6.3 GI Bleeding, Motility & Surgical Conditions

GI Bleeding, Motility & Surgical Conditions

Gastrointestinal emergencies account for meaningful morbidity in progressive care, and outcomes hinge on rapid source localization, aggressive resuscitation, and recognizing when a seemingly benign abdominal complaint is actually a surgical emergency.

Upper vs. Lower GI Bleeding

Bleeding is localized anatomically relative to the ligament of Treitz:

• Upper GI bleed (UGIB) presents as hematemesis (bright red or coffee-ground emesis) or melena (black, tarry, foul-smelling stool from digested blood). Common sources include peptic ulcer disease, esophageal or gastric varices, Mallory-Weiss tears, and erosive gastritis.
• Lower GI bleed (LGIB) presents as hematochezia (bright red or maroon stool or blood per rectum). Common sources include diverticulosis, angiodysplasia, inflammatory bowel disease, hemorrhoids, and malignancy.

Massive upper bleeds can also present with hematochezia if transit is rapid, so the presentation alone does not always confirm the source — endoscopy does.

Priorities in Acute GI Hemorrhage

Regardless of source, initial management follows the same sequence: airway protection (especially with active hematemesis and aspiration risk), two large-bore IV lines, aggressive crystalloid resuscitation, and immediate type and crossmatch for possible transfusion. Coagulopathy is corrected — reversing anticoagulants, giving platelets or fresh frozen plasma as indicated — and a proton pump inhibitor infusion is started empirically for suspected upper GI sources while awaiting endoscopy. For variceal bleeding specifically, octreotide reduces splanchnic blood flow and portal pressure, and prophylactic antibiotics reduce infection risk in cirrhotic patients. If variceal bleeding cannot be controlled endoscopically, a balloon tamponade device (Sengstaken-Blakemore or similar) can temporarily compress the bleeding varices as a bridge to a more definitive procedure such as a transjugular intrahepatic portosystemic shunt (TIPS), which reduces portal pressure by creating a channel between the portal and hepatic venous systems. Endoscopy, or colonoscopy for lower sources, is both diagnostic and therapeutic, allowing cautery, clipping, or band ligation of the bleeding site. Risk-stratification tools such as the Glasgow-Blatchford score help identify which upper GI bleed patients need urgent intervention versus outpatient follow-up. Serial hemoglobin and hematocrit, vital signs, and stool or emesis characteristics guide ongoing resuscitation; a falling blood pressure with rising heart rate signals ongoing hemorrhage despite resuscitation efforts. Massive transfusion protocols, which deliver red cells, plasma, and platelets in a fixed ratio, are activated for hemodynamically unstable patients with ongoing major hemorrhage rather than waiting for sequential single-unit transfusions to catch up with ongoing losses.

Motility Disorders and Obstruction

Bowel obstruction may be mechanical (adhesions, hernia, tumor, volvulus) or functional (ileus, from decreased peristalsis without a physical blockage, common postoperatively or with opioid use, hypokalemia, or immobility). Classic signs include abdominal distension, cramping pain, nausea and vomiting, obstipation (absence of stool or flatus), and abnormal bowel sounds — high-pitched and hyperactive early in mechanical obstruction, progressing to absent as the bowel fatigues. Diabetic gastroparesis delays gastric emptying due to autonomic neuropathy, causing early satiety, bloating, and erratic glucose control from unpredictable nutrient absorption; management includes small, frequent, low-fat meals, prokinetic agents, and tight glucose control. Suspected mechanical obstruction is confirmed with an abdominal x-ray (KUB) showing dilated bowel loops and air-fluid levels, or CT imaging for greater detail; initial management includes bowel rest, nasogastric tube decompression to relieve distension and reduce vomiting/aspiration risk, IV fluids to correct losses, and correction of any contributing electrolyte abnormality such as hypokalemia before the underlying cause is addressed surgically or resolves spontaneously.

GI Infections and Ischemic Bowel

Clostridioides difficile infection typically follows antibiotic or proton pump inhibitor use, which disrupts normal gut flora and allows toxin-producing overgrowth, causing watery diarrhea, cramping, and leukocytosis. Because C. diff forms spores resistant to alcohol-based hand sanitizer, care requires contact precautions with soap-and-water hand hygiene for both staff and visitors.

Ischemic bowel (mesenteric ischemia) is a high-mortality surgical emergency classically presenting as severe abdominal pain out of proportion to physical exam findings, often in patients with atrial fibrillation, atherosclerosis, or low-flow states. Rising lactate reflects tissue hypoperfusion and necrosis; delayed recognition allows progression to bowel infarction, perforation, and sepsis, so any mismatch between pain severity and a soft, minimally tender abdomen should prompt urgent imaging and surgical consultation.

Postoperative GI and Bariatric Surgery Care

Patients recovering from bowel resections, esophagogastrostomy, or bariatric procedures require vigilant monitoring for anastomotic leak (fever, tachycardia, increasing abdominal pain, or peritonitis signs), wound complications, and early mobilization to reduce ileus. Bariatric surgery patients carry specific risks including anastomotic leak, marginal ulcer, dumping syndrome, and nutritional deficiencies, and require staged diet advancement per surgical protocol. Recognizing tachycardia as an early sign of a leak — often appearing before fever or pain fully develop — is a key patient-safety point in postoperative GI surgical care. Dumping syndrome, common after gastric bypass, occurs when food moves too rapidly from the stomach into the small intestine; early dumping (within 30 minutes of eating) causes GI cramping and vasomotor symptoms from fluid shifts, while late dumping (1 to 3 hours after eating) causes reactive hypoglycemia from an exaggerated insulin response, and both are managed primarily through dietary modification such as smaller, more frequent, lower-sugar meals.