Pancreatic and Nutritional Pharmacology
Acute pancreatitis management · Enzyme replacement · Somatostatin analogues · Refeeding syndrome · Micronutrient deficiencies
Acute Pancreatitis: Key Pharmacological Decisions
Fluid Resuscitation
Lactated Ringer’s Preferred
- 250–500 mL/hour for first 12–24 hours
- Target: HR <120, MAP >65, urine output >0.5 mL/kg/hour
- Lactated Ringer’s > normal saline (WATERFALL trial: lower SIRS rate)
- Avoid over-resuscitation: abdominal compartment syndrome risk
Antibiotics
Do NOT Use Prophylactically
- Prophylactic antibiotics: no mortality benefit in randomized controlled trials
- Indicate only for: infected pancreatic necrosis or extrapancreatic infection
- Infected necrosis: imipenem or meropenem (pancreatic tissue penetration)
- Empiric use selects resistant organisms and promotes fungal superinfection
Nutrition
Early Enteral > Parenteral
- Start enteral nutrition within 24–48 hours in severe pancreatitis
- Preserves gut barrier; reduces infection complications
- Nasojejunal preferred if nasogastric not tolerated
- Parenteral only if enteral access cannot be established
Somatostatin Analogues and Functional Tumor Management
| Tumor |
Hormone |
Drug |
Key Point |
| VIPoma |
Vasoactive intestinal peptide |
Octreotide or lanreotide |
Controls profuse secretory diarrhea; stabilizes before surgery |
| Glucagonoma |
Glucagon |
Octreotide or lanreotide |
Improves necrolytic migratory erythema and glucose intolerance |
| Carcinoid syndrome |
Serotonin |
Octreotide LAR or lanreotide autogel (monthly) |
Reduces flushing and diarrhea; antiproliferative activity |
| Insulinoma |
Insulin |
Diazoxide (ATP-K+ channel opener) |
Hyperpolarizes beta cells → suppresses insulin secretion; causes fluid retention (add diuretic) |
| Gastrinoma (ZES) |
Gastrin |
High-dose PPI (omeprazole 60–120 mg/day) |
Controls acid hypersecretion; doses far above standard peptic ulcer disease doses |
Refeeding Syndrome and Nutritional Emergencies
Refeeding Syndrome
Hypophosphatemia on Restarting Nutrition
- Mechanism: insulin surge drives PO4, K+, Mg2+ into cells → severe hypophosphatemia
- Risk: BMI <16, >10% weight loss over 2 months, negligible intake >5 days, alcoholism, anorexia
- Danger: respiratory failure (diaphragm weakness), arrhythmias, seizures
- Prevention: correct electrolytes before starting; begin at 10 kcal/kg/day; increase slowly over 4–7 days
- Give thiamine before any glucose in malnourished patients
Micronutrient Deficiencies
High-Yield Presentations
- Thiamine (B1): Wernicke’s (ocular, ataxia, confusion) — give IV before glucose
- Vitamin B12: megaloblastic anemia + subacute combined degeneration; IM hydroxocobalamin if no intrinsic factor
- Folate: megaloblastic anemia, no neuro features; oral folate 5 mg daily
- Iron: microcytic anemia; oral ferrous sulfate; IV iron if oral not absorbed
- Vitamin D: low in exocrine pancreatic insufficiency; supplement to >30 ng/mL
Critical Rule — Thiamine Before Glucose
In any malnourished patient (alcoholism, anorexia, prolonged starvation), give thiamine 100–200 mg IV before any glucose-containing fluid or nutritional support. Glucose without thiamine in a deficient patient precipitates Wernicke’s encephalopathy, which can progress to irreversible Korsakoff syndrome.