Acute pancreatitis Flashcards
Explain the pathophysiology of acute pancreatitis.
- zymogen granules store the pancreatic enzymes and prevent their premature activation
- acing cells synthesise the digestive enzymes of the pancreas
- damage to acing cells or zymogen granules cause pancreatic enzymes to be activated while in the pancreas
- this initiates the inflammatory cascade and activates neutrophils and macrophages
- mediators released from the neutrophils + macrophages increase pancreatic vascular permeability = haemorrhage, oedema and pancreatic necrosis
Explain the pathophysiology of chronic pancreatitis.
- Repeated bouts of inflammation cause by the same process as in acute pancreatitis
- Leads to chronic inflammation and pancreatic fibrogenesis
What are the S+S of acute pancreatitis?
- sudden, severe LUG pain that penetrates to the scapula
- occasionally, it encircles the abdomen
- often show rigidity - N+V
- Tachycardia + tachypnoea
- Fever (>38)
- Bowel sounds often present in the early phase
- Paralytic ileus, causing absent bowel sounds can last for >4 days - useful marker of disease severity - Jaundice (if gallstone related)
- Cullen’s sign
- Grey Turner’s sign
- Hypoxaemia
What are the S+S of chronic pancreatitis?
- Upper abdo pain that feels worse when eating or drinking
- can become constant - N+V
- Weight loss
- Diarrhoea
- Steatorrhea
What are the causes of pancreatitis?
GET SMASHED
- Gallstones
- Alcohol (ethanol)
- Trauma (usually blunt)
- Surgery (or steroids)
- Mumps (or microbiology = viral, bacterial + parasitic infections)
- Autoimmune (SLE + Crohn’s)
- Scorpion venom
- Hyperlipidaemia/ hypercalcaemia/ hypothermia
- Emboli/Ischaemia
- Drugs (azathioprine, furosemide, oestrogen etc)
What are the differential diagnoses for acute pancreatitis?
- Acute mesenteric ischaemia
- Cholangitis
- Duodenal ulcer
- Small bowel perforation/obstruction
- Gastroenteritis
- Rupture/dissected aortic aneurysm
- Gastric cancer
- Pancreatic cancer
- MI
- ARDS
What are the differential diagnoses for chronic pancreatitis?
- Mesenteric artery ischaemia
- Cholangitis
- PUD
- Intestinal perforation
- Chronic gastritis
- Crohn’s
- Gastric cancer
- Pancreatic cancer
- MI
- CAP
What might blood tests show for acute pancreatitis?
- Amylase 3x normal (>1000U)
- Lipase >2000U
- CRP significantly lower (drug-induced acute pancreatitis)
- Raised bilirubin and/or serum aminotransferase (gallstones)
- Hypocalcaemia
- ABG may show hypoxaemia
What imaging should be done when investigating acute pancreatitis?
- AXR:
- increased retroperitoneal fluid will result in no psoas shadow - Erect CXR:
- helps exclude other causes e.g. bowel perforation - US:
- pancreas quire often poorly visualised
- can show a swollen pancreas, dilated CBD and free peritoneal fluid
- useful when looking for gallstones - CT:
- pancreatic swelling, fluid collection and change in density of gland
What is the criteria for the Glasgow Imrie Score in rating the severity of pancreatitis?
P = PaO2 <8kPa A = Age >55 y/o N = Neutrophilia >15 x 10^9 C = Calcium <2 mol/L R = Renal function; urea >16 mol/L E = Enzymes; LDH >600 iu + AST >200 iu A = Albumin <32 g/L S = Sugar >10 mol/L
Score >2 (3+) = high likelihood of severe pancreatitis
What is the criteria for the Ranson Score in rating the severity of pancreatitis?
On admission:
- Age >55 years
- Glucose >11.1 mmol/L
- WBC >16 x 10^3
- Serum AST >250 units/L
- Serum LDH >350 units/L
First 48h:
- Haematocrit fall >10%
- Urea increase ≥5 mg/dL (equivalent to ≥1.8 mmol/L)
- Serum Ca <2.0 mmol/L
- Hypoxaemia - arterial pO2 <60 mm Hg
- Base deficit >4 meq/L
- Estimated fluid sequestration >6 L
Score 3+ = severe pancreatitis
In what situations are the Glasgow Imrie and Ranson scoring systems used in pancreatitis?
Glasgow imrie:
- pancreatitis caused by gallstones and alcohol
- pt presents within 48h of onset
Ranson’s:
- alcohol induced pancreatitis
- only applies after 48h
What is the initial management for mild acute pancreatitis?
- NBM
- IV fluids
- NG tube if severe vomiting
- IV analgesia (benzodiazepines)
- ERCP if gallstones are the cause (although ERCP can cause pancreatitis)
- Lifestyle advice
What is the initial management for severe acute pancreatitis?
- Oxygen 100%, or CPAP with 40-60% O2
- IV fluids (saline to counter 3rd space sequestration)
- NG tube beyond ligament of Treitz
- IV analgesia
- Abx after peritoneal tap and culture (imipenem = good pancreatic penetration)
- If LFTs worsen or there is progressive jaundice = ERCP and gallstone removal
- If infection or necrosis consider surgery + debridement
- If abscess consider percutaneous catheter insertion
What is the initial management for chronic pancreatitis?
- Lifestyle changes
- Drugs to decrease pancreatic stimulate (Octreotide - somatostatin analogue)
- Enzyme supplementation to prevent malabsorption (lipase, CCK)
- Corticosteroids (autoimmune pancreatitis)
- Analgesia
- Surgery (lithotripsy; ERCP; Coeliac plexus block; resection of pancreas; autologous, pancreatic islet cell transplantation)
