Acute Gastrointestinal Bleeding

Acute gastrointestinal bleeding ranges in severity from a single, nearly inconsequential bleeding episode, perhaps resulting in vomiting of “coffee-ground” material or the brief passage of red-colored stool, to massive hemorrhage and shock. Chronic or occult gastrointestinal bleeding is discussed in Chapter 44.

Gastrointestinal bleeding is generally classified as either upper or lower in origin (Table 14-1) simply because the source of bleeding is only rarely in the jejunum or ileum and also because the presenting signs and symptoms frequently are characteristic of either an upper or a lower gastrointestinal source. Regardless of the source, however, the principles of the initial management of all patients with acute gastrointestinal bleeding are generally the same (Table 14-2). Because patients vary in the severity of bleeding, the orderly sequence of history taking, physical examination, diagnostic evaluation, and treatment may have to be altered to meet the immediate demands.

I. INITIAL MANAGEMENT

A. History

1. Vomiting or passage of blood per rectum.

The action of gastric acid on blood quickly forms dark particles that resemble coffee grounds. Vomiting of red blood (hematemesis) or of coffee-ground-appearing material usually signifies a source of bleeding in the esophagus, stomach, or duodenum, but it can result from swallowed blood from the respiratory tract. On the other hand, passage of red- or maroon-colored stool per rectum (hematochezia) usually indicates that the source is in the rectum, colon, or terminal ileum.

TABLE 14-1 Diagnostic Considerations in Acute Gastrointestinal Bleeding

Upper gastrointestinal bleeding	Lower gastrointestinal bleeding
Bleeding from nose or pharynx	Hemorrhoids
Hemoptysis	Anal fissure
Esophagogastric (Mallory-Weiss) mucosal tear	Inflammatory bowel disease (proctitis
Esophageal rupture (Boerhaave’s syndrome)	or colitis)
Inflammation and erosions (esophagitis, gastritis,	Neoplasm (carcinoma or polyps)
duodenitis)	Diverticulosis
Peptic ulcer of esophagus, stomach, duodenum,	Ischemic enteritis or colitis
or surgical anastomosis	Angiodysplasia
Dieulafoy’s lesion (ruptured mucosal artery)	Antibiotic-associated colitis
Varices of esophagus, stomach, or duodenum	Radiation colitis
Neoplasm (carcinoma, lymphoma, leiomyoma,	Amyloidosis
leiomyosarcoma, polyps)	Meckel’s diverticulum
Hemobilia	Vascular-enteric fistula
Vascular-enteric fistula (usually from aortic aneurysm or graft)	Brisk bleeding from an upper gastrointestinal source

TABLE 14-2 Principles of the Initial Management of Acute Gastrointestinal Bleeding

I.	Perform in order determined by activity of bleeding
	A.	History
	B.	Vital signs, including postural signs
	C.	Physical examination, including rectal examination
	D.	Insertion of large-bore peripheral venous catheter and, if necessary, a central venous line
	E.	Withdrawal of blood for initial laboratory studies
	F.	Administration of intravenous electrolyte solutions and blood
II.	Pass a nasogastric tube
	A.	If clear initially or clears promptly with lavage, remove
	B.	If bloody, leave in to monitor gastrointestinal bleeding and to provide access to the gastrointestinal tract
III.	Survey for concomitant heart, lung, renal, liver, or central nervous system disease
IV.	Consult a gastroenterologist, a surgeon, and, if indicated, a radiologist
V.	Make a diagnosis (see section II and Figs. 14-1 and 14-2)

However, an important exception is the upper gastrointestinal lesion that bleeds profusely, such as a ruptured esophageal varix or an eroded vessel within a peptic ulcer, in which a large volume of blood passes rapidly through the intestines and appears as hematochezia. The passage of black stool (melena) usually indicates a more moderate rate of bleeding from an upper gastrointestinal source, sometimes as little as 50 mL per day, although bleeding from the terminal ileum or ascending colon can result in melena.

2. Age of patient.

Advanced age worsens the prognosis of acutely bleeding patients. The age of the patient also makes some diagnoses more or less likely, particularly with regard to lower gastrointestinal bleeding. The differential diagnosis of acute lower gastrointestinal bleeding in people over age 60 includes ischemic colitis, carcinoma of the colon, arteriovenous malformation, and diverticulosis, whereas none of these is a serious consideration in a 25-year-old. On the other hand, bleeding from inflammatory bowel disease or a Meckel’s diverticulum is more likely in a child or young adult.

3. Ingestion of gastric mucosal irritants.

The recent ingestion of aspirin, other nonsteroidal antiinflammatory drugs, or alcohol raises the possibility that erosive gastritis or other mucosal injury has developed. Aspirin not only causes direct mucosal injury, but also interferes with platelet adhesion; thus, bleeding lesions in patients who take aspirin are less likely to clot.

4. Associated medical conditions.

The number of associated medical conditions directly increases the risk of mortality in acute gastrointestinal bleeding. Mortality in patients with no accompanying medical conditions is about 1%, whereas the risk of dying in patients with four or more associated illnesses is more than 70%.

Patients with liver disease are at risk to develop esophageal varices, which could bleed. Although acute upper gastrointestinal bleeding in patients known to have esophageal varices is most likely caused by the varices, other sources must be considered.

Previous abdominal or pelvic irradiation raises the possibility that lower gastrointestinal bleeding is caused by radiation enteritis or colitis. Gastrointestinal bleeding may develop from the acute effects of irradiation on the gut, or bleeding may occur months to years later. The latter situation represents a form of ischemic colitis that is accelerated by the perivascular inflammation that results from the effects of irradiation.

Knowledge of serious cardiovascular, pulmonary, liver, renal, or neurologic disease may be valuable in guiding medical and, if necessary, surgical decisions during subsequent treatment of the patient.

B. Physical examination

The physical examination is unlikely to indicate a precise cause of bleeding. However, coolness of the extremities, palmar creases, and pallor of the conjunctivae, mucous membranes, and nail beds may be evident as a result of blood loss and peripheral vasoconstriction. The signs of chronic liver disease or abdominal tenderness may provide relevant information.

2. The rectal examination

is important and should not be omitted, even in seemingly obvious upper gastrointestinal bleeding. The anus, perianal area, and lower rectum can be assessed, as can the character and color of the stool.

Occult blood in the stool can be detected with as little as 15 mL of blood loss per day. Stools may remain positive for occult blood for nearly 2 weeks after an acute blood loss of 1,000 mL or more from an upper gastrointestinal source.

3. Postural signs.

As the patient loses intravascular volume due to blood loss, cardiac output and blood pressure fall, and pulse rate increases. Under conditions of severe volume loss, postural compensation of blood pressure and pulse are inadequate. Thus, so-called postural signs are present if, when the patient sits from a supine position, the pulse rate increases more than 20 beats per minute and the systolic blood pressure drops more than 10 mmHg. Under these circumstances, it is likely that blood loss has exceeded 1 L. However, age, cardiovascular status, and rate of blood loss all influence the development of postural signs.

C. Fluid, electrolyte, and blood replacement

A large-bore intravenous catheter should be inserted promptly into a peripheral vein. Blood can be drawn at this time for laboratory studies (see section I.D). In a profusely bleeding patient, a single peripheral intravenous catheter may not be sufficient to provide adequate blood replacement; two or more intravenous catheters may be required. In an acute emergency in which a peripheral vein is not available, venous access should be established via a jugular, subclavian, or femoral vein.

2. Infusion of fluids and blood.

Normal saline is infused rapidly until blood for transfusion is available. In patients who have excess body sodium, such as those with ascites and peripheral edema, the physician may be reluctant to infuse large amounts of saline. In those instances, the restoration of hemodynamic stability should take precedence over other considerations. In other words, if the patient is bleeding profusely and blood for transfusion is not yet available, saline should be infused without regard for the patient’s sodium balance. If bleeding is less severe, hypotonic sodium solutions may be infused until blood for transfusion arrives. Appropriate treatment of acute gastrointestinal bleeding includes not only replacement of blood, usually in the form of packed red cells, but also infusion of supplemental electrolyte solutions and, when necessary, clotting factors.

3. A central venous pressure catheter or Swan-Ganz catheter

may be necessary to evaluate the effects of volume replacement and the need for continued infusion of blood, particularly in elderly patients or patients with cardiovascular disease.

4. Monitoring of urine output

provides a reasonable indication of vital organ perfusion. In severely ill patients, a urinary catheter may be necessary.

D. Laboratory studies

1. Initial blood studies

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