Gastrointestinal System >
Pancreatitis
“Inflammation of the pancreas by enzyme-mediated autodigestion”
Risk Factors
- Alcohol
- Gallstones
- Cancer
Aetiology
Mnemonic IGETSMASHED:
- Idiopathic
- Gallstones (most common cause)
- Ethanol (most common cause)
- Trauma
- Steroids
- Mumps – and other infections
- Autoimmune
- Scorpion venum
- Hypercalcaemia, hyperlipidaemia
- ERCP (iatrogenic)
- Sphincterotomy in ERCP can cause localised inflammation and oedema which blocks pancreatic duct and cause backflow
- Drugs
- e.g. azathioprine, ACE-I, statins, metformin, antibiotics (metronidazole, tetracycline), valproic acid, diuretics, sulfasalazine/mesalazine
Pathophysiology
- Premature activation of zymogen granules in pancreas → protease release and autodigestion of pancreatic tissue → inflammation of pancreas → inflammation from activation of the complement cascade
- Damage to pancreatic tissue results in high lipase and amylase concentrations in blood as pancreatic enzymes are released from pancreatic acinar cells
Clinical Presentation
- Signs:
- Low-grade fever
- Tachycardia
- Hypoxia
- Shock/hypovolaemia (low BP, slowed cap refill)
- Quiet/absent bowel sounds
- Jaundice (if gallstone pancreatitis)
- Epigastric tenderness
- Guarding/rigidity
- Symptoms:
- Sudden severe epigastric pain radiating to back
- Pain may be relieved by sitting forwards
- Nausea and vomiting
Investigations
- Initially:
- ECG: indicated for every upper abdo pain and known cardiac Hx
- ABG
- FBC, LFT, U+Es, inflammatory markers
- Diagnosis:
- Ultrasound: to look for gallstones or biliary obstruction
- CT/MRCP
- ↑ Inflammatory markers (CRP, WBC)
- ↑ Serum amylase, lipase
- Serum amylase 3x above the normal upper range
- Scoring systems:
- APACHE II: Used in UHS on the ward and in ICU. Not specific for pancreatitis patients, used to stratify ICU patients
- Modified Glasgow Score: score of 3 or more indicative of severe pancreatitis
- PaO2 < 8 kPa
- Age > 55
- Neutrophils > 15
- Calcium < 2mmol/L
- Renal function – urea > 16
- Enzymes – LDH > 600, AST > 200
- Albumin <32
- Sugar: BG > 10
- Revised Atlanta criteria (for severity scoring) – based on organ failure, local complications, early prognostic signs
- Mild – No organ failure, no local complications, no systemic complications
- Moderate – Transient organ failure (<48hrs), local complications, exacerbation of comorbidity
- Severe – Persistent Organ Failure (>48hrs)
Management
- Supportive management:
- O2
- Aggressive fluid resus – due to SIRS
- 1L bolus followed by 2-3L in 24hrs based on urine output, renal function
- SIRS (systemic response to inflammation) à cytokine storm à leaky capillaries à fluid shift out of intravascular component and sequestration of fluid in third space à hypovolaemic shock
- Urinary catheter – monitor urine output, fluid balance
- Analgesia
- NO EVIDENCE FOR NBM – early oral feeding in first 24h if tolerated
- Essential to optimise nutrition to aid response to systemic inflammation
- Helps pancreas function normally and keeps enterocytes healthy
- NGT/NJT/TPN if oral feeding not tolerated
- Consider early escalation to ITU
- Surgical management:
- ERCP with sphincterotomy, cholecystectomy – if gallstones implicated
- Sphincterotomy: Small cut made in the sphincter of Ampulla of Vater to widen opening and aid drainage of debris/fluid/stones in the duct system
- Surgery for complications e.g. Debridement of pancreatic necrotic tissue
- ERCP with sphincterotomy, cholecystectomy – if gallstones implicated
- Other management:
- Alcohol avoidance
- Smoking cessation
- Oral pancreatic enzyme supplements (Creon) may be needed
Complications
- Organ failure: SIRS, shock, renal failure, ARDS (pancreas inflammation can affect diaphragm and lungs above it)
- Pancreatic oedema or collection
- Pancreatic pseudocyst
- Pancreatic necrosis
- Haemorrhage (pseudoaneurysms) – can be life-threatening/catastrophic
- Due to protease digestion of blood vessels or erosion of adjacent luminal organs around pancreas e.g. duodenum
- Coeliac axis or gastroduodenal artery may be affected
- Usually occurs later during hospitalisation or during procedures
- Splenic or portal vein thrombosis
- Occur due to localised inflammation giving rise to hyperthrombotic state
- The very common and well-recognised complication occurs even in early disease
- Prophylactic anticoagulation
- DIC (disseminated intraarticular coagulopathy)