GI Emergencies

• Audio chapter
  Single-voice audio, listen on the commute.
• ABIM-format MCQs
  5-option vignettes with full wrong-answer teaching.
• Study guide
  Tables, decision trees, primary sources.
• AI tutor
  Chapter-grounded, answers the question you're stuck on.

What this chapter covers

• Section 31.1: Massive UGIB resuscitation

  Massive upper GI bleeding is a resuscitation problem before it is an endoscopic problem, and the early decisions that drive outcome happen in the first hour: airway protection, restrictive transfusion, massive transfusion protocol activation if hemorrhage is ongoing, agent-specific anticoagulation reversal, and prokinetic preparation for endoscopy.

• Section 31.2: Acute LGIB management

  Acute lower GI bleeding is hematochezia or hemodynamically significant melena from a source distal to the ligament of Treitz, and the workup branches sharply on hemodynamic stability rather than on the suspected etiology.

• Section 31.3: Acute mesenteric ischemia

  Acute mesenteric ischemia carries mortality of approximately 50 to 80 percent and has held this high mortality despite advances in imaging, because the clinical presentation is non-specific, bowel infarction occurs within hours of vascular compromise, and the diagnostic instinct is often the wrong one (the patient with severe abdominal pain and a soft abdomen looks like a non-emergent presentation until the lactate rises or the bowel infarcts).

• Section 31.4: Foreign body and food bolus impaction

  Foreign body and food bolus impaction is managed by the ASGE timing categories, which set a removal window by injury risk, plus a small set of special cases (disc batteries, sharp objects, magnets, body packers, food bolus as the EoE gateway).

• Section 31.5: Caustic ingestion and Zargar grading

  Caustic chemistry, Zargar grading, and long-term stricture and cancer risk are covered in Section 5.6.

• Section 31.6: Esophageal perforation and Boerhaave

  Esophageal perforation can be spontaneous (Boerhaave syndrome from forceful vomiting), iatrogenic (post-endoscopic dilation, post-pneumatic dilation for achalasia, post-EGD with stricture biopsy, post-EMR or ESD), traumatic, or from caustic injury or foreign body.

• Section 31.7: Acute colonic pseudo-obstruction (Ogilvie)

  Acute colonic pseudo-obstruction (ACPO, Ogilvie syndrome) is acute massive colonic dilation without mechanical obstruction in a hospitalized patient.

Podcast episodes

1. 01

   GI Emergencies: Massive Upper GI Bleed

   A massive upper GI bleed is a resuscitation problem before it is an endoscopy problem, because the decisions that drive outcome happen in the first hour. The episode follows a man on warfarin and ibuprofen who arrives in shock. It starts with restrictive transfusion and the point where a massive transfusion protocol takes over. It then covers drug-specific anticoagulant reversal and whether it must finish before the scope, erythromycin before endoscopy and tranexamic acid never, and intubation for airway protection. Next come the timing of endoscopy, dual therapy for high-risk stigmata, and embolization or surgery when endoscopy fails. A second patient with an old aortic graft and a herald bleed shows the cause that cannot be missed.

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2. 02

   GI Emergencies: Lower Bleeding and Ischemia

   This episode is organized around one idea: in both lower bleeding and bowel ischemia, the next step depends on stability and on the cause, not on the label. For lower bleeding, the order is to exclude an upper source with the BUN to creatinine ratio, stabilize, do anoscopy, then choose colonoscopy for the stable patient or CT angiography for the unstable one, and clip or band a bleeding diverticulum. Pain before blood points to colon ischemia and, if right-sided, to the mesenteric arteries. Acute mesenteric ischemia follows: recognize pain out of proportion to the examination, get CT angiography despite a normal lactate, resuscitate, then treat by cause or operate for peritoneal signs.

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3. 03

   GI Emergencies: Esophageal Emergencies

   The organizing idea is that urgency follows how fast an injury escalates. The episode starts with a food impaction, where complete obstruction means endoscopy within six hours, glucagon rarely helps, nothing is pushed blindly, and biopsies look for eosinophilic esophagitis. It then moves to the two-hour button battery and the removal windows for sharp, long, wide, magnetic, blunt, and drug-packet objects. Next comes Boerhaave syndrome: the Mackler triad, CT with water-soluble contrast, antibiotics with antifungals in severe disease, and the twenty-four-hour line between primary repair and a covered stent. It ends with caustic ingestion: airway first, what never to do, and the Zargar grade deciding disposition.

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4. 04

   GI Emergencies: Ogilvie Syndrome

   Acute colonic pseudo-obstruction is massive colonic dilation without a mechanical blockage, driven by autonomic imbalance that opioids, surgery, and electrolyte disturbances unmask. The episode follows a 76-year-old man after hip surgery through four ordered steps. First, CT excludes mechanical obstruction, volvulus, and toxic megacolon, and sets a baseline cecal diameter. Second, supportive care corrects electrolytes, stops opioids, and decompresses with tubes, resolving about 80 percent of cases. Third, a cecum over 12 centimeters or persistent distension triggers neostigmine, given on a monitor after contraindications are checked. Fourth, colonoscopic decompression follows if neostigmine fails or is contraindicated, and surgery is reserved for perforation, peritonitis, or failure of everything else.

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Key topics

• ·Resuscitation before endoscopy
• ·Restrictive transfusion thresholds
• ·Massive transfusion protocol and calcium
• ·Anticoagulant reversal
• ·Reversal and the timing of endoscopy
• ·Erythromycin and tranexamic acid
• ·Airway protection before EGD
• ·Timing of endoscopy
• ·Dual therapy, embolization, and surgery
• ·Aortoenteric fistula and the herald bleed
• ·Excluding an upper source in lower bleeding
• ·Anoscopy and stabilization
• ·Oakland score and disposition
• ·CT angiography versus colonoscopy
• ·Diverticular bleeding and clips
• ·Post-polypectomy bleeding and angiodysplasia
• ·Colon ischemia severity and antibiotics
• ·Acute mesenteric ischemia recognition and CT angiography
• ·Resuscitation without vasopressors
• ·Embolus, thrombosis, nonocclusive and venous causes
• ·Food bolus impaction and the six-hour rule
• ·Glucagon and blind pushing
• ·Eosinophilic esophagitis biopsies
• ·Button battery and the two-hour clock
• ·Removal windows by object type
• ·Drug packets
• ·Boerhaave syndrome and the Mackler triad
• ·CT, antibiotics, and antifungals
• ·Repair versus stent at twenty-four hours
• ·Caustic ingestion and Zargar grades