Improved Outcomes in Colon and Rectal Surgery part 2 ppt


Foreword
In Improved Outcomes in Colon and Rectal Surgery, Drs.
Whitlow, Beck, Margolin, Hicks, and Timmcke have assembled
a knowledgeable, expert, and distinguished group of contribu-
tors who additionally have flavored their contributions with their
practical experience and “how I do it” approaches. This volume
is the third in a series dealing with improving outcomes, avoid-
ing complications, and in general improving the lot of patients
who require surgery for conditions of the large bowel, rectum,
and anus.
The stated objective of guiding less experienced surgeons in
avoiding the pitfalls of both commonly encountered complica-
tions and those of rarer occurrence is well met in this volume. It
should be in the library of all neophyte surgeons and deserves to
be read even by experienced practitioners.
The field of colon and rectal surgery is a dynamic one with endo-
scopic and open surgery procedures at a mature stage. With con-
stantly improving laparoscopic techniques, robotic surgery and other
modalities only dreamed about in the past requiring every surgeon
to continue to learn and improve this book fills a visible need.
I congratulate the editors and contributors for assembling an
extremely useable and timely text.
J Byron Gathright, Jr. MD
Chairman Emeritus
Department of Colon and Rectal Surgery
Ochsner Clinic
New Orleans, Louisiana
USA

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
Preexisting conditions
Eric L Marderstein, Siyamek Neragi-Miandoab, and Conor P Delaney
CHALLENGING CASE
A 65-year-old hypertensive male smoker requires a low anterior
resection for treatment of an upper rectal cancer. A CT scan of
the chest, abdomen, and pelvis does not show any distant meta-
static spread and his carcinoembryonic antigen is normal. What
additional preoperative laboratory studies and adjunctive testing
are indicated?
CASE MANAGEMENT
A complete history and physical examination is perhaps the
single most important step for guiding preoperative prepa-
ration. If a cardiac review of systems indicates no symptoms
of ischemia at a high workload, and an electrocardiogram is
normal then no further cardiac testing is necessary. A complete
blood count is indicated because the underlying disease can
cause anemia and serum chemistries are indicated because of
the patient’s hypertension. Although routine laboratory test-
ing is not indicated for most procedures, for patients older
than 60 due to undergo major surgery, they are reasonable in
many situations. If there is no suggestion of bleeding abnor-
malities or liver disease on history and physical examination
then coagulation studies are not required. Pulmonary function
testing, unless the patient has significant pulmonary-attribut-
able shortness of breath or extreme oxygen dependence, is not
necessary. The patient should be counseled to stop smoking
because it may prevent postoperative pulmonary complica-
tions, although several weeks of smoking cessation is required

to obtain measurable benefit.
INTRODUCTION
Part of the attraction of colorectal surgery is the diversity of dis-
eases, patients, and procedures that the surgeon sees on a routine
basis. On one day a surgeon can perform several small outpatient
anorectal procedures on relatively healthy patients, followed the
next day by several major complex intraabdominal operations on
frail elderly patient with significant comorbidities. Such variety
underscores the importance of the preoperative evaluation in
identifying preexisting medical conditions and determining their
effect of the proposed procedure. Knowledge of how preexisting
medical conditions can result in certain patterns of postoperative
complications helps to guide the preoperative evaluation. This
chapter’s recommendations regarding laboratory investigation
and additional testing are, when possible, based on published
evidence of their clinical efficacy and cost-effectiveness. As a
general rule, ordering a myriad of specialized tests or routine
laboratory batteries is expensive and provides low yield. Instead,
testing is designed to quantify the magnitude of the preexisting
medical conditions so they can be optimized in the pre-, intra-
and postoperative period to maximize the chance of a successful
outcome.
HISTORY AND PHYSICAL EXAMINATION
A thorough history includes past and current medical and surgical
history, medications, allergies, family history, functional history,
and review of systems. History and physical examination are
generally more important than laboratory data in the develop-
ment of a treatment plan for anesthesia. Young healthy patients
with an unremarkable history and examination may not need any
anesthesia evaluation for moderate size procedures. The overall

risk of surgery is extremely low in healthy individuals and no
additional benefit is gained from more complex evaluations.(1)
If major surgery is planned, or if patients are elderly or have high
levels of comorbidity, a preoperative anesthesia consult is war-
ranted and appropriately required at many institutions. While the
surgeon needs to play an active role in preoperative risk assess-
ment, it is often very helpful to have an anesthesia consultation
to evaluate the patient solely from the standpoint of surgical risk.
Coordination and cooperation between surgeons and anesthe-
siologist is essential to avoid unnecessary delays and surprises
before the surgery. A patient self-administered questionnaire on
the complexity of their past medical history can act as an effective
primary screening tool to stratify patients for further assessment
before surgery.(2) Evaluation is performed with a combination
of history, physical examination, and selected investigations. In
a large prospective clinical-epidemiological study, Arvidsson and
colleagues found that a standardized assessment before surgery,
by a combination of questionnaires, interview, physical exami-
nation, and selected laboratory testing identified a high propor-
tion of patients who were likely to suffer an adverse event in the
postoperative period.(3)
PREOPERATIVE TESTS
Thorough preoperative assessment of patients can minimize
or prevent postoperative complications.(4) Selective labora-
tory studies can be useful, but routine laboratory tests are often
unnecessary.(5, 6) Ordering a battery of routine preoperative
laboratory studies leads to inefficient clinical practice and is not
cost-effective.(7). In one large study, only 0.22% of routine pre-
operative laboratory studies revealed abnormalities that might
influence peroperative management.(8) Tests ordered in screen-

ing panels are frequently not acted upon before surgery, thereby
creating additional medicolegal risk.(8) When laboratory tests are
felt to be necessary, it is probably safe to use test results that were
performed and were normal within the past 4 months as preop-
erative tests unless there has been an interim change in clinical
status. Anemia is present in approximately 1% of asymptomatic
patients.(8) However, anemia is common following major sur-
gery and the preoperative hemoglobin level predicts postopera-
tive mortality.(9) A baseline hemoglobin level in patients who are
undergoing major surgery that is expected to result in significant
blood loss is useful in postoperative management to differentiate
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improved outcomes in colon and rectal surgery
between acute or chronic blood loss. The frequency of significant
unsuspected white blood cell or platelet abnormalities is also low.
(10) Unexpected electrolyte abnormalities are uncommon and
routine electrolyte determinations are not recommended unless
the patient has a history that increases the likelihood of an abnor-
mality.(8) Premenopausal females at risk should undergo a urine
or blood test for beta-HCG to determine if they are pregnant so
that appropriate precautions are taken during surgery if still indi-
cated. This practice is codified at many institutions to improve
safety and reduce medical liability. Nonetheless, it is all too com-
mon for a lapse in obtaining a pregnancy test to result in a lengthy
delay in the start of surgery. Routine urinalysis to detect disease
(proteinuria, glucosuria, bacteruria), however, is not indicated.
PREOPERATIVE RISK ASSESSMENT USING
SCORING SYSTEMS
Scoring systems assess the patients’ risk for morbidity and mor-
tality taking into account the kind of planned surgical procedure

and the type of anesthesia.(11) These systems generally use data
acquired during prehospital and in-hospital care, while inclu-
sion of the severity of the planned procedure might improve the
predictive value of these systems.(12, 13) Others have tried to
predict the risk anecdotally, suggesting that a surgeon’s general
feeling and personal experience are a good indicator of subse-
quent outcome.(14) Scoring systems can be helpful in coun-
seling the patient and setting their expectations preoperatively
beyond clinical intuition. In addition, well-constructed scoring
systems can be used to compare hospitals and surgeons while
controlling for the known influence of preoperative risk factors
for poor outcome.(15)
American Society of Anesthesiologists (ASA) Classification
The ASA classification system (Table 1.1) has been developed by
anesthesiologists to evaluate patients’ preexisting morbidities
and operative risk. The system is easy to use and is based on his-
tory, physical examination, and the physician’s experience and
it requires no tests.(16, 17) ASA class has been shown to corre-
late with perioperative mortality and morbidity, as well as with
perioperative variables such as intraoperative blood loss, dura-
tion of postoperative ventilation, and duration of intensive care
unit stay.(18–20) The severity of operative procedure, higher
ASA class, symptoms of respiratory disease and malignancy
are predictive of postoperative morbidity.(13) Disadvantages
to use of the ASA score is that its accuracy depends on the
subjective clinical judgment and experience of the attending
anesthesiologist.
POSSUM (Physiologic and Operative Severity Score for
enUmeration of Mortality and morbidity)
POSSUM was developed through multivariate analysis prima-

rily to permit surgical audit for assessment of quality of care.(21)
It calculates expected death and expected morbidity rates based
on 12 physiological variables and six operative variables each of
which are scored 1, 2, 4, or 8 (Table 1.2).(22) POSSUM was devel-
oped as a scoring system for audit, so other factors may need to be
considered when using POSSUM for risk assessment of patients
for surgery.
One concern with POSSUM has been that it may over predict
mortality and morbidity rates by up to six times with a mini-
mum mortality of 1.1%. POSSUM was modified by Portsmouth
to P-POSSUM using a different calculation to reduce the over-
prediciting bias.(23) While some studies found that both
scoring systems overpredicted mortality rates for vascular sur-
gery patients (24, 25), others found that P-POSSUM was a bet-
ter predictor of mortality and morbidity than POSSUM for
vascular (26) gastrointestinal surgery (27), and laparoscopic
colorectal surgery (28).
The CR-POSSUM (Table 1.3) was a modification of POSSUM
designed to assess risk of colorectal procedures. A retrospec-
tive multivariate analysis was performed on more than 6,000
patients operated on in the United Kingdom between 1993 and
2001.(29) The overall mortality for the series was 5.7% and the
CR-POSSUM was more accurate than POSSUM in their valida-
tion patient set. The advent of laparoscopic colorectal proce-
dures may result in CR-POSSUM also overestimating mortality.
A recent report noted that CR-POSSUM overestimated mor-
tality in patients undergoing laparoscopic colectomy, but
accurately predicted mortality in the subset of patients requir-
ing conversion.(30) When these scoring systems were applied
Table 1.1 American Society of Anesthesia (ASA) classification

scheme.
I Normal healthy patient
II Mild systemic disease
III Severe, noncapacitating systemic disease
IV Incapacitating systemic disease, threatening life
V Moribund, not expected to survive 24 hours
‘E’ Emergency
Table 1.2 Parameters for calculation of the POSSUM score.
Physiological Parameters Operative Parameters
Age (years) Operative severity
Cardiac signs/chest x-ray Multiple procedures
Respiratory signs/chest x-ray Total blood loss (ml)
Pulse rate Peritoneal soiling
Systolic blood pressure (mm Hg) Presence of malignancy
Glasgow Coma Score Mode of surgery
Hemoglobin (g/dl)
White cell count (×1012/l)
Urea concentration (mmol/l)
Na+ and K+ levels (mmol/l)
Electrocardiogram
Table 1.3 Parameters for calculation of the CR-POSSUM score.
Physiological Parameters Operative Parameters
Age (years) Operative severity
Cardiac signs/ chest x-ray Urgency of surgery
Pulse rate Peritoneal soiling
Systolic blood pressure (mm Hg)
Urea concentration (mmol/l)
Presence of malignancy
Hemoglobin (g/dl)
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preexisting conditions
to data from a series of U.S. hospitals; the CR-POSSUM was
the most accurate variant, but overestimated mortality by more
than twofold.(31)
National Surgery Quality Improvement Project (NSQIP)
NSQIP was initially started as a way to measure quality of surgical
care at Veteran’s Administration hospitals but the methodology
has spread to the private sector and is embraced by the American
College of Surgeons (ACS-NSQIP). It is a nationally validated,
risk-adjusted, outcomes-based program to measure and improve
the quality of surgical care.(32) The program employs a pro-
spective, peer-controlled, validated database to quantify 30-day
risk-adjusted surgical outcomes, which allows valid comparison of
outcomes among all hospitals in the program. Participating hos-
pitals and their surgical staff are provided with the tools, reports,
analysis, and support necessary to make informed decisions about
improving quality of care. A key lesson from NSQIP was deter-
mining what key preoperative variables influence morbidity and
mortality. By risk-adjusting the outcomes, morbidity and mortal-
ity can be compared between hospitals without the common argu-
ment “my patients are sicker.” The initial studies were performed
on huge numbers of patients with multivariate analysis ranking
certain preoperative conditions/variables as particularly influen-
tial on postoperative complications and mortality. Albumin, ASA
class, disseminated cancer, emergency surgery, age, blood urea
nitrogen, functional status, weight loss, and “do not resuscitate”
order are consistently the most important variables in the analysis.
(33) The program was initially validated using a range of surgi-
cal procedures, but subsequent publications have used the same
methodology to study particular types of operations. For example,

complications and mortality after colectomy for colorectal cancer
depends on identical preoperative variables as the initial validation
set.(34) The program is well respected because a great emphasis
is placed on data integrity and follow-up to identify preoperative
and postoperative events.
DOCUMENTATION
As an increased emphasis is placed on tracking and report-
ing of complications it is critically important to the surgeon
to document well. For risk-adjusted complications to be valid,
preoperative comorbidities must be identified and noted in the
medical record. Without this, the surgeon will not have justi-
fication for elevated complication rates based on preoperative
illness. This will become more important as DRG classification,
and therefore institutional technical reimbursement, becomes
dependent on diagnosis documented at the time of admission
in the near future.
CARDIOVASCULAR DISEASE
Perioperative cardiac complications are among the most feared
of surgical complications because they can result in death. Their
severity spans a wide range from asymptomatic increase in car-
diac enzymes to fatal massive myocardial infarctions. The goal of
preoperative cardiac evaluation is to quantify the likelihood of
a perioperative cardiac event taking into account patient factors
and the proposed operative procedure. The concept of “cardiac
clearance” is flawed and should not be used. In reality, a patient
with a very low cardiac risk is not immune to perioperative cardiac
events and a patient with known severe coronary artery disease
is by no means guaranteed to have a fatal myocardial infarction.
Even in the highest risk patients undergoing complex vascular
surgery, the risk of postoperative cardiac events is only 34%.(35)

The risk of the proposed procedure must be weighed against the
proposed benefit and urgency to be derived from the operation to
permit the surgeon and patient decide about the appropriateness
of proceeding with surgery.
Multiple models have been devised to estimate perioperative
cardiac risk. The Goldman risk model was an early and well-
accepted model for pure determination of cardiac risk for surgery.
(36) The system is easy to use and utilizes relative weighting of
risk factors; however, it was designed several decades ago and has
not been updated for modern practice. Two more modern predic-
tive models include those proposed by Detsky et al. (37) and Lee
et al. (38). The Lee index identified six independent predictors of
cardiac complications: high-risk surgery (procedures with a 5%
or higher risk of cardiac complications—including prolonged
intraperitoneal operations), history of ischemic heart disease, his-
tory of congestive heart failure, history of cerebrovascular disease,
diabetes, and preoperative serum creatinine >2.0 mg/dL. Patients
with 0, 1, 2, or 3 or more criteria were found to have a rate of major
cardiac complications of 0.5%, 1.3%, 4%, and 9% respectively.
The receiver operating curve generated on a validation cohort of
patients was higher for the Lee index versus the Goldman index
and Detsky’s model, indicating higher predictive power.(38)
The American College of Cardiology (ACC) and American
Heart Association have issued evidence-based guidelines for the
evaluation of patients for noncardiac surgery. They are available at
their website (www.acc.org), the National Guideline Clearinghouse
(www.guidelines.gov), and in print.(39)
A cardiac history and physical exam is designed to identify unsta-
ble coronary syndromes, prior angina, recent or past myocardial
infarction, severe valvular disease, decompensated heart failure,

and significant arrhythmias. Presence of a pacemaker or implant-
able cardioverter defibrillator should be noted. Hypertension
should be identified and controlled pre-, intra-, and postopera-
tively. Elevated blood pressure increases myocardial work, stress
and oxygen demand. Interestingly, a randomized trial was unable
to demonstrate a benefit to delay of surgery for the purpose of con-
trol of severe hypertension.(40) Volatile anesthetics and intravenous
medications can remedy the hypertension quickly. Antihypertensive
medications should be taken with a sip of water on the morn-
ing of surgery and resumed postoperatively as soon as possible.
Symptomatic aortic or mitral stenosis should be identified and
evaluated preoperatively. In certain cases, a valve replacement or
percutaneous valvuloplasty will greatly reduce the risk of surgery.
A history of orthopnea, dyspnea on exertion, and paroxysmal noc-
turnal dyspnea are suggestive of congestive heart failure. Pitting
ankle edema, rales on auscultation of the chest, jugular venous dis-
tention, and an S3 gallop on physical examination all support the
diagnosis of heart failure. A chest radiograph showing cardiomegaly
and prominent pulmonary vascularity is supportive. Noninvasive
evaluation of ventricular function and optimization of the con-
gestive heart failure should be achieved before surgery in such
patients.
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improved outcomes in colon and rectal surgery
In patients with existing cardiac disease, recent changes in
symptoms must be identified. Assessment of functional status is
important to determination of preoperative risk. If the patient can-
not or does not achieve an adequate level of activity in their daily
life it may hide the angina or symptoms they would experience
should they reach that level. The surgical stress can cause cardiac

complications in these patients who would appear to be asymp-
tomatic based on preoperative questioning if their functional
status is poor. The Duke Activity Status Index was developed as a
way to correlate a patient’s exercise tolerance with activities that
they can perform in daily life.(41) Peak oxygen uptake on exercise
testing correlates very well with the determination by this self- or
physician-administered questions. The scale defines these daily
activities in terms of metabolic equivalents (METs). Patients who
cannot reach four METs (equivalent to light housework, climbing
a flight of stairs or walk on level ground at 4 mph) would require
additional investigation if it is necessary to determine whether
they are really asymptomatic or not. Patients who can exercise
at a very high MET without symptoms are less likely to harbor
significant cardiac disease.
The ACC has defined a stepwise algorithm to preoperative
evaluation of the patient requiring noncardiac surgery. Surgery
should be cancelled or delayed unless emergent in patients with
unstable or severe angina, myocardial infarction <1 month prior,
decompensated heart failure, significant arrhythmias or severe
valvular disease.(39) Risk stratification for the type of surgical
procedure includes high (>5% reported cardiac risk), intermedi-
ate (1–5%), or low risk. Intraperitoneal procedures are considered
intermediate risk while ambulatory procedures are considered low
risk. Laparoscopic intraperitoneal surgery, although associated
with less pain and postoperative fluid shifts, should be considered
intermediate risk because of the potential need for use of an open
approach depending on intraoperative circumstances. In patients
undergoing low-risk surgery, no further cardiac assessment is
necessary. For patients undergoing intermediate risk surgery, evi-
dence of good functional capacity without symptoms indicates

no further testing is neededbefore surgery. If the functional status
is poor or unknown, presence of one or more clinical risk factors
as defined by Lee (history of coronary artery disease, history of
heart failure, history of cerebrovascular disease, diabetes or renal
insufficiency) then options include noninvasive cardiac testing to
further stratify risk if it will change management. Alternatively,
the operation can proceed with heart rate control pre-, intra-, and
postoperatively. Patients without symptoms and with a normal
cardiac stress test within past 2 years or revascularization in the
past 5 years do not require further evaluation. If no clinical risk
factors are present, the operation can proceed.
The preoperative electrocardiogram (ECG) is not as indispen-
sable as it once was. The prevalence of abnormal ECGs increases
with age.(42) However, multiple studies seem to indicate that the
electrocardiogram alone is a poor independent predictor of post-
operative cardiac complications.(43–45) While ECG abnormalities
indicate an elevated cardiac risk, it loses its independent predictive
power when analyzed with patient clinical characteristics. One of
these studies did indicate particular risk for patients with left or
right bundle branch blocks on their ECG.(46) In certain cases, the
ECG may contribute to an incomplete history as previous silent
myocardial infarction is common.(47) A preoperative baseline ECG
can be important as a baseline, since it can be of significant impor-
tance in identifying postoperative ECG changes.(36) Preoperative
dysrhythmias (>5 premature ventricular contractions/min) and
P-wave abnormalities are predictive of postoperative dysrhythmias.
(48) The recommendations of the ACC are less clear on the value
of a preoperative ECG than other clinical issues. A preoperative
resting 12-lead ECG is recommended for patients with at least one
clinical risk factor who are undergoing intermediate risk proce-

dures or patients with no clinical risk factors who are undergoing
high-risk surgery. Additionally, a preoperative and postoperative
ECG is not recommended for asymptomatic patients undergoing
low risk surgery. The quandary lies with the asymptomatic patient
planned for intermediate risk surgery. If there is any question about
the functional status, an ECG is indicated. By contrast, if the func-
tional status is outstanding and no symptoms are present it could
be argued to omit the test. Lee’s Revised Cardiac Risk Index was
derived in patients 50 years and older so an arbitrary age cutoff here
may be reasonable.
Noninvasive evaluation of ventricular function with echocar-
diography is indicated in patients with dyspnea of unknown ori-
gin, current or prior heart failure with change in symptoms.(37)
Routine evaluation of ventricular function is not recommended.
Preoperative revascularization is generally not indicated before
surgery unless it would have been recommended for the patient
based on their cardiac evaluation, regardless of whether they had sur-
gery planned. The Coronary Artery Revascularization Prophylaxis
(CARP) trial randomized patients with known coronary artery
disease by cardiac catheterization to revascularization versus medi-
cal management before elective vascular surgery.(49) The Dutch
Echocardiographic Cardiac Risk Evaluation Applying Stress Echo-
cardio graphy (DECREASE-V) trial also randomized patients to
revascularization or best medical therapy before vascular surgery.
(50) Both randomized trials failed to show a benefit to revasculari-
zation before surgery when optimal medical treatment was applied.
If percutanous coronary intervention is indicated and performed
before surgery, either angioplasty or bare-metal stents should be
used and drug-eluting stents avoided. Drug eluting stents have a
higher associated restenosis rate when anticoagulation is discontin-

ued early. If possible, waiting 4 to 6 weeks after stent placement is
beneficial because the stent with be at least partially endothelialized
and clopidogrel (Plavix) can be stopped. If possible, aspirin is to be
continued or resumed quickly after surgery.
Perioperative treatment with beta-blockers titrated to a heart
rate of <70 beats per minute to reduce cardiac risk has been studied
in multiple clinical trials. Although some more recent trials have
not demonstrated the pronounced benefit of earlier trials on the
subject, the aggregate conclusion of the multiple studies suggests
benefit with small risk. Preoperative beta-blockade is indicated in
patients having intermediate risk surgery with one or more clinical
risk factors or any patient having vascular surgery. It is not indi-
cated in patients for low-risk surgery or intermediate risk surgery
without clinical risk factors. Some authors argue that effective beta-
blockade obviates the need for additional cardiac testing in certain
intermediate risk patients.(51) Institution of statin-class medica-
tion for patients with one or more clinical risk factors undergoing
intermediate risk surgery should be considered.(52)

preexisting conditions
PULMONARY DISEASE
Postoperative pulmonary complications (PPCs) are equally preva-
lent and contribute similarly to morbidity, mortality, and length
of stay as cardiac complications.(53) They include atelectasis,
pneumonia, bronchospasm, and respiratory failure (mechanical
ventilation for >48 hours). The American College of Physicians
(ACP) issued guidelines for pulmonary risk stratification avail-
able on their website www.acponline.org and www.guidelines.gov.
Several risk factors are known to increase the risk of pulmonary
complications. Even when controlling for other comorbid condi-

tions, evidence suggests that increasing age is a risk for pulmo-
nary complications.(51) Congestive heart failure, although not
a pulmonary condition, increases risk for postoperative pulmo-
nary complications. Functional dependence defined as need for
assistance from another person or devices to perform activities
of daily living was associated with pulmonary complications.(54)
Impaired sensorium is associated with an increased risk of pulmo-
nary complications. While obesity does not seem to be associated
with an increased risk of pulmonary complications, sleep apnea
does appear to confer increased risk.(53) Cigarette smoking greatly
increases the incidence of pulmonary complications compared to
nonsmokers.
Procedure-related risk factors increase the likelihood of pulmo-
nary complications. Incision location (thoracic, upper abdomen,
lower abdomen) has been shown in several heterogeneous studies
to correlate with pulmonary risk, as well duration of surgery (>2.5
hours in some studies and >4 in others).(53) General anesthesia
and emergency surgery have also been found to be associated
with increased postoperative pulmonary complications.
The ACP guidelines suggested that a preoperative chest radiograph
is indicated in patients with known cardiopulmonary disease or those
older than 50 years of age who are undergoing upper abdominal or
abdominal aortic aneurism surgery. Routine chest radiography in
all patients has been shown to be associated in many studies with a
very small number of abnormalities that influenced management
and an even smaller number in patients under the age of 50.(55,
56) It is reasonable however to have a low threshold to order the
test in those patients in whom it is more likely to be abnormal than
an unselected population. This includes patients with a positive
pulmonary review of systems for conditions such as cough, dys-

pnea on exertion, or recent pneumonia or the presence of chronic
lung conditions such as asthma or pulmonary fibrosis.
Pulmonary function testing is an expensive and tricky test to
administer. It has a well-established place in the preoperative
workup of lung resection patients, but there is no clear indica-
tion in the preoperative workup of abdominal surgery patients.
Evidence from several studies suggests that segregating patients
by forced expiratory volume in 1 s (FEV
1
) creates groups with
differing pulmonary complication rates from 14.6% up to 31%
in the highest and lowest group respectively.(53) What is lacking
from these studies is the correlation of the spirometry with clinical
history, physical exam and other findings. The implication is that
poor preoperative spirometry can be inferred from these noninva-
sive means. The few studies that have compared spirometry data
with clinical data have not consistently shown spirometry to be
superior to history and physical examination.(53) The spirom-
etry data do not demonstrate a threshold below which surgery is
prohibitively dangerous. In a study of patients with FEV
1
< 50%
predicted only <15% of patients died or experienced a major
pulmonary complication.(57)
Control of acute and chronic pulmonary illness and cessa-
tion of smoking can help reduce pulmonary complications.(58)
Treatment and clearance of acute pulmonary infection before
surgery is recommended. Smokers have a four-fold higher risk of
pulmonary complications compared to nonsmokers. Several stud-
ies demonstrate that a 4 to 8 week period of smoking cessation with

greatly decrease this risk.(59–61) Anecdotal evidence suggested
that stopping smoking too close to the time of surgery would have
a paradoxical increase in pulmonary complications. While the sal-
utary effect of stopping smoking is difficult to demonstrate until
4 weeks, these same studies do not report a higher complication
rate in those who have recently quit.(59, 61) Optimization of chronic
obstructive pulmonary disease (COPD) and treating any exacerba-
tion with steroids if necessary is advantageous.(56) Laparoscopic
surgery, if possible, is recommended as it was shown in meta-analysis
to have a trend toward lower pulmonary complications.(62)
Asthma can worsen after surgery. Patients with asthma should
be identified preoperatively and their medications reviewed. The
National Asthma Education and Prevention Program has issued
guidelines for management of asthmatics undergoing surgery
(available at www.guidelines.gov and in print).(63) Their pre-
operative lung function should be optimized to their predicted
values or personal best using a short course of steroids if necessary
to achieve this. Patients who received >20 mg of prednisone per
day for more than 3 weeks in the 6 months before surgery should
be assumed to have suppression of hypothalamic—pituitary—
adrenal function and stress dose steroids are indicated. The stress
dose depends on physicians’ experience, the patient’s condition
requiring chronic steroids, the length and dose of preoperative
use of steroids. The stress dose can be tapered to preoperative
dose within 3 days postoperatively.
Postoperative care techniques can reduce pulmonary complica-
tions. Adequate pain control is essential for an effective deep breath-
ing program. Multiple studies have been performed evaluating
various techniques but the consensus guideline indicates that no
lung expansion intervention has been shown superior to another

but any type of prophylaxis is better than none.(58)
RENAL DISEASE
The patient with preexisting renal disease presents a special chal-
lenge to the surgeon. In patients with preexisting renal dysfunction
is important to avoid additional intraoperative or postoperative
injury caused by dehydration or toxic agents. Adequate urine
output is an indication of adequate renal perfusion. Obtaining a
preoperative urinalysis may identify unsuspected urinary tract infec-
tion, diabetes, or renal insufficiency. However, routine urinalysis is
not recommended preoperatively for most surgical procedures.
(64) Careful questioning regarding symptoms of dysuria, hesi-
tancy, nocturia, and feelings of incomplete evacuation may diag-
nose prostatic disease and its complications including early stage
renal dysfunction. Normal renal function is necessary for the
excretion of the nondepolarizing muscle relaxants used for
anesthesia and surgery. Renal function is also a consideration when
choosing postoperative analgesic regimens including nonsteroidal

improved outcomes in colon and rectal surgery
medications such as ketoralac. Age, hypertension, and diabetes
may be indications for preoperative selective renal function test-
ing. Once renal function is compromised, all medications cleared
by kidney must be dose adjusted in a timely manner and care-
fully monitored if needed. Nephrotoxic agents should be avoided
whenever possible. Angiotensin-converting enzyme inhibitors
reduce the renal perfusion and should probably be avoided if
possible.(65) Mild to moderate renal impairment is usually
asymptomatic; the prevalence of an elevated creatinine among
asymptomatic patients with no history of renal disease is only
0.2%.(66) However, it increases with age.(67) Dialysis is neces-

sary in 1% of patients who develop acute renal failure; the 30-day
mortality is high in those patients with acute renal failure com-
pared to those with normal renal function.(68, 69) Risk factors
for acute renal failure include advanced age, baseline renal dys-
function, left ventricular dysfunction, peripheral vascular disease,
and clinical signs of poor cardiac function such as pulmonary
rales.(38, 68)
Patients with end stage renal failure on dialysis require spe-
cial attention. Patients in with end stage renal disease often have
concurrent hypoalbuminemia and anemia resulting in poor
wound healing and increased risk of complications. Krysa et al.
describe a high instance of anastamotic leak in these patients.
(70). Decreased leukocyte and immunologic function result in
increased risks of infection and impaired cellular immunity.(71)
Pulmonary edema and uremic pneumonitis may compromise res-
piratory function.(72) Postoperative ileus may be prolonged and
patients with diverticulosis are at increased risk for acute infection
and perforation.(73) Fluid and electrolyte abnormalities occur
rapidly and require intensified scrutiny to maintain balance. It is
important to know if the patients make any urine preoperatively,
otherwise alternative strategies from postoperative urine volume,
such as central venous pressure measurement, will be necessary
to ensure adequate tissue perfusion. Dialysis can be scheduled on
the preoperative day and again on postoperative day number one.
Acute postoperative dialysis can be provided at any time using
the same indications for acute dialysis in a nonpostoperative
patient. Dialysis can improve abnormalities of hemostasis that
are caused by platelet dysfunction. Abnormal bleeding in dialysis
patients can be improved by platelet transfusion or administra-
tion of desmopressin acetate (DDAVP) increasing the release of

von Willebrand factor from the endothelium.
HEPATIC DISEASE
Operating on patients with significant liver disease is among the
most daunting tasks for the colorectal surgeon. Although the Child-
Pugh classification was originally described to assess the operative
risk in patients undergoing shunt surgery for portal hyperten-
sion, it has implications for other abdominal surgery. This classi-
fication is a scoring scale designed to quantify liver dysfunction. It
utilizes bilirubin, albumin, prothrombin time, presence of ascites,
and presence of encephalopathy to assign points and a subsequent
classification from A to a maximal dysfunction of C. In a classic
review of cirrhotic patients undergoing a variety of elective and
emergent general surgical procedures, Child’s A cirrhosis carried a
10% mortality, Child’s B cirrhosis had a 31% mortality, and Child’s
C cirrhosis was associated with a 76% mortality.(74) In a study of
cirrhotic patients undergoing colectomy, the in- hospital mortality
was 24% with highest mortality for patients with encephalopathy,
ascites, hypoalbuminemia, and anemia.(75)
Suggestion of underlying cirrhosis can be detected at physical
examination. Scleral icterus, jaundice, spider telangiectasia, and
palmar erythema may be present. Early cirrhosis is associated with
an enlarged liver while advanced disease will lead to a small shrunken
liver. Asterixis, or flapping tremor, is a sign of advanced disease.
Ascites can be detected by physical examination. Unexpected liver
enzyme abnormalities are uncommon, occurring in only 0.3% of
patients in one series.(76) In a pooled data analysis, only 0.1% of
all routine preoperative liver function tests changed preoperative
management.(77) Severe liver function test abnormalities among
patients with cirrhosis or acute liver disease are associated with
increased surgical morbidity and mortality, but it is not clear if mild

abnormalities among patients with no known liver disease have a
similar impact.(78) Clinically significant liver disease would most
likely be suspected on the basis of the history and physical exami-
nation; thus, routine liver enzyme testing is not recommended.(8)
In addition, the relationship between an abnormal result and the
risk of perioperative hemorrhage is not well defined.(77, 79)
Patients with liver disease often have disordered and abnormal
coagulation. Decreased production of clotting factors, especially
vitamin K-dependent ones, by the liver will often result in elevated
prothrombin times (PT) or partial thromboplastin times (PTT).
In some cases fresh frozen plasma or vitamin K administration
can correct these abnormalities, at other times the liver disease
is so severe that the coagulopathy cannot be corrected. In addi-
tion, patients with cirrhosis may have portal hypertension and
splenomegaly, resulting in sequestration and a very low platelet
count. It is mandatory to monitor platelet count as well as PT,
PTT preoperatively so that abnormalities can be corrected.
Portal hypertension can result in portosystemic varicies resulting
in significant intraoperative bleeding at sites which are technically
difficult to manage, such as the splenic flexure and the distal rec-
tum. Use of alternate energy sources (such as Liga-Sure
TM
, Valleylab,
Boulder, CO or Enseal
®
, SurgRX, Redwood City, CA) may assist in
reducing intraoperative blood loss in these challenging patients.
Abnormal clotting factors may increase the risk of bleeding from
hemorrhoidal disease in these patients, or actual rectal varices may
be present.

Patients with liver disease are often nutritionally depleted and
have a very low albumin. They may also have ascites present at sur-
gery. Although the ascites can be drained at operation, it generally
reaccumulates rapidly. Our practice is to leave a drain in the abdo-
men perioperatively to assist the fascia to seal, so that the ascites
will not become tense and may be less likely to breach the incision.
Fluid and electrolyte disturbances are common in the patient with
liver disease including sodium retention, potassium losses, and the
development of edema. Fluid and sodium restriction, potassium
supplementation, and the judicious use of diuretics (spironolac-
tone and furosemide) may be necessary.
MALNUTRITION
Malnutrition is a frequent preexisting condition in surgical
patients. Identification of malnourished patients is possible by
clinical history, physical examination, and laboratory parameters.

preexisting conditions
Malnourished patients, who have lost more than 10% of their
bodyweight in the past 6 months, and have an albumin below 3 g/
dL, have increased complication rates after surgery.(80) A serum
albumin of <3 g/dL, transferrin of <200 mg/dL, and total lym-
phocyte count of <1,200 are consistent with at least some level of
nutritional depletion. The enteral route is the preferred route of
improving nutrition as long as there is a functioning gastrointes-
tinal tract. There is moderate evidence that improved preopera-
tive nutritional status can improve the postoperative outcome.
(81) Severely malnourished patients might benefit more from
nutritional support, although this needs to be provided for
approximately 2 weeks to achieve such benefit.(82) Low body
mass index (BMI) (<20 kg/m

2
) and hypoalbuminemia (<2.5 g/
dL) are independently associated with increased risk of morbidity
and mortality after surgery. Patients with decreased albumin lev-
els are also at increased risk for bleeding, renal failure, prolonged
ventilatory support, and reoperation.(83, 84)
IMMUNOCOMPROMISE
The sources of immunocompromise in potential surgical patients
are numerous and may be primary or acquired. Primary immu-
nodeficiencies are relatively rare (1/10,000) and will not be
encountered by most practicing surgeons.(85) Acquired immu-
nodeficiencies are very common and range from mild defects to
complete loss of immune function. Age, malnutrition, obesity,
malignancy, burns, sepsis, trauma, surgery, anesthesia, blood trans-
fusion, diabetes, renal failure, liver disease, splenectomy, radiation,
and foreign bodies all modify the body’s response to invasion.
Drugs including chemotherapeutic agents are probably the most
frequently encountered cause of severe immunocompromise in
surgical patients and are associated with profound neutropenia.
The use of filgrastim, a granulocyte colony-stimulating factor,
has been shown to decrease the duration of neutropenia and
the incidence of infection versus controls in patients undergo-
ing chemotherapy for small cell carcinoma of the lung and other
nonmyeloid malignancy (86, 87) Cook et al. (88) reported that
neutrophil—lymphocyte ratio (NLR) is an indicator of postoper-
ative complications in colorectal surgical patients in critical care
units. An elevated NLR on the first day after an elective colorectal
resection is associated with increased risk of subsequent compli-
cations. NLR calculation does not burden the hospital with addi-
tional cost and can be used to identify patients at high risk of

complications.(88)
HIV/AIDS
When evaluating a human immunodeficiency virus (HIV)
positive patient for surgery it is important to understand the
current state of their disease. This can be obtained by checking
for history of autoimmune deficiency syndrome (AIDS) defin-
ing illness and measuring a CD4 count and HIV viral load. An
absolute CD4 count of <200 or a decreasing ratio of CD4 to
CD8 (normal 1.8–2.2) is associated with severe immunocom-
promise and subsequent risk for viral, fungal, protozoal, and
bacterial infections as well as prolonged wound healing. Newer
drug regimens that include combinations of protease inhibitors
and nucleoside analogs have greatly improved the prognosis for
HIV-infected patients.(89)
METABOLIC DISEASE
Metabolic diseases represent disorders where altered chemical
transformation processes have resulted in abnormal release, stor-
age, synthesis, or degradation of various protein, carbohydrate,
lipid, or other products of metabolic activity. Gout is a generic
term for a number of genetic and acquired conditions mani-
fested by hyperuricemia and the deposition of uric acid crystals
in joints precipitating an acute inflammatory arthritis. Acute
gouty arthritis often follows a precipitating event. Acute gout has
been commonly described in the postoperative setting.(90, 91)
It manifests most commonly on the third to fifth postoperative
day. Treatment consists of joint rest and administration of colchi-
cine or non-steroidal anti-inflammatory agents.(92) A thorough
past medical history including previous attacks of gout will alert
the clinician that the patient is at risk postoperatively. At the first
early signs of an attack it can be treated quickly. Significant delay

can result in impaired ambulation secondary to pain which has
the potential to prolong ileus and delay recovery.
OBESITY
Obesity has reached epidemic proportions in many areas of the
world and obese patients are requiring surgery more and more
commonly. The BMI is a commonly used relationship to measure
obesity and it represents the bodyweight in kilograms divided by
the height in meters squared. A BMI 18–25 is considered normal
while >30 is obese. Obesity has been demonstrated to be a risk
factor for abdominal surgical wound infection.(93) It has not
surprisingly been linked to increased incidence of wound dehis-
cence (94), hernia (95), stoma complications (96). Some studies
indicate a higher anastomotic leak rate for low colorectal or colo-
anal anastamosis in obese patient.(97) Cardiovascular, pulmonary,
and thromboembolic complications are more frequent in obese
patients, often attributable to their comorbid diseases.(98) Obesity
also causes technical difficulties for the surgeon; operative dura-
tion and likelihood for conversion were increased in obese patients
undergoing laparoscopic surgery.(99) It is reasonable as part of the
informed consent process to counsel patients about their elevated
operative risk due to obesity. If possible, they should be encouraged
to lose additional weight before certain types of surgery where a
delay is safe, and indeed may be beneficial (proctocolectomy with
pouch-anal anastamosis, some diverticular resections).
The extensive experience with bariatric surgery has taught us
that sleep apnea is very common in obese individuals. The patient
should be questioned for snoring, apneic episodes, arousals dur-
ing sleep, or daytime somnolence. Physical exam should focus
on evaluation of the airway, neck circumference, tonsil size and
tongue volume. The American Society of Anestheiologists Task

force recommends that if any of these characteristics are present
that suggest sleep apnea then the anesthesiologist and surgeon
should jointly decide whether to: manage the patient periop-
eratively based on clinical criteria alone or obtain sleep studies
during the conduct of a more extensive evaluation in advance
of surgery.(100) Postoperatively supplemental oxygen should
be administered continuously to all patients with sleep apnea
until they are able to maintain their baseline oxygen saturation
while breathing room air. Sleep apnea patients should have con-
tinuous pulse oximetry monitoring until they are no longer at