Gastrointestinal Bleeding

PRESENTATION

1. Hematemesis: Vomiting of blood or altered blood (“coffee

grounds”) indicates bleeding proximal to ligament of Treitz.

2. Melena: Altered (black) blood per rectum (_100 mL blood required

for one melenic stool) usually indicates bleeding proximal to ligament

of Treitz but may be as distal as ascending colon; pseudomelena

may be caused by ingestion of iron,bismuth, licorice,beets, blueberries,

charcoal.

3. Hematochezia: Bright red or maroon rectal bleeding usually implies

bleeding beyond ligament of Treitz but may be due to rapid upper

GI bleeding (_1000 mL).

4. Positive fecal occult blood test with or without iron deficiency.

5. Symptoms of blood loss: e.g.,light-headedness or shortness of

breath.

HEMODYNAMIC CHANGES Orthostatic drop in Bp _ 10 mmHg

usually indicates _20% reduction in blood volume (_ syncope,lightheadedness,

nausea,sweating, thirst).

SHOCK Bp _ 100 mmHg systolic usually indicates _30% reduction

in blood volume (_ pallor,cool skin).

LABORATORY CHANGES Hematocrit may not reflect extent of

blood loss because of delayed equilibration with extravascular fluid. Mild

leukocytosis and thrombocytosis. Elevated BUN is common in upper GI bleeding.

ADVERSE PROGNOSTIC SIGNS Age _60,associated illnesses,

coagulopathy, immunosuppression,presentation with shock,rebleeding,

onset of bleeding in hospital,variceal bleeding, endoscopic stigmata of

recent bleeding [e.g.,“visible vessel” in ulcer base (see below)].

UPPER GI BLEEDING

CAUSES Common Peptic ulcer (accounts for _50%),gastropathy (alcohol,

aspirin,NSAIDs,stress),esophagitis,Mallory-Weiss tear (mucosal tear

at gastroesophageal junction due to retching),gastroesophageal varices.

Less Common Swallowed blood (nosebleed); esophageal,gastric, or intestinal

neoplasm; anticoagulant and fibrinolytic therapy; hypertrophic gastropathy

(Me´ne´trier’s disease); aortic aneurysm; aortoenteric fistula (from aortic

graft); AV malformation; telangiectases (Osler-Rendu-Weber syndrome); Dieulafoy lesion (ectatic submucosal vessel); vasculitis; connective tissue disease

(pseudoxanthoma elasticum,Ehlers-Danlos syndrome); blood dyscrasias; neurofibroma; amyloidosis; hemobilia (biliary origin).

EVALUATION After hemodynamic resuscitation (see below and Fig.

53-1).

• History and physical examination: Drugs (increased risk of upper and lower

GI tract bleeding with aspirin and NSAIDs),prior ulcer, bleeding history, family

history,features of cirrhosis or vasculitis, etc. Hyperactive bowel sounds favor

upper GI source.

• Nasogastric aspirate for gross blood,if source (upper versus lower) not clear

from history; may be falsely negative in up to 16% of pts if bleeding has ceased

or duodenum is the source. Testing aspirate for occult blood is meaningless.

• Upper endoscopy: Accuracy _90%; allows visualization of bleeding site

and possibility of therapeutic intervention; mandatory for suspected varices, aortoenteric fistulas; permits identification of “visible vessel” (protruding artery

in ulcer crater),which connotes high (_50%) risk of rebleeding.

• Upper GI barium radiography: Accuracy _80% in identifying a lesion,

though does not confirm source of bleeding; acceptable alternative to endoscopy

in resolved or chronic low-grade bleeding.

• Selective mesenteric arteriography: When brisk bleeding precludes identification

of source at endoscopy.

• Radioisotope scanning (e.g., 99Tc tagged to red blood cells or albumin); used

primarily as screening test to confirm bleeding is rapid enough for arteriography

to be of value or when bleeding is intermittent and of unclear origin.

LOWER GI BLEEDING

CAUSES Anal lesions (hemorrhoids,fissures),rectal trauma, proctitis, colitis

(ulcerative colitis,Crohn’s disease,infectious colitis, ischemic colitis, radiation),

colonic polyps, colonic carcinoma,angiodysplasia (vascular ectasia),

diverticulosis,intussusception,solitary ulcer, blood dyscrasias, vasculitis, connective tissue disease,neurofibroma, amyloidosis,anticoagulation.

EVALUATION See below and Fig. 53-2.

• History and physical examination.

• In the presence of hemodynamic changes,perform upper endoscopy followed

by colonoscopy. In the absence of hemodynamic changes,perform anoscopy

and either flexible sigmoidoscopy or colonoscopy: Exclude hemorrhoids,

fissure,ulcer, proctitis,neoplasm.

Colonoscopy: Often test of choice,but may be impossible if bleeding is massive.

• Barium enema: No role in active bleeding.

• Arteriography: When bleeding is severe (requires bleeding rate _0.5 mL/

min; may require prestudy radioisotope bleeding scan as above); defines site of

bleeding or abnormal vasculature.

• Surgical exploration (last resort).

BLEEDING OF OBSCURE ORIGIN Often small-bowel source. Consider

small-bowel enteroclysis x-ray (careful barium radiography via peroral

intubation of small bowel),Meckel’s scan,enteroscopy (small-bowel endoscopy),

or exploratory laparotomy with intraoperative enteroscopy.

TREATMENT

Upper and Lower GI Bleeding

• Venous access with large bore IV (14–18 gauge); central venous line for

major bleed and pts with cardiac disease; monitor vital signs,urine output,

Hct (fall may lag). Gastric lavage of unproven benefit but clears stomach

before endoscopy. Iced saline may lyse clots; room-temperature tap water

may be preferable. Intubation may be required to protect airway.

• Type and cross-match blood (6 units for major bleed).

• Surgical standby when bleeding is massive.

• Support blood pressure with isotonic fluids (normal saline); albumin and

fresh-frozen plasma in cirrhotics. Packed red blood cells when available

(whole blood if massive bleeding); maintain Hct _25–30. Fresh-frozen

plasma and vitamin K (10 mg SC or IV) in cirrhotics with coagulopathy.

• IV calcium (e.g.,up to 10–20 mL 10% calcium gluconate IV over 10–

15 min) if serum calcium falls (due to transfusion of citrated blood). Empirical

drug therapy (antacids,H 2 receptor blockers,omeprazole) of unproven benefit.

• Specific measures: Varices: octreotide (50-_g bolus,50- _g/h infusion for

2–5 days),Blakemore-Sengstaken tube tamponade, endoscopic sclerosis, or

band ligation; propranolol or nadolol in doses sufficient to cause beta blockade

reduces risk of recurrent or initial variceal bleeding (do not use in acute bleed)

(Chap. 158); ulcer with visible vessel or active bleeding: endoscopic bipolar,

heater-probe,or laser coagulation or injection of epinephrine; gastritis: embolization

or vasopressin infusion of left gastric artery; GI telangiectases:

ethinylestradiol/norethisterone (0.05/1.0 mg PO qd) may prevent recurrent

bleeding,particularly in pts with chronic renal failure; diverticulosis: mesenteric

arteriography with intraarterial vasopressin; angiodysplasia: colonoscopic

bipolar or laser coagulation,may regress with replacement of stenotic

aortic valve.

• Indications for emergency surgery: Uncontrolled or prolonged bleeding,

severe rebleeding,aortoenteric fistula. For intractable variceal bleeding, consider

transjugular intrahepatic portosystemic shunt (TIPS).