Gastrointestinal, Nutritional, and Toxicologic Disorders
GI and liver
Upper GI bleeding: resuscitate, start a proton pump inhibitor, and endoscope early; restrictive transfusion (7 g/dL) improves outcomes. Acute pancreatitis: goal-directed fluids, early enteral nutrition, and treat infected necrosis with drainage rather than early open surgery. Fulminant hepatic failure: lactulose and rifaximin, treat cerebral edema, avoid sedatives, and refer early for transplant.
Nutrition
Start enteral nutrition within 24–48 hours in most ICU patients; trophic feeding is acceptable in shock with escalating pressors. Watch for refeeding syndrome and give thiamine to at-risk patients. Parenteral nutrition carries higher infection risk and is reserved for enteral failure.
Toxicology
Acetaminophen: N-acetylcysteine based on the Rumack-Matthew nomogram at 4 hours or whenever the level will be delayed. Salicylates: alkalinize the urine, dialyze for severe toxicity, altered mental status, or pulmonary edema. Toxic alcohols: fomepizole plus dialysis for severe acidosis. Calcium channel blocker overdose: calcium, glucagon, high-dose insulin euglycemia. Tricyclic overdose: sodium bicarbonate for QRS >100 ms. Digoxin: Fab fragments. Methemoglobinemia: methylene blue. Opioids: naloxone, but avoid flumazenil in mixed overdose.
Traps
- Giving flumazenil in a mixed overdose with a tricyclic.
- Using activated charcoal long after ingestion or in an unprotected airway.
- Forgetting co-ingestants and delayed acetaminophen absorption.
- Overfeeding a malnourished patient and triggering refeeding syndrome.
Rule of thumb
QRS >100 ms with hypotension after overdose means tricyclic until proven otherwise: give sodium bicarbonate.