Chapter 042. Gastrointestinal Bleeding (Part 1) pdf

Chapter 042. Gastrointestinal
Bleeding
(Part 1)

Harrison's Internal Medicine > Chapter 42. Gastrointestinal Bleeding
Gastrointestinal Bleeding: Introduction
Bleeding from the gastrointestinal (GI) tract may present in five ways.
Hematemesis is vomitus of red blood or "coffee-grounds" material. Melena is
black, tarry, foul-smelling stool. Hematochezia is the passage of bright red or
maroon blood from the rectum. Occult GI bleeding (GIB) may be identified in the
absence of overt bleeding by a fecal occult blood test or the presence of iron
deficiency. Finally, patients may present only with symptoms of blood loss or
anemia such as lightheadedness, syncope, angina, or dyspnea.
Sources of Gastrointestinal Bleeding
UPPER GASTROINTESTINAL SOURCES OF BLEEDING
(Table 42-1) The annual incidence of hospital admissions for upper GIB
(UGIB) in the United States and Europe is ~0.1%, with a mortality rate of ~5–
10%. Patients rarely die from exsanguination; rather, they die due to
decompensation from other underlying illnesses. The mortality rate for patients
<60 years in the absence of major concurrent illness is <1%. Independent
predictors of rebleeding and death in patients hospitalized with UGIB include
increasing age, comorbidities, and hemodynamic compromise (tachycardia or
hypotension).

Table 42-1 Sources of Bleeding in Patients Hospitalized for Upper GI
Bleeding in Years 2000–2002

Sources of Bleeding

Proportion of Patients, %

Ulcers

31–59
Varices

7–20
Mallory-Weiss tears 4–8

Gastroduodenal erosions

2–7

Erosive esophagitis 1–13

Neoplasm 2–7

Vascular ectasias 0–6

No source identified 8–14


Source:
Data from M Van Leerdam et al: Am J Gastroenterol 98:1494, 2003; DM
Jensen et al: Gastrointest Endosc 57:AB147, 2003; KC Thomopoulos et al: Eur J
Gastroenterol Hepatol 16:177, 2004; F Di Fiore et al: Eur J Gastroenterol Hepatol
17:641, 2005.
Peptic ulcers are the most common cause of UGIB, accounting for up to
~50% of cases; an increasing proportion is due to nonsteroidal anti-inflammatory
drugs (NSAIDs), with the prevalence of Helicobacter pylori decreasing. Mallory-
Weiss tears account for ~5–10 or 15% of cases.

The proportion of patients bleeding from varices varies widely from ~5 to
30%, depending on the population. Hemorrhagic or erosive gastropathy (e.g., due
to NSAIDs or alcohol) and erosive esophagitis often cause mild UGIB, but major
bleeding is rare.