Acute Pancreatitis

History and Presentation

Abdominal pain

• Epigastric pain often radiating to the back
• Severe pain
• Sudden onset
• Exacerbating with movement - often relieved when assuming the feral position
• Generalised pain with peritonism if peritonitis is present

Acute gallstone pancreatitis

• Pain may be sudden and knife-like
• Pain often starts after a large meal.

Alcohol-related acute pancreatitis

• Pain may be of less abrupt onset and poorly localised
• Enquire about alcohol history

Other symptoms:

• Nausea
• Anorexia
• Vomiting

Differentials

Perforated peptic ulcer, bowel obstruction, or ischaemic bowel
Ruptured abdominal aortic aneurysm
Myocardial infarction
Biliary colic, acute cholecystitis, or cholangitis
Acute Gallstones and Cholecystitis
Viral hepatitis

Vital Signs

Detect signs of shock:

• HR: Tachycardia
• BP: Hypotension

Examination

• Abdominal tenderness — ranges from mild tenderness in the upper abdomen to generalized peritonitis, rebound tenderness, and guarding in more severe attacks
• Abdominal distension - caused by leakage of fluid into the retroperitoneum in an effort to dilute pancreatic enzymes, causing the abdominal contents to be pushed forward
• Cullen's sign or Grey-Turner's sign - associated with haemorrhagic pancreatitis

Laboratory investigations

• Serum lipase - 3 times the upper limit of normal
• Serum amylase - 3 times the upper limit of normal
• Serum lipase:amylase - >5
• LFTs - AST/ALT ratio >3 times the upper limit of normal predicts gallstone disease
• FBC - detects leukocytosis
• CRP - >200 units/L associated with pancreatic necrosis
• haematocrit - >44% on admission associated with pancreatic necrosis

Radiological investigations

• Abdominal X-Ray
  • Sentinel loop (isolated dilatation of a segment of gut) adjacent to the pancreas
  • Cut-off sign
  • Calcifications
• Chest X-ray
  • Atelectasis
  • Pleural effusion (especially left-sided)
• Abdominal ultrasound
  • Pancreatic inflammation
  • Calcifications
  • Fluid collections

If acute pancreatitis is caused by suspected or proven gallstones:

• Endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy to relieve the obstruction for those with cholangitis, within 72 hours of the onset of pain
• Cholecystectomy performed during the same admission

Management

Initial resuscitation

• IV fluid hydration with crystalloids
  • 0.5 to 1 mL/kg/hour
  • Catheterise patient to monitor urinary output. Maintain urinary output above 30 mL/hour to prevent kidney damage
• Oxygen therapy
• Analgesia
• Antibiotics for treatment of associated cholangitis or acute infections, such as chest infection or urinary tract infection.
• Early nutritional support
  • Commence oral feeding in people with mild acute pancreatitis if there is no nausea, vomiting, or abdominal pain.
  • Otherwise begin enteral feeding
  • Parenteral feeding is reserved for people in whom enteral nutrition is not possible

Percutaneous catheter drainage in cases of infected pancreatic necrosis
Benzodiazepines for those with alcohol induced pancreatitis

Complications

• Pancreatic necrosis
• Pseudocysts
• Pancreatic abscesses
• Pancreatic fistulae
• Pre-hepatic portal hypertension

Systemic complications

• Acute renal failure
• Multiple organ dysfunction
• Acute respiratory distress syndrome
• Disseminated intravascular coagulation
• Sepsis

Prognosis

• Mild acute pancreatitis has a mortality rate of 1%.
• Severe acute pancreatitis has a mortality rate of 10% with sterile pancreatic necrosis
  • This increases to 25% with infected pancreatic necrosis