Acute Pancreatitis

Clinical assessment

Diagnosis requires ≥2 of the following 3 criteria: 1) Characteristic abdominal pain, 2) Serum amylase and/or lipase ≥3 times the upper limit of normal, 3) Characteristic findings on imaging (CT/MRI/Ultrasound). Assess severity (e.g., using scoring systems like Ranson's, APACHE II, BISAP, or presence of organ failure/complications). Differential diagnosis: Perforated peptic ulcer, Acute cholecystitis/cholangitis, Intestinal obstruction/ischemia, Myocardial infarction, Aortic dissection, Diabetic ketoacidosis, Sickle cell crisis.

Investigations

• Serum Amylase and Lipase: Elevated ≥3x ULN is diagnostic (Lipase more specific, stays elevated longer).
• Liver Function Tests (LFTs): ALT/AST, Bilirubin, ALP, GGT (elevated ALT >3x ULN suggests gallstone pancreatitis).
• Complete Blood Count (CBC): Leucocytosis common. Haemoconcentration (raised haematocrit) suggests severe third-spacing.
• Urea, Electrolytes, Creatinine: Assess renal function, dehydration.
• Calcium: May be low (hypocalcemia) in severe pancreatitis.
• Triglycerides: Check if suspected cause.
• Blood Glucose: Hyperglycaemia common.
• Arterial Blood Gas (ABG): Assess oxygenation/acid-base status in severe cases.
• Abdominal Ultrasound: Look for gallstones, biliary dilatation, pancreatic oedema, pseudocysts.
• Contrast-Enhanced CT Scan (Abdomen): Best imaging for assessing severity, detecting necrosis, fluid collections, complications (usually done after 48-72h if severe or diagnosis unclear).

Diagnostic criteria

Requires ≥2 of: Characteristic pain, Lipase/Amylase ≥3x ULN, Imaging findings consistent with pancreatitis.

Non-pharmacological management

• Supportive Care (Mainstay):
• - Fluid Resuscitation: Aggressive early IV fluid resuscitation (Isotonic crystalloids like Ringer's Lactate preferred). Aim for 5-10 ml/kg/hr initially, titrate to maintain adequate urine output (>0.5 ml/kg/hr), heart rate, BP, and reduce haematocrit/BUN.
• - Nil by Mouth (NPO): Initially, until pain subsides and nausea/vomiting resolves.
• - Nutritional Support: Start early enteral feeding (nasogastric/nasojejunal) within 48-72h if tolerated, especially in severe pancreatitis. Prefer low-fat diet initially upon resuming oral intake. Parenteral nutrition reserved if enteral route not feasible.
• - Nasogastric Tube: Only if persistent vomiting or ileus.
• - Monitor: Vital signs, urine output, fluid balance, electrolytes, glucose, abdominal exam.
• - Identify and Treat Underlying Cause: e.g., ERCP for gallstone removal if cholangitis/persistent obstruction.
• - Alcohol/Drug cessation.

Pharmacological treatment

• Pain Control: Crucial. Opioids often required.
• - IV Morphine 1-3mg increments Q4H PRN.
• - OR Pethidine 25-100mg SC/IM or 25-50mg slow IV Q4-6H PRN (note: potential neurotoxicity, less preferred than morphine).
• - Paracetamol (IV/Rectal) may be adjunct.
• - Avoid NSAIDs (risk of renal injury).
• Antiemetics: Metoclopramide 10mg IV/IM Q8H PRN.
• Antibiotics: Prophylactic antibiotics NOT recommended for mild or sterile necrotizing pancreatitis. Use ONLY if specific infection suspected/confirmed (e.g., infected necrosis, cholangitis, UTI, pneumonia). Broad-spectrum agents covering gut flora if needed (e.g., Carbapenems, Piperacillin/Tazobactam, Fluoroquinolone+Metronidazole).
• Insulin: For hyperglycaemia management (target 6-9 mmol/l).
• Electrolyte replacement (e.g., Calcium, Magnesium).

Monitoring

• Vital signs (HR, BP, RR, SpO2, Temp).
• Fluid balance (Intake/Output).
• Pain score.
• Abdominal examination.
• Electrolytes, Renal function (BUN/Creatinine), Glucose, Calcium, Haematocrit.
• Amylase/Lipase (trend may not correlate well with severity after initial peak).
• Monitor for signs of organ failure (respiratory, cardiovascular, renal) and local complications (necrosis, pseudocyst, infection).