tied.
Taper point needles have a pointed end (Figure 92-6C). The rest
of the needle is a smooth, rounded tube with no cutting edges. This
type of needle is commonly used in surgery to close tissues with
minimal trauma. It is used for all tissues except skin.
Two other types of needles are often available but not used in the
Emergency Department. The blunt point needle has a smooth tip
and tapered body (Figure 92-6D). It is used for suturing friable tissue and blunt dissection. The taper cut needle has a cutting tip and
a tapered body (Figure 92-6E). It is a combination of the tapered
point and cutting needle. It is used to place sutures through tough
tissues. Numerous other needles are available, as are modifications
of the five basic needle types. These needles are used by Surgeons
for specialized tissues.
Always keep some general principles in mind when suturing.
Needles should be pulled through tissue using a needle driver
and never a hemostat. A hemostat or other clamp can damage the
needle. Avoid injury to yourself and others. Keep all open needles in a place so that they will not injure you or your assistant.
Account for and discard all suture needles in a “sharps” container.
Following these two steps will dramatically decrease the chance for

a needle-stick injury.

NEEDLE DRIVERS AND HANDLING SUTURES
Always use a needle driver when suturing. The use of a hemostat or
other type of “clamp” can damage the needle and cause it to bend or
break in the tissue. Needle drivers are generally made of steel with a
jaw designed to hold the needle securely without damaging it. They
come in numerous sizes and shapes. Choose a needle driver that is
an appropriate size for the needle that is to be grasped. A 4.5 to 6 in.
long needle driver is appropriate for Emergency Department use.
Grasp and remove a clean needle from its package with your hands,

B

D

E

FIGURE 92-6. Common types of suture needles. A. The cutting needle. B. The reverse cutting needle. C. The taper point
needle. D. The blunt point needle. E. The taper cut needle.


620

SECTION 7: Skin and Soft Tissue Procedures

FIGURE 92-8. Examples of snag-free needle drivers. From left to right: The
Centurion SnagFree (Centurion Healthcare Products, Howell, MI), the SutureCut
needle driver (SutureCut LLC, Lexington, KY), and the Olsen-Hegar needle driver
(Henry Schein Inc., Port Washington, NY).

FIGURE 92-7. Using a needle driver. A. Grasp the proximal one-third to one-half
of the needle. B. Always use the tips of the jaws to grasp the needle. C. Drive the
needle through the tissue following the natural curve of the needle. D. Grasp
the distal needle proximal to the cutting edges. E. Correct method to pass a needle
driver armed with a needle.

forceps, or a needle driver. Securely grasp the proximal one-third to
one-half of the needle with the needle driver (Figure 92-7A). Do
not grasp the distal one-third of the needle. This can damage its
cutting surfaces. Always use the tips of the needle driver to grasp
the needle (Figure 92-7B). Grasping a needle with the base of the
jaws may damage the needle.
Use the needle driver when pushing the needle through the tissue
to place a suture (Figure 92-7C). Apply the force in a direction following the curve of the needle. Do not twist or force the needle
to push the point through the tissue and out the other side. Use a
larger needle if the first one is too short or too small. Do not use a
needle that has become dull and difficult to pass through the tissue. Obtain a new needle and continue the procedure. Grasp the
distal tip of the needle with a needle driver when it emerges from
the tissues (Figure 92-7D). Always grasp the needle proximal to
its distal third to prevent damage to the cutting edges.
Always use caution when handing a needle driver armed with
a needle to another person. Grasp the needle driver between the
thumb, index, and middle fingers (Figure 92-7E). Hand the base of
the needle driver to another person. Do not blindly pass the needle
driver. Do not pass the needle driver over a third party without
their knowledge of the transfer. Never grasp the distal end of an
armed needle driver.
Typical needle drivers contained within most disposable, commercially available laceration repair trays are not ideal. The suture
often snags on the jaws or hinge when performing an instrument tie.

Some needle drivers are designed to be snag-free (Figure 92-8). Two
of these, the Centurion SnagFree (Centurion Healthcare Products,
Howell, MI) and the SutureCut (SutureCut LLC, Lexington, KY)
needle drivers, are available both as individual disposable instruments and in disposable laceration repair trays.
Suturing lacerations can take a significant amount of time. Much
of this time is spent tying knots or switching between instruments
(i.e., the needle driver and scissors). Two needle drivers are designed
to also cut suture. This decreases the total time required to repair
a laceration as well as avoiding the constant switching between
instruments. The SutureCut (SutureCut LLC, Lexington, KY) and
the Olsen-Hagar (Henry Schein Inc., Port Washington, NY) needle
drivers cut the suture in their specially designed joint located at the
base of the jaws.
We are all not fortunate to have suture-cutting needle drivers in our laceration repair trays. A needle driver and scissors can
be simultaneously held in the same hand to improve efficiency
(Figure 92-9). While awkward at first, this technique is easy to
learn. Grasp a scissors with the tip pointing ulnarly (Figure 92-9A).
Insert your middle finger through the adjacent ring on the handle.
Grasp a needle driver in the same hand with the tip pointing radially (Figure 92-9A). Insert your thumb and ring finger through the
rings on the handle of the needle driver. Grasp a suture needle with
the needle driver. Place a stitch and tie it. Remove your thumb from
the ring of the needle driver and place it in the open ring of the scissors. Use the thumb to open and close the scissors. Cut off the excess
suture (Figure 92-9B). Place your thumb back into the ring of the
needle driver and place the next stitch. Repeat this process until the
laceration is closed.

WOUND CLOSURE
The goal of wound closure is approximation of the skin under
minimal tension while achieving eversion of the wound edges

(Chapter 93). Wound eversion slightly raises the wound edges
to keep the epidermal cells from migrating into the dermal layers, therefore leaving a flat scar (Figure 92-10). Sutures should
be placed closely enough to approximate wound edges, but not so
tight as to cause tissue necrosis. The time from the injury to the


CHAPTER 92: General Principles of Wound Management

A

621

B

FIGURE 92-9. A one-handed method to simultaneously hold a needle driver and scissors. A. Placing a stitch. B. Cutting the suture.

presentation and the mechanism of injury will indicate whether
the laceration mandates delayed closure instead of primary closure
and whether tetanus prophylaxis is required. With the exception of
patients who are immunocompromised or taking immunosuppressive therapy, those with high-risk wounds should be considered for
delayed closure.

SINGLE-LAYER VERSUS MULTILAYER CLOSURE
The greatest strength of the skin (and of the wound) is contained
within the dermis. The better the coaptation of the dermal edges,
the narrower the scar will be. The best results occur when the entire
depth of the dermis is accurately approximated to the entire depth
of the opposite dermis. Dermal closure is best performed with synthetic monofilament absorbable suture that requires enzymatic
degradation (e.g., Vicryl). Chromic or plain catgut suture dissolves
much more rapidly by means of hydrolysis.

Close the wound in multiple layers if the goal is cosmesis. Close
the wound with a minimal number of sutures in a single layer if the
goal is a functional result. Do not suture through fat and muscle.
Fat has no tensile strength. Sutures placed tightly in fat can cause
ischemia and necrosis in the wound and increase the risk of a

wound infection. Muscle fibers do not support sutures. Muscle is
best treated by repair of the overlying fascia and immobilization to
prevent motion and to allow coaptation of the muscle fibers.

STERILE GLOVES
It is a common practice to wear sterile gloves when repairing a laceration. The advantages of sterile gloves include a better fit, improved
tactile sensitivity, and improved dexterity. The use of sterile gloves
for laceration repair costs significantly more than using nonsterile, clean gloves from a box. Clean, nonsterile, powder-free, boxed
examination gloves can be used for uncomplicated wound repair
in the Emergency Department. No clinically important differences
in infection rates has been found when comparing sterile gloves to
clean gloves.49,50
The use of clean gloves from a box is not always ideal. Clean
gloves come in a limited number of sizes (i.e., extra small, small,
medium, large, and extra large). The fit and feel of clean gloves may
not be as comfortable for the Emergency Physician. Clean gloves
may have more manufacturing defects when compared to sterile
gloves.51 These defects can result in the loss of personnel protection
and the potential to contaminate the wound. Others have shown
clean gloves to have comparable quality to sterile gloves.52–54 A box
of clean gloves that has become wet can harbor mold.55 While the
use of clean gloves in uncomplicated wound repair is acceptable, the
decision is physician dependent.

WOUND CLOSURE PROCEDURE

FIGURE 92-10. Eversion of the wound edge signifies proper suture placement
and knot tension.

Clean any dirt and debris from the skin. Scrub the skin surrounding
the wound with an antiseptic skin cleanser (e.g., povidone iodine or
chlorhexidine). Anesthetize the wound with a 27 to 30 gauge hypodermic needle and local anesthetic solution. Irrigate the wound with
normal saline. Use a mask with a face shield to prevent exposure
to the patient’s blood and tissue fluid. Debride and undermine the
wound as necessary. Irrigate the wound again to remove exposed
debris and devitalized tissue. Repair the wound with sutures or pack
it with saline-soaked fine-mesh gauze for delayed closure. Clean the
repaired wound with normal saline and apply a dressing for comfort and protection. Consider the application of a splint for wounds
across joints or muscle lacerations.
Write a procedure note describing the sterile preparation of the
wound, the type and volume of anesthesia administered, the type
of suture(s) used in the repair, the layers repaired, the type of repair


622

SECTION 7: Skin and Soft Tissue Procedures

(interrupted vs. continuous), and how the procedure was tolerated
by the patient. Any complications should also be noted.

AFTERCARE
Wound care has become a specialty involving sophisticated research
in many areas, including dressings and the environment in which

wounds heal best. Clean the area surrounding the repaired wound
with normal saline to remove any antimicrobial agents and blood. It
has been demonstrated that optimal growth of fibroblasts in tissue
culture occurs at low partial pressures of oxygen (5 to 10 mmHg).
Epidermal cell growth is inhibited at oxygen levels higher than that
in surrounding air. It has been shown clinically that hydrocolloid
dressings are capable of maintaining low oxygen tension independent of the underlying disease process.29 The application of an
occlusive dressing has been shown to increase the rate of wound
healing by approximately 40%, as well as preventing environmental
trauma and keeping bacteria out of the wound.
Dressings, regardless of the type used, should produce a moist
but not macerated wound that is free of infection, toxic chemicals,
and foreign material while maintaining an optimum temperature
and pH. Layered dressings of nonadherent gauze, such as Xeroform,
covered with dry gauze can be used for large sutured lacerations
and abrasions. This dressing draws exudate into a layer that can be
replaced without disturbing the underlying wound. Shear wounds
or hematomas may require gauze that is fluffed and formed into a
pressure dressing. Dressings of antibiotic ointment with a standard
adhesive bandage (e.g., Band-Aid) provide adequate healing and
protection for smaller repaired lacerations. The topical application
of topical antibiotics to the suture line after wound closure may help
to protect against exogenous bacterial contamination. No studies have shown that topical antibiotic ointments have an effect on
the final outcome of a wound. Despite this, their use is still recommended because they keep the wound surface moist and their use
has not been shown to have any negative effects. The use of paper
gauze and Telfa pads is not advisable.

DISCHARGE INSTRUCTIONS
High-risk wounds such as animal and/or human bites, hand wounds,
heavily contaminated wounds, and wounds that require prophylactic antibiotic coverage should be reevaluated within 24 hours.

Patients should be made aware, orally and in writing, that up to
one in 10 persons develops a wound infection that can be treated
with an oral antibiotic. Puncture wounds are considered high-risk
injuries that can result in bone infections. Patients should immediately return to the Emergency Department or their primary physician if a wound becomes red or has a discharge, if redness or red
streaks are emanating from the wound, or if they develop a fever.
Explain briefly the progression of healing. The new scar’s appearance is usually worst at 3 to 5 weeks. Most scars remodel within 6 to
12 months. Any revision of the wound should be postponed for at
least 6 to 12 months from the time of injury.

TABLE 92-4 Suture Removal Recommendations
Location
Days
Face
3–4 (child), 3–5 (adult)
Neck
2–3 (child), 3–4 (adult)
Upper extremity
7–10
Hand
10–14
Chest
7–10
Back
10–14
Buttocks
10–14
Legs
8–10
Foot
10–14

Delayed closure
8–12
Retention sutures
14–30
Overlying joints
10–14

scars, and possibly infections. Suture removal kits are commercially
available. They typically contain a metal or plastic forceps, a scissors, and a few gauze squares. These kits are inexpensive, disposable,
and intended for single-patient use.
Sutures should be removed using aseptic and sterile techniques.
Clean the wound with saline. Apply hydrogen peroxide to remove
any dried blood and serum encrusted around the sutures. Grasp
the suture at the knot with forceps (Figure 92-11). Lift the knot
off the skin. Cut the suture as close to the skin as possible with a
scissors and where the suture enters the skin (Figure 92-11). This
will avoid drawing contaminated suture through the depth of the
wound. Sutures that are close together, small, or tight may require
a #11 scalpel blade to cut them rather than a scissors. Gently pull
the suture strand out of the tissue with the forceps and across the
wound. Pulling a suture out away from the wound may result in the
wound edges opening (dehiscing). Remove one to three sutures and
ensure that the wound edges do not dehisce. Remove the remaining sutures. Apply skin adhesive strips (e.g., Steri-strips) across the
wound to provide support.

MANAGEMENT OF PUNCTURE WOUNDS
Puncture wounds are considered to be at higher risk for infection than simple lacerations. They should be allowed to heal by
delayed intention, particularly if they penetrate into the subcutaneous tissues. Local cleansing is the initial step in management.
High-pressure irrigation, coring, and probing are generally not
recommended.

Infection is most frequently due to Staphylococcus aureus,
Staphylococcus epidermidis, or streptococcal species. Treatment
should be reserved for compromised hosts, dirty wounds, or actual
infected wounds.30 Puncture wounds of the foot are of special concern due to the risk of Pseudomonas aeruginosa infection, particularly with wounds through athletic shoes. A tender wound that
is not infected usually indicates that there may be a retained foreign body. Persistent infection from a plantar wound suggests an

SUTURE REMOVAL
The length of time that the sutures remain in place depends upon
the location of the wound, the amount of tension on the wound,
and the healing time of the involved tissue. Some general guidelines are listed in Table 92-4. Appropriate and timely removal of
sutures minimizes scarring. Full-thickness sutures can be left in
place for 2 or more weeks without risk of suture-track formation in
areas where sebaceous glands and other adnexal structures are not
present, such as the plantar and palmar surfaces. Leaving sutures in
place too long results in epithelialization of the suture tracts, larger

FIGURE 92-11. Suture removal.


CHAPTER 93: Basic Wound Closure Techniques

underlying osteomyelitis that requires radiographs and treatment
with a fluoroquinolone.31

PEDIATRIC ISSUES OF WOUND HEALING
Pediatric patients less than 15 years of age experience infection rates
of less than 1% for clean surgical wounds.7 This is less than that seen
in adults. Young children, despite the ultimate in the way of gentle
reassurance, will sometimes require sedation in order to make painful or difficult procedures possible. Safe and effective procedural
sedation for patient comfort or cooperation to facilitate or expedite

medical care is described in Chapter 129. Undermining is not useful
in most pediatric wounds as they do not usually require advancement of skin over a significant tissue defect. Scalp lacerations
account for 30% of pediatric lacerations. Scalp lacerations are well
suited for single-layer repair with staples. Cosmetic results are comparable with those of sutured repairs, with no differences in complication and infection rates. Staples are six times faster, less expensive
in cost of supplies and physician time than standard sutures, and
can be implanted rapidly and accurately, even in a moving child.

ALTERNATIVE CLOSURES
Alternative methods of wound closure include skin closure tapes,
tissue adhesives, and staples. These are mentioned briefly below. A
more complete discussion can be found in Chapters 93 and 94.

SKIN CLOSURE TAPES
Skin closure tapes are adhesive strips that are used when skin tension
and wound contamination are not concerning factors. Adhesivebacked long and narrow strips are used for approximating the edges
of lacerations (with or without staples or sutures) and for closing the
skin following many operative procedures. The most common type
is the Steri-strip. Skin closure tapes are felt to develop and increase
wound tensile strength faster than sutured wounds because uniformly orienting collagen fibers apply equal stress across the wound.
Skin closure tapes are porous, which allows for good air inflow and
the escape of water vapor from the wound during the healing process. Strips are placed perpendicular to the wound in conjunction
with an adhesive such as tincture of benzoin, taking care not to get
benzoin in the wound.

TISSUE ADHESIVES
Tissue adhesives such as the older and weaker butyl cyanoacrylates
focused on small linear lacerations. Newer and stronger medicalgrade octyl cyanoacrylate formulations have been approved by the
US Food and Drug Administration. It has been clinically proven
that there is no difference 1 year after treatment in the cosmetic outcome of wounds repaired with suture versus those closed with octyl
cyanoacrylate tissue adhesive.32

STAPLES
Staple closure is time-efficient compared to the suture repair of lacerations.33 It is primarily used for large wounds that are not on the
face, neck, hands, or feet. Stapling is especially useful for closure of
incisions in hair-bearing skin (i.e., scalp) areas as well as the trunk
and extremities. The wound edges require manual eversion with
forceps prior to placing the staples.

SUMMARY
Expert wound management consists of attention to the details surrounding the wound, gleaning important information concerning the host’s history, as well as meticulous wound preparation.

623

Aggressive attention to the presence of foreign bodies, underlying
injury to anatomic structures of significance, and the possibility of
subsequent wound infection should be kept in mind at all times.
An effort should be made to educate the patient about the possible
outcomes of wounds and lacerations and to encourage expedited
follow-up.

93

Basic Wound Closure
Techniques
Eric F. Reichman and Candace Powell

INTRODUCTION
Wound management is crucial to the practice of Emergency
Medicine. Emergency Physicians routinely care for wounds ranging
from simple lacerations to complex injuries in the trauma patient.1–6

Wound repair is always secondary to the evaluation and stabilization
of any life-threatening and limb-threatening emergencies. However,
patients are often legitimately concerned about the outcome of
wounds and lacerations. There are several basic suture principles
that will help to provide optimal wound healing and ensure a more
than acceptable cosmetic result. The previous chapter outlines the
essential principles of wound management. This chapter describes
the basic methods used to close wounds.

SUTURES
The choice of suture materials is important in wound closure.
Sutures are made of a wide variety of materials, both natural and
synthetic. Natural substances include gut (sheep and beef), cotton,
and silk. Natural substance sutures cause more tissue reactions
and scarring, which limits their use. Cotton sutures are not discussed, as they are no longer used in clinical practice. Synthetic
sutures can be made of nylon, polyethylene (Dacron), polyglactin (Vicryl), polypropylene (Surgilene, Prolene), polyglycolic
acid (Dexon), poliglecaprone (Monocryl), polydiaxanone (PDS),
polyglyconate (Maxon), and metal.6 Metal sutures are used in the
Operating Room and not in the Emergency Department as they
are difficult to handle, prone to breakage, and indicated in only
a few situations. Synthetic sutures tend to have a problem with
“memory.” That is, they tend to retain the shape of their packaging. This can make it difficult to manipulate the suture during
wound closure.
Sutures are constructed as monofilaments or polyfilaments.
Polyfilament fibers consist of multiple filaments braided together
to form one suture. They are easier to handle than monofilament
sutures, as they tend to be more pliable. Polyfilament sutures have
better knot security and therefore reduce the incidence of knot
slippage. However, they can be associated with a higher incidence
of infection than monofilament sutures. They allow bacteria to

migrate (or wick) between the strands of the suture located at the
skin surface and into the wound.
Select the smallest diameter suture that can adequately hold
the tissue edges together in order to reduce tissue damage and
scarring. The largest suture material available is size #5. The suture
sizes decrease to zero (#4, #3, #2, #1, #0) and then are followed by
#00 (2-0), #000 (3-0), and #0000 (4-0), in decreasing size. The smallest suture commonly used in the Emergency Department is 6-0 for
facial lacerations, nail bed lacerations, as well as lacerations in cosmetically sensitive areas. The tensile strength of sutures is related


624

SECTION 7: Skin and Soft Tissue Procedures

TABLE 93-1 Absorbable Suture Materials
Suture type
Source
Plain surgical gut
Beef or sheep collagen
Chromic surgical gut
Beef or sheep collagen
Monocryl
Poliglecaprone 25
Coated Vicryl
Polyglycolic 910, polyglactin 370,
and calcium stearate
Dexon
Polyglycolic acid
Vicryl Rapide
Polyglactin 910

PDS polydioxanone
Polyester polymer
Maxon

Polyglyconate

Tensile strength
Poor
Poor
20% remains by 3 weeks
65% remains at 2 weeks;
40% at 3 weeks
50% remains at 4 weeks
50% remains in 5–6 days
70% remains at 2 weeks;
50% at 4 weeks
50% remains at 7 weeks

to their size. The tensile strength of suture increases as the size
increases. For example, 4-0 is stronger than 5-0.
The other main category of suture classification is absorbable
versus nonabsorbable. In the past, absorbable sutures were primarily used to close the subcutaneous layers of a wound. More
recently, absorbable sutures have also been used for skin closure.
Nonabsorbable sutures are primarily used for skin closure.

ABSORBABLE SUTURE MATERIALS
Absorbable sutures are degraded by the body and do not require
removal. They usually do not maintain their tensile strength for longer than 60 days. Body enzymes dissolve the absorbable sutures with
the aid of an inflammatory reaction. The rate of absorption of the
sutures varies based upon the tissue where it is placed, the composition of the suture, and the size of the suture. Absorbable sutures

placed in mucous membranes absorb faster than those placed in
muscle tissue or fascia. Smaller sizes of suture dissolve faster than
larger sizes.
There are several types of absorbable sutures, both natural and
synthetic (Table 93-1). The most commonly used absorbable
sutures in the Emergency Department are plain gut, chromic gut,
polyglycolic acid (Dexon), polyglactin (Vicryl), and Vicryl Rapide.
Plain gut and chromic gut are both natural forms of absorbable
sutures. They are made from the intestines of sheep and cattle. Gut
is a tissue irritant and can cause a substantial tissue reaction while
it is being absorbed and degraded by the body. Chromic gut is plain
gut that has been soaked in chromic acid salts. This process helps to
extend the half-life of the suture and allows it to maintain its tensile
strength longer than plain gut. Chromic gut may retain its tensile
strength for 2 to 3 weeks, while plain gut retains its tensile strength
for 1 to 2 weeks. Both types of gut are packaged wet in order to keep
them from drying out and becoming too stiff.

TABLE 93-2 Nonabsorbable Suture Materials
Suture type
Source
Tensile strength
Silk (braided)
Organic protein
Gradual loss by progressive
degradation
Ethilon
Polyamide (nylon)
Progressive hydrolysis may result
in gradual loss of tensile strength

Nurolon
Polyamide (nylon)
Progressive hydrolysis may result
in gradual loss of tensile strength
Prolene
Polyamide (nylon)
Not subject to degradation
Mersilene
Polyester
No significant change occurs

Tissue reaction
Moderate
Moderate
Minimal
Minimal

Knot security
Poor
Fair
Good
Fair

Absorption
1–2 weeks
2–3 weeks
3 months
3–6 months

Minimal

Minimal
Slight

Good
Good
Poor

3–4 months
42 days
6 months

Slight

Fair

6 months

Synthetic absorbable sutures, such as Dexon and Vicryl, are
typically used more often than natural absorbable sutures in the
Emergency Department. They are degraded by the body more slowly
than natural fibers and can therefore help maintain the strength of
the wound longer. Vicryl and Dexon maintain their tensile strength
at 80 days and 120 days, respectively. They cause less reaction in the
tissues as they break down when compared to natural absorbable
sutures.
Recently, absorbable sutures have gained some popularity for use
in skin closure.7–10 Absorbable sutures have been shown to yield
equal results in their rate of dehiscence, rate of infection, and cosmesis when compared to nonabsorbable sutures.7 Absorbable sutures
have the added benefit for the patient of not having to return to have
their sutures removed. Vicryl Rapide is a newer form of Vicryl that

is especially suited for this purpose. This type of suture is rapidly
absorbed. They begin to fall off in 7 to 10 days as the wound heals.
This can be especially useful for children in whom suture removal
can be difficult, under casts, or if a patient will not be able to follow
up due to travel.

NONABSORBABLE SUTURE MATERIALS
Nonabsorbable sutures are not degraded by the body and must
be removed. They maintain their tensile strength for longer than
60 days. They are composed of monofilament or polyfilament strands
of organic, synthetic, or metal fibers (Table 93-2). Nonabsorbable
sutures generally have greater tensile strength and lower tissue reactivity than absorbable sutures. They are used in a variety of applications including skin closure. Nonabsorbable sutures can be used
within a body cavity and subcutaneously, where they will eventually
become encapsulated in connective tissue.
Nonabsorbable sutures can be classified as organic, synthetic, and
wire. Organic sutures include those made of cotton or silk. Cotton

Tissue reaction
High

Knot security
Good

Minimal

Fair

Minimal

Fair

Minimal
Minimal

Poor
Good

Ethibond

Coated polyester

No significant change occurs

Minimal

Good

Stainless steel

Stainless steel

Indefinite

Minimal

Good

Absorption
Gradual encapsulation
by connective tissue

Gradual encapsulation
by connective tissue
Gradual encapsulation
by connective tissue
Nonabsorbable
Gradual encapsulation
by connective tissue
Gradual encapsulation
by connective tissue
Nonabsorbable


CHAPTER 93: Basic Wound Closure Techniques

is the oldest of the nonabsorbable sutures. It is not discussed here
as cotton sutures are no longer used in general medical practice.
Silk is a polyfilament suture that has limited use in the practice of
Emergency Medicine. There are several advantages to silk suture
material. Its pliability makes it very easy to handle. It holds knots
better than other types of suture. However, as with all natural and/
or polyfilament sutures, it has a greater tendency to cause wound
infections. The polyfilament braids can provide a place for bacteria
to lodge. Silk suture may actually protect the bacteria from attack
by the body’s defenses if the wound becomes infected. The primary
use of silk sutures is for the repair of lip, oral cavity, and tongue
lacerations.
Synthetic nonabsorbable sutures are available in monofilament
and polyfilament forms. Commonly used synthetic sutures include
nylon, polypropylene, polybutester, and Dacron. Nylon, polypropylene, and polybutester are monofilament synthetic sutures. Dacron
is a polyfilament synthetic suture. The synthetic nonabsorbable

sutures have several advantages over the natural nonabsorbable
sutures. They are less reactive in tissues, generally stronger than the
natural sutures, and retain their tensile strength over many years.
Nylon (Ethilon, Dermalon) is the most common nonabsorbable
suture used in the Emergency Department. It is a monofilament
suture, it is inert, and it does not tend to harbor bacteria. It is primarily used for skin closure. Nylon has good tensile strength and
minimal tissue reactivity. However, nylon is difficult to handle and
difficult to tie. It requires more knots to achieve good knot security
than other types of suture. This is primarily due to the tendency of the
suture to return to its packaged shape. This tendency is also known
as “memory.” Because the knot can unravel or slip, it is important to
place at least four or five knots when using nylon suture.
Polypropylene and polybutester are less commonly used synthetic nonabsorbable sutures. Polypropylene (Prolene) is stronger
but more difficult to work with than nylon because it has greater
memory. Polybutester (Novafil) is a newer suture in this category.
It is stronger than the other monofilaments and does not have significant memory. Therefore, it is easier to work with than the other
monofilament synthetic sutures.

EQUIPMENT
•
•
•
•
•
•
•
•
•
•
•

•
•
•
•
•
•
•

Needle drivers, 4.5 and 6.0 in.
Skin hooks
Scalpel blades (#10, #11, and #15)
Scalpel handles
Iris scissors, straight 4 in. and curved 4 in.
Suture scissors, 6 in.
Forceps, toothed Adson
Metzenbaum scissors, curved 6 in.
Hemostats, straight 6 in., and curved mosquitoes
Suture material
Skin closure tapes
Benzoin solution, swabs, or spray
Gum mastic (e.g., Mastisol)
Tissue adhesive
Tissue adhesive forceps
Skin stapler
Staple remover
Gauze, 4 × 4 squares

Much of the above equipment can be purchased in singleuse, sterile, and disposable suture kits from several commercial

625

A

B
FIGURE 93-1. The equipment required for basic wound closure techniques.
A. The contents of a disposable and commercially available wound closure kit.
B. A hospital packaged kit with reusable instruments.

manufacturers (Figure 93-1A). These kits tend to be expensive and
occasionally have a limited amount of equipment. Many hospitals
package and sterilize their own wound repair kits (Figure 93-1B).
This decreases the cost, as the equipment can be repeatedly sterilized and reused. It also allows the kits to contain a wide variety of
instruments for multiple situations (e.g., minor laceration, large laceration, and plastics closure).
Needle drivers come in a variety of sizes. A 4.5 in. needle driver
can be used comfortably with most types of needles. A 6 in. needle
driver may be required if large needles are used to close a wound.
Hold the needle driver with the fingertips to provide greater flexibility. The fingers can also be placed through the finger holes, but
this is not as efficient when closing a wound. Grasp the needle
one-third of the way from the swag (distal) end with the tip of the
needle driver.
The skin must be grasped and manipulated during wound repair
to allow for proper suture placement. Forceps are most commonly
used to grasp and manipulate the skin. Smooth (nontoothed) forceps should never be used to grasp skin. They require the application of a large amount of force to grasp the tissue. This can crush
tissue very easily. An Adson forceps is the forceps of choice. It has
fine teeth that grasp tissue securely with minimal force.


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SECTION 7: Skin and Soft Tissue Procedures

TABLE 93-3 Typical Suture Choices for Each Body Site
Anatomic site
Deep-layer suture size
Deep-layer suture material
Scalp
2–0, 3–0, or 4–0
Absorbable
Eyelid
5–0, 6–0, or 7–0
Absorbable
Face
4–0 or 5–0
Absorbable
Neck
4–0 or 5–0
Absorbable
Trunk
3–0 or 4–0
Absorbable
Extremities
3–0 or 4–0
Absorbable
Hands and feet
Not advisable
Not applicable
Sole of foot
3–0 or 4–0
Absorbable

A skin hook is a sharp, pointed instrument that is inserted into
the wound edge and grasps the tissue from the undersurface. It produces a small puncture wound in the subcutaneous tissues and does
not penetrate the skin surface. Skin hooks are preferable to forceps,
as they do not crush tissues. A skin hook is awkward to use at first.
With proper instruction and experience, the Emergency Physician
will most certainly prefer a skin hook to forceps.
Several types of scissors are required for proper wound closure.
Iris scissors have sharp, delicate tips for making precise cuts in tissue. They should not be used to cut suture material, as this rapidly
dulls and nicks the blades. Suture scissors have one blunt tip and one
pointed tip. Both blades of the suture scissors are sharp. Suture scissors are used to cut adhesive tape, gauze, rubber drains, and suture
material. Metzenbaum scissors should be used to debride heavy tissue, bluntly dissect tissue, and undermine tissue.
Hemostats are used to clamp small vessels that are bleeding,
to explore a wound, and to grasp fascia. Hemostats are available
in a variety of sizes and styles. A straight 6 in. hemostat is used
for most purposes during wound repair. A curved 5 in. mosquito
hemostat can be used for small wounds or delicate tissues. Do not
use a hemostat to grasp or drive the suture needle. The suture
needle can bend, rotate, and break as it enters tissue if driven by a
hemostat.
Three different scalpel blades should be available when a wound
is being repaired. A #11 blade is used to make stab incisions. It is
often used for the incision and drainage of abscesses, cricothyroidotomies, and the removal of small or tight sutures. A #10 blade is
used to make straight cuts in the skin and debride wound edges. It
is rarely used in laceration repair. A #15 blade is small and curved
to allow precise incisions. It is used for excising foreign bodies and
wound debridement.

SUTURE TECHNIQUES
Proper wound closure requires an understanding of certain basic
principles. The needle should enter and exit the skin at a 90°

angle and perpendicular to the wound edges. By doing so, when
the suture loop is closed, the wound edges will be everted. Sutures
should be placed as close to the wound edge as possible (2 to
3 mm) in order to avoid excessive tension on the wound. More
force will be required to close the wound if the sutures are placed too
far from the wound edge. Edema develops in a wound in the first
48 hours after closure. Sutures placed too far from the wound edge
can result in large scars when the edema subsides.
The layers of the wound should be matched evenly and each
layer should be closed separately. If a wound involves the deeper
layers of skin, fascia should be matched to fascia, dermis should be
matched to dermis, and epidermis should be matched to epidermis.
The proper matching of layers avoids an uneven closure, helps to
prevent an unnecessarily large scar, and eliminates dead space.
The epidermal edges of the wound must be everted to allow
for proper healing. Scars contract with time. They will flatten and

Skin-layer suture size
4–0 or 5–0
6–0 or 7–0
5–0 or 6–0
4–0 or 5–0
3–0 or 4–0
3–0, 4–0, or 5–0
4–0 or 5–0
3–0 or 4–0

Skin-layer closure material
Nylon, polypropylene, or staples
Nylon or polypropylene

Nylon or polypropylene
Nylon or polypropylene
Nylon, polypropylene, or staples
Nylon, polypropylene, or staples
Nylon or polypropylene
Nylon or polypropylene

heal with a better cosmetic result if the wound edge is everted and
slightly elevated. The wound edges will contract into a “pit” below
the plane of the skin, will be more noticeable, and the final result will
be less appealing cosmetically if the wound edges are not everted.
Handle the tissues gently and do not squeeze or twist them too
tightly with the instruments. This helps to avoid strangulation,
which can result in tissue necrosis. The sutures should be placed
carefully and with the proper amount of tension to help promote
healing. Sutures should be snug. Attempts should be made to avoid
excessive tension on the wound edges in order to prevent wound
dehiscence. The use of the smallest suture size necessary to approximate the wound edges will reduce tissue damage and minimize scarring. Table 93-3 lists the appropriate suture types and sizes for each
body region.
If there will be a temporary delay in the closure of a laceration
because of other injuries that may be life-threatening or of greater
importance, cover the wound with a saline-soaked gauze in order to
keep the tissues from drying.

PRINCIPLE OF HALVING
Large wounds gape open and are difficult to approximate. Closure
of the deeper layers will often bring the skin edges into apposition. If
not, the principle of halving may be used to approximate the wound
(Figure 93-2). Identify the midpoint of the laceration. Place the first
suture at the midpoint (Figure 93-2A). This stitch is known as the

central suture. The next sutures are placed in halves on each side
of the central suture (Figures 93-2B & C). Continue the process by
placing sutures halfway between previous sutures until the wound is
approximated. This results in even closure of the wound edge. This
principle can be used for closure of both the deep layers and the skin.

TWO-HANDED SQUARE KNOT
This is the easiest and most reliable method of tying most suture
materials. It involves the classic “right-over-left and left-over-right”

FIGURE 93-2. The principle of halving. A. The first suture is placed in the middle
of the laceration. B. The second suture is placed halfway between the first suture
and the upper end of the laceration. C. The third suture is placed halfway between
the first suture and the lower end of the laceration.


CHAPTER 93: Basic Wound Closure Techniques

tie (Figure 93-3). The incorrect “right-over-left and right-over-left”
is a granny knot, which will slip if it is tied in this manner. This
square knot is quick and simple to perform. However, it does take
significant practice to master this technique.

FIGURE 93-3. The two-handed square knot.

627

Place a suture through the skin on both sides of the laceration
(Figure 93-3A). Pull the suture through the wound until half is
on each side of the laceration. Grasp the right half of the suture

with the right thumb and index finger (Figure 93-3A). Grasp


628

SECTION 7: Skin and Soft Tissue Procedures

FIGURE 93-3. (continued )

the left half of the suture with the left third through fifth fingers
and the suture draped over the thumb (Figure 93-3A). Cross
the right hand toward the left hand (Figure 93-3B). Continue to
move the right hand until the suture is between the left thumb
and index finger (Figure 93-3C). Close the left thumb and
index finger to entrap the right half of the suture in the pads
of the fingers (Figure 93-3D). Pull the right hand down and to
the left so that the two halves of the suture form an X over the
left thumb (Figure 93-3E). Flex the left wrist to slide the X off
the left thumb and onto the left index finger (Figure 93-3F).
Lift the left thumb backward and upward so that the X overlies
the tip of the left index finger (Figure 93-3G). Reapply the left
thumb over the left index finger to entrap the X (Figure 93-3H).
Extend the left wrist to push the left thumb and the X through
the loop (Figure 93-3I). Release the suture held with the right

hand (Figure 93-3J). Regrasp the suture with the right hand after
it passes through the loop (Figure 93-3K). Pull the suture completely through the loop with the right hand. Simultaneously move
the left hand toward the left and move the right hand toward the
right (Figure 93-3L). Cross the hands so that the left hand goes
toward the right side and the right hand goes toward the left side

(Figure 93-3M). Continue to pull both sides of the suture until
the knot lies flat and the skin edges are apposed (Figure 93-3M).
The first half of the knot is now complete.
Make the second half of the knot to complete the square knot.
Raise both hands upward and uncross them until an X is formed
over the left index finger (Figure 93-3N). Close the left thumb
and index finger to entrap the suture being held with the right
hand (Figure 93-3O). Extend the left wrist to push the left thumb
through the loop (Figure 93-3P). Lift the left index finger upward


CHAPTER 93: Basic Wound Closure Techniques

629

FIGURE 93-4. The square knot (A) versus the surgeon’s knot
(B). The first throw of the square knot has one loop (A), while that
of the surgeon’s knot has two loops (B). The second throw of both
knots is a simple loop.

(Figure 93-3Q). Move the right hand away from you until the suture
it holds drapes over the left thumb (Figure 93-3R). Reapply the left
index finger onto the thumb to entrap the suture held with the right
hand (Figure 93-3S). Release the suture held with the right hand
(Figure 93-3T). Flex the left wrist to push the left index finger and
suture through the loop (Figure 93-3U). Regrasp the free suture
with the right hand after it passes through the loop (Figure 93-3V).
Move the right hand upward and to the right to complete the second half of the knot overlying the left index finger (Figure 93-3W).
Simultaneously move the left hand toward the left and move the
right hand toward the right (Figure 93-3X). Continue to pull both

halves of the suture until both halves of the knot come into contact
(Figure 93-3Y). Pull both halves of the suture to secure the knot.
The square knot is now complete. Continue the process to add additional knots onto the suture. Cut off excess suture on both sides of
the knots.

SURGEON’S KNOT
The physician may choose to use a surgeon’s knot instead of a
square knot (Figure 93-4). The square knot has one loop in the first
throw and one loop in the second throw (Figure 93-4A). The surgeon’s knot has two loops in the first throw and one loop in the
second throw (Figure 93-4B). The only difference between these
two knots is the two loops in the first throw. The second throw and
subsequent knots are exactly the same for both knots. The advantage of the surgeon’s knot is that the two loops are more secure and
stay in place while the second throw is being tied. The choice to use
either knot is dependent on the experience and the training of the
physician.

INSTRUMENT TIE
The instrument tie is the most efficient method to complete a simple interrupted suture (Figure 93-5). It is the tie that is most commonly used in the Emergency Department. An instrument tie is
often quicker, requires less dexterity, and is easier to perform than
the two-handed method. It may be used with the square knot or the
surgeon’s knot.

Place a suture through the skin on both sides of the laceration
(Figure 93-5A). Carefully grasp the needle in its midportion and
pull it through the laceration (Figure 93-5B). Continue to pull
the needle until approximately 1 to 2 cm of suture on the tail end
remains outside the laceration (Figure 93-5C). A large amount of
suture will be wasted if the tail is left too long, as it will be later cut
off and discarded. On first learning the instrument tie, it may be best
to leave a tail of 3 to 4 cm until one is proficient with this technique.

Place the needle driver over the laceration but not touching it
(Figure 93-5C). Loosely loop the needle end of the suture over
(Figure 93-5D) and around (Figure 93-5E) the needle driver.
Loosely loop the needle end of the suture over and around the needle driver a second time (Figures 93-5F & G). This will eventually
result in the first half of a surgeon’s knot. Looping the suture once
around the needle driver will result in a simple square knot. Move
the tip of the needle driver toward the tail of the suture without letting the loops fall off the needle driver (Figure 93-5H). Grasp the
tail of the suture with the needle driver (Figure 93-5I). Pull the tail
of the suture through the loop (Figure 93-5J). Pull the tail completely through the loops (Figure 93-5K). Simultaneously move the
left hand toward the right and the right hand/needle driver toward
the left (Figure 93-5L). Continue to pull both sides of the suture
until the hands are opposite each other, the knot lies flat, and the
skin edges are apposed (Figure 93-5M). The first half of the knot is
now complete.
Make the second half of the knot. Continue to hold the needle and release the tail of the suture from the needle driver
(Figure 93-5N). Place the needle driver over the laceration but
not touching it (Figure 93-5N). Loosely loop the needle end of
the suture over (Figure 93-5O) and around (Figure 93-5P) the
needle driver. Move the tip of the needle driver toward the tail
of the suture without letting the loop fall off the needle driver
(Figure 93-5Q). Grasp the tail of the suture with the needle driver
(Figure 93-5R). Pull the tail of the suture completely through
the loop (Figure 93-5S). Simultaneously move the left hand
toward the left and the right hand/needle driver toward the right
(Figure 93-5T). Continue to pull both sides of the suture until
both halves of the knot come into contact. Pull both sides of the
suture to secure the knot. The knot is now complete. Continue


630

SECTION 7: Skin and Soft Tissue Procedures

FIGURE 93-5. The instrument tie.


CHAPTER 93: Basic Wound Closure Techniques

631

FIGURE 93-5. (continued )

this process three or four more times, each in alternative directions, to place additional knots. Cut off the excess suture on both
sides of the knots.

SIMPLE INTERRUPTED STITCH
The simple interrupted stitch is the most commonly used suture
technique and is useful in many situations (Figure 93-6). One major
advantage is that each stitch is placed independent of the others. Therefore tension on each stitch can be adjusted separately.
Additionally, the entire repair is not compromised if one suture
should happen to come out. The other sutures will remain in place
to help assure proper wound healing. The needle must enter and
exit the skin at a 90° angle to help evert the wound edges. Take
equal volumes of skin from each side of the area being sutured.
Drive the needle equidistantly into and out of the wound edges
and incorporate the base of the wound.

Insert the needle at a 90° angle to the skin (Figure 93-6A).
Drive the needle through the tissue until the tip exits the skin
(Figure 93-6B). Grasp the needle behind the tip and pull it

through the wound (Figure 93-6C). The suture should enter
and exit the skin equidistant from the wound edges (Figure
93-6D). If it does not, pull the suture out and repeat the stitch
so that it is equidistant from the wound edges. Make a loop in
the suture with the two-handed tie or the instrument tie. Pull
the suture to appose the wound edges and cinch down the knot
(Figure 93-6E). The tissue at the base of the wound will come
into apposition before the tissue at the skin surface and thus evert
the wound edge. Complete the knot to one side of the laceration
(Figure 93-6F). Just prior to cinching the second throw onto
the first, pull the ends so that the knot is not directly over the
wound and the edges of the wound remain in apposition. Apply
additional sutures equidistant from each other until the wound is
closed (Figure 93-6G).


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SECTION 7: Skin and Soft Tissue Procedures

FIGURE 93-6. The simple interrupted stitch.

OPEN-LOOP SIMPLE INTERRUPTED STITCH
The open-loop simple interrupted stitch is a variation of the simple interrupted stitch (Figure 93-7). The same basic technique is
used except that the knot is tied differently. The tie involves laying
down the first knot with an instrument tie. However, the second
knot placed on the suture is not pulled all the way down. Pull the
second knot only until it is just above the first knot (Figure 93-7A).
In other words, the second knot is loosely tied, leaving a loop
between the first and second knots. Place a third knot as a single

knot square to the second knot (Figure 93-7B). Cinch the third

knot tightly to the second knot. This “locks” the third knot onto
the second knot.
This knot is indicated when there is the possibility of edema forming at the suture site. If edema forms, the first knot will have room
to open as it slides toward the second knot. This stitch avoids excessive tension on the wound and prevents the suture from cutting into
the skin. This stitch facilitates suture removal when numerous small
stitches are placed next to a wound edge. Cutting the open loop
unravels the knot and allows for easy removal of the suture. This
stitch should not be used in areas where the skin is thin or if there
is little subcutaneous tissue (e.g., dorsal hand and foot). In these
areas, the wound edges often become unopposed while the knot is
being secured.

INTERLOCKING SLIP KNOT

FIGURE 93-7. The open-loop simple interrupted stitch.

This technique can be used in patients who will be traveling, camping, or otherwise away from their primary source of medical care
(Figure 93-8). The patient can easily remove the sutures without
having to find an unfamiliar or foreign healthcare provider for routine suture removal. The interlocking slip knot can be removed by
hand without the use of a scissors or a scalpel. This can be useful for
suture removal in pediatric patients, who may find it hard to sit still
for suture removal.
Place a suture through the skin on both sides of the laceration
(Figure 93-8A). Loop the tail end of the suture around the tip
of the needle driver (Figure 93-8A). Grasp the needle end of the
suture with the needle driver (Figure 93-8B). Pull the needle end
of the suture through the loop while simultaneously pulling on the
tail end of the suture with a second needle driver (Figure 93-8C).

Continue to pull both suture halves in opposite directions until a
knot is formed against the skin and the wound edges are apposed
(Figure 93-8D). Release the needle driver holding the now formed
loop. Insert the needle driver through the loop and grasp the tail
end of the suture (Figure 93-8E). Grasp the needle end of the
suture with the second needle driver (Figure 93-8E). Pull the


CHAPTER 93: Basic Wound Closure Techniques

633

FIGURE 93-8. The interlocking slip knot.

needle drivers in opposite directions to lock and secure the knot
(Figure 93-8F). The knot is now complete (Figure 93-8G). To
remove the stitch, pull the free end of the suture to unlock the knot.
Continue to pull the suture until it is free from the skin. This stitch
can easily become loose or open before the wound is healed. Thus,
it is recommended to cover the wound and sutures with skin closure tape (e.g., Steri-Strips).

CONTINUOUS OVER-AND-OVER
STITCH (SIMPLE RUNNING STITCH)
Continuous (simple running) sutures minimize the time required
for laceration repair. Stitches can be placed very quickly, since
each individual stitch does not have to be tied. This stitch provides
strength and applies equal tension on all sutures in the repair. This
stitch can be used to achieve hemostasis. The wound must be long
and straight. Simple running stitches can effectively be used in partial-thickness lacerations and wounds under minimal tension.
However, there are several disadvantages to this stitch. It can

be associated with significant epithelialization of the suture track.
This is especially true if the suture is not removed early and
remains for a prolonged period of time. Inclusion cysts may form
within a few weeks after removal of the sutures. Simple running
stitches should not be used on any wound under tension. If one
suture breaks, the entire wound may open. This stitch should not
be used when closing a wound where there is a risk of subsequent hematoma formation. Hematoma formation would require
the removal of all of the sutures in order to drain the hematoma.
Although this suture is not commonly used in the Emergency
Department, it can be very helpful for closing bleeding scalp
wounds, as the injury will be covered with hair and cosmesis is a
secondary concern.

Place the initial stitch as a simple interrupted stitch (Figure
93-9A). Do not cut the suture after the knots are securely tied.
Place a second stitch 3 to 5 mm from the first stitch as if placing
another simple interrupted stitch (Figures 93-9B & C). Place a
third stitch 3 to 5 mm from the second stitch (Figures 93-9D &
E). Continue to place additional stitches until the end of the laceration is reached. Use care to ensure that the sutures are all lined
up with each other and equidistant from the laceration. Do
not pull the last throw taut against the skin (Figure 93-9F). The
loop will act as the tail end of the suture for knot tying. Loop the
needle end of the suture twice around the tip of the needle driver
(Figure 93-9G). Grasp the last throw with the tips of the needle
driver (Figure 93-9G). Pull the last throw through the loops until
the knot is against the skin (Figure 93-9H). Perform three to five
more instrument ties to secure the knot. Cut off the excess suture
(Figure 93-9I).

CONTINUOUS SINGLE-LOCKED STITCH

(RUNNING-LOCKED CLOSURE)
This stitch may promote less epithelialization of the suture track
than the continuous over-and-over stitch. It maintains the advantages of a continuous suture. This variation of the simple running
closure locks each stitch after it is placed (Figure 93-10). It provides
a secure apposition of the wound edges while each subsequent stitch
is placed. The main disadvantage of this stitch is the time it takes
compared to a continuous over-and-over stitch.
Place the initial stitch as a simple interrupted stitch (Figure
93-10A). Do not cut the suture after the knots are securely tied.
Loop the tail end of the suture over the nondominant fifth finger (Figure 93-10B). Apply slight tension on the tail end of the
suture while placing the second stitch (Figures 93-10C & D).