Mastering Acute Pancreatitis Guidelines for PLAB 2 Success

Acute pancreatitis is one of the most common gastrointestinal emergencies you'll encounter in PLAB 2. This comprehensive guide covers everything you need to know for exam success, including the latest NICE guidelines and management protocols.

Understanding Acute Pancreatitis

Acute pancreatitis is an acute inflammatory condition of the pancreas that can range from mild, self-limiting disease to life-threatening illness. It's typically caused by gallstones or excessive alcohol consumption, accounting for approximately 40-70% of cases globally.

Key Risk Factors

• Gallstones - Most common cause in the UK

• Alcohol - Second most common cause

• Hypertriglyceridemia - Triglycerides > 1000 mg/dL

• Hypercalcemia

• Drug-induced - Certain medications

• ERCP - Post-ERCP pancreatitis

• Trauma - Abdominal injury

• Infections - Mumps, Coxsackie virus

Clinical Presentation

Classic Symptoms

1. Severe epigastric pain - Radiates to the back, worse when lying flat

2. Nausea and vomiting - Often intractable

3. Fever - Low-grade pyrexia common

Physical Examination Findings

• Grey Turner's sign - Flank ecchymosis (rare)

• Cullen's sign - Periumbilical ecchymosis (rare)

• Abdominal tenderness - With guarding in severe cases

• Reduced bowel sounds - Due to paralytic ileus

• Tachycardia and hypotension - Signs of systemic involvement

Diagnostic Criteria (Revised Atlanta Classification)

For a diagnosis of acute pancreatitis, two of the following three criteria must be met:

1. Acute onset of persistent, severe epigastric pain

2. Serum lipase or amylase levels ≥ 3 times the upper limit of normal

3. Characteristic findings on imaging (CT, MRI, or ultrasound)

Severity Assessment

Mild acute pancreatitis:

• No organ failure

• No local or systemic complications

• Usually resolves within a week

Moderately severe acute pancreatitis:

• Transient organ failure (<48 hours)

• Local complications (pancreatic necrosis, pseudocyst, walled-off necrosis)

Severe acute pancreatitis:

• Persistent organ failure (>48 hours)

• High mortality risk

Initial Investigations

Blood Tests

Imaging

Abdominal ultrasound (first-line):

• Assess for gallstones

• Evaluate bile duct dilation

• Identify pancreatic enlargement

Contrast-enhanced CT (CECT):

• Indicated if diagnosis uncertain

• Best performed 72+ hours after onset

• Assesses for necrosis, collections, complications

MRI/MRCP:

• Better than CT for evaluating pancreatic duct

• Excellent for detecting choledocholithiasis

Management Guidelines

Initial Management (First 24-72 Hours)

1. Aggressive Fluid Resuscitation

• Crystalloids: Normal saline or Ringer's lactate

• Rate: 250-500 mL/hour initially

• Target:

  • Heart rate < 120 bpm

  • Mean arterial pressure > 65 mmHg

  • Urine output > 0.5 mL/kg/hour

  • Hematocrit < 44%

• Caution in patients with cardiac/renal disease

2. Pain Management

• First-line: IV opioids (morphine, fentanyl)

• Consider PCA pump for severe pain

• Avoid NSAIDs (renal risk)

3. Anti-emetics

• Ondansetron IV

• Metoclopramide

4. Oxygen Therapy

• Maintain SpO2 > 95%

• Consider nasal cannula or mask

• ICU referral if PaO2 < 60 mmHg

Nutritional Support

Mild pancreatitis:

• Oral intake once pain resolves and nausea subsides

• Start with clear liquids, advance as tolerated

• Low-fat diet initially

Moderate-Severe pancreatitis:

• Nasogastric feeding if unable to tolerate oral after 72 hours

• Nasoduodenal feeding preferred (less stimulation)

• Enteral nutrition superior to parenteral

• Avoid oral/NG feeding if ileus present

Treating the Underlying Cause

Gallstone pancreatitis:

• Early ERCP (within 24 hours) if:

  • Cholangitis present

  • Persistent biliary obstruction

  • Stone impacted at papilla

• Cholecystectomy during same admission (if fit for surgery)

Alcohol-related:

• Alcohol cessation counseling

• Referral to addiction services

Hypertriglyceridemia:

• Fasting triglycerides < 1000 mg/dL before oral intake

• Consider insulin infusion

• Fibrates for long-term management

Endoscopic Interventions

ERCP indications:

• Biliary sepsis/cholangitis

• Persistent obstruction

• Failed stone extraction on imaging

Pseudocyst drainage:

• If symptomatic (pain, compression)

• Growing in size

• Infection suspected

• Usually endoscopic (transgastric) drainage

Complications

Local Complications

Systemic Complications

• SIRS and MODS

• Acute kidney injury

• ARDS

• Shock (septic or hypovolemic)

• Disseminated intravascular coagulation

• Pancreatic encephalopathy

When to Escalate to ICU

• Persistent organ failure

• Pancreatic necrosis with infection

• Unable to maintain oxygenation

• Hemodynamic instability unresponsive to fluids

• Severe metabolic disturbances

Prognostic Scoring Systems

Ranson's Criteria

On admission:

• Age > 55 years

• WBC > 16,000/mm³

• Glucose > 200 mg/dL

• LDH > 350 IU/L

• AST > 250 IU/L

At 48 hours:

• Hct drop > 10%

• BUN increase > 5 mg/dL

• Calcium < 8 mg/dL

• PaO2 < 60 mmHg

• Base deficit > 4 mEq/L

• Fluid sequestration > 6 L

Interpretation:

• < 3 criteria: Low mortality (<2%)

• 3-4 criteria: Moderate mortality (15%)

• 5-6 criteria: High mortality (40%)

• 6 criteria: Very high mortality (100%)

APACHE II Score

• More complex but more accurate

• Score ≥ 8 suggests severe pancreatitis

Discharge Planning and Follow-up

Before discharge, ensure:

• Tolerating oral diet

• Pain controlled with oral medications

• Mobile and self-caring

Follow-up:

• Outpatient appointment within 4-6 weeks

• Abdominal ultrasound to assess gallbladder

• Alcohol counseling completion

• Consider CT if symptoms persist

PLAB 2 Key Points to Remember

1. Diagnosis requires 2 of 3: Pain, amylase/lipase ≥3x ULN, imaging findings

2. First-line investigation: Abdominal ultrasound

3. CT indication: Uncertain diagnosis, after 72 hours for severity assessment

4. Most important initial step: Aggressive fluid resuscitation

5. Gallstone pancreatitis + cholangitis: ERCP within 24 hours

6. Severe pancreatitis: Nil by mouth, consider NG feeding after 72 hours

7. Pseudocyst: Drain if >6 cm or symptomatic

8. Mortality prediction: Ranson's criteria (3+ = severe)

9. Complications: Necrosis, pseudocyst, systemic organ failure

10. Cholecystectomy: During same admission for gallstone pancreatitis

Summary

Acute pancreatitis management in PLAB 2 focuses on:

• Prompt diagnosis with lipase/amylase and imaging

• Aggressive fluid resuscitation in first 24 hours

• Identify and treat cause (gallstones, alcohol, lipids)

• Monitor for complications and escalate appropriately

• Early enteral feeding when safe

• Definitive treatment before discharge

Master these guidelines, and you'll be well-prepared for any acute pancreatitis scenario in your PLAB 2 exam!

Note: This guide is based on current NICE guidelines and standard medical practice. Always refer to the latest local protocols in the exam.