Acute pancreatitis (GI) Flashcards
Define acute pancreatitis.
Autodigestion of pancreatic tissue by the pancreatic enzymes, leading to necrosis
What are the causes of acute pancreatitis?
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- Idiopathic (10-20%)
- Gallstones (F>M)
- Ethanol (most common worldwide, M>F)
- Trauma
- Steroids
- Mumps
- Autoimmune disease e.g. collagen vascular diseases / Ascaris infection
- Scorpion venom
- Hypertriglyceridaemia, hypercalcaemia, hyperchylomicronaemia, hypothermia
- ERCP
- Drugs (mesalazine, azathioprine, sodium valproate, furosemide, bendroflumethiazide, pentamidine, didanosine)
What drugs can cause acute pancreatitis? (7)
- mesalazine
- azathioprine
- sodium valproate
- furosemide
- bendroflumethiazide
- pentamidine
- didanosine
How can acute pancreatitis be classified? (3)
- mild (80%) - no organ failure, no complications
- moderate - no/transient (<48h) organ failure, possible complications
- severe - persistent (>48h) organ failure, possible complications
Describe the pathophysiology of acute pancreatitis.
- local inflammation of pancreas –> enzyme release –> autodigestion
- abnormal intracellular calcium accumulation –> potentiate colocalization of zymogen and lysosome granules –> premature enzymatic activation
- proteases and inflammatory response can cause leaks in blood vessels and rupture –> excess fluid and pancreatic swelling and bleeding
- activated lipases can destroy peripancreatic fat
- digestion and bleeding can liquify tissue –> liquefactive haemorrhagic necrosis
- ethanol: direct toxic insult to acinar cell –> inflammation and membrane destruction
- causes increase in ductal Pa secondary to protein deposition within the pancreatic duct favouring retrograde flow and intra-pancreatic enzymatic activation
- sphincter of Oddi dysfunction
What is the most likely cause of chronic pancreatitis?
Alcohol
What are the clinical features of acute pancreatitis? (7)
- epigastric pain radiating to the back - constant, severe, sudden, worse with movement
- tender, distended abdomen with voluntary guarding
- nausea and vomiting –> dehydration, electrolyte abnormalities, hypokalaemic metabolic alkalosis
- signs of shock - hypovolaemia (dry mucous membranes, decreased skin turgor, sweating), hypotension, tachycardia
- anorexia
- fever
- signs of pleural effusion - ARDS, reduced air entry, stony dullness on percussion
What can nausea and vomiting in acute pancreatitis lead to? (3)
- dehydration
- electrolyte abnormalities
- hypokalaemic metabolic alkalosis
What signs of shock are seen in acute pancreatitis? (3)
- hypovolaemia - dry mucous membranes, decreased skin turgor, sweating
- hypotension
- tachycardia
What signs of pleural effusion might be seen in acute pancreatitis? (3)
- ARDS
- reduced air entry
- stony dullness on percussion (more commonly on left)
What do we see in severe pancreatitis? (2)
- Cullen’s sign: periumbilical bruising
- Grey-Turner sign: bruising of flanks
What might you see on examination of acute pancreatitis? (5)
- signs of hypovolaemia - oliguria, hypotension, dry mucous membranes, decreased skin turgor, sweating, tachycardia, tachypnoea
- signs of pleural effusion - ARDS, reduced air entry, stony dullness on percussion
- jaundice (severe gallstone pancreatitis)
- signs of hypercalcaemia (Chvostek’s or Trousseau’s sign)
- ecchymotic bruising and discolouration (Cullen’s, Grey Turner’s, Fox’s sign) if haemorrhagic
What are the risk factors for acute pancreatitis?
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- gallstones
- alcohol (F 50-70 or young/middle-aged men)
- trauma
- steroids
- mumps
- autoimmune conditions (SLE, Sjogren’s)
- scorpion venom
- hypertriglyceridaemia and hypercalcaemia
- ERCP (use of contrast –> pancreatic inflammation)
- drugs
What are the main factors indicating severe pancreatitis? (6)
- age >55
- hypocalcaemia (<2mmol/L)
- hyperglycaemia (>10mmol)
- hypoxia (<7.9kPa)
- neutrophilia
- elevated LDH and AST
What criteria is used to determine severity of pancreatitis?
Glasgow score: 3+ means severe pancreatitis
What is the Glasgow score for severity of pancreatitis?
PANCREAS: 3+ –> severe pancreatitis
- PaO2 <7.9kPa
- Age >55
- Neutrophilia
- Calcium <2mmol/L
- Renal function: urea >16mmol/L
- Enzymes –> elevated LDH & AST
- Albumin <32g/L
- Sugar: glucose >10mmol
What are the first-line investigations for acute pancreatitis? (4)
- serum lipase or amylase
- FBC with differential
- CRP
- urea/creatinine
What are serum amylase/lipase like in acute pancreatitis?
Serum lipase or amylase >3x upper limit of normal (in 1000s) - confirms the diagnosis of acute pancreatitis in a patient with acute upper abdominal pain
Which out of serum amylase and lipase is more useful?
Serum lipase:
- lipase levels remain elevated for longer (14d vs 5d for amylase) –> better for diagnosis in delayed presentation
- more sensitive and specific than amylase
What does FBC show in acute pancreatitis? (3)
- leukocytosis with left shift (more immature neutrophils)
- neutrophilia
- elevated haematocrit is predictor of poor prognosis due to increased risk of necrotising pancreatitis
What does urea/creatinine show in acute pancreatitis?
Elevated - suggests dehydration or hypovolaemia
What might LFTs show in acute pancreatitis?
Elevated LFTs suggest gallstones are the cause
What might serum calcium show in acute pancreatitis?
- high
- causative
- whilst hypercalcaemia can cause pancreatitis, hypocalcaemia is an indicator of pancreatitis severity
What imaging is done in acute pancreatitis and why? (4)
- early abdominal US to assess aetiology as this affects management
- contrast-enhanced CT (CECT) - investigating differentials, may also show pseudocyst, inflammation, necrosis
- erect CXR - rule out perforation, may show pleural effusion or elevated hemidiaphragm, atelectasis
- ERCP/MRCP - if gallstones suspected
When can acute pancreatitis be diagnosed without imaging?
Characteristic pain + serum amylase/lipase 3x upper limit of normal
What could a CRP >200 units/L mean in acute pancreatitis?
High risk of developing pancreatic necrosis
What investigation can indicate severity in acute pancreatitis?
Hypocalcaemia on bloods
Describe the diagnostic criteria for acute pancreatitis.
2/3 of the following must be met for diagnosis:
- clinical (upper abdominal pain)
- laboratory (serum lipase or amylase >3x upper limit of normal)
- imaging (CT, MRI, US) criteria
What are signs of systemic inflammatory response syndrome (SIRS) in acute pancreatitis?
At least 2 of:
- heart rate >90bpm
- respiratory rate >20/min (or PaCO2<32mmHg)
- temperature >38C or <36C
- WCC >12x10^9/L or <4x10^9/L
What are some differential diagnoses for acute pancreatitis? (12)
- peptic ulcer disease
- perforated viscus (acute abdomen, peritoneal signs, elevated lipase)
- oesophageal spasm (dysphagia, odynophagia, weight loss)
- intestinal obstruction
- AAA
- choledocholithiasis
- cholecystitis
- cholangitis
- viral gastroenteritis
- hepatitis (jaundice, RUQ pain, anorexia, malaise)
- mesenteric ischaemia (Hx AF and risk factors for PVD)
- MI
What are the key aspects of acute pancreatitis management? (3+1)
- fluid resuscitation
- analgesia with IV opioids
- nutrition
- (consider antiemetic)
How do we fluid resuscitate patients with acute pancreatitis?
- aggressive early hydration with crystalloids
- aim for urine output of >0.5mls/kg/hr
- may help reduce pain by reducing lactic acidosis
What type of nutrition do we give to patients with acute pancreatitis?
- NBM not routinely unless there is a clear reason
- enteral > parenteral
- enteral nutrition normally offered for anyone with moderately-severe or severe acute pancreatitis within 72h of presentation
- parenteral nutrition is used only when EN has failed or is CI
What is the role of Abx in acute pancreatitis?
- there is none
- empirical IV Abx only if infection confirmed or strongly suspected - infected pancreatic necrosis
How can we treat the underlying causes in acute pancreatitis? (6)
- calcium and magnesium replacement therapy
- ERCP: for gallstone pancreatitis with cholangitis
- cholecystectomy: for gallstone pancreatitis without cholangitis
- endoscopic biliary sphincterotomy: if unfit for surgery
- vitamin replacement for alcohol-related pancreatitis: thiamine, folic acid and vitamin B
- admit to ICU
How do we manage patients with acute pancreatitis due to gallstones?
ERCP for gallstone pancreatitis with cholangitis
Cholecystectomy if no cholangitis
When is debridement done for acute pancreatitis?
Patients who fail to settle with necrosis and have worsening organ dysfunction
What do we do in all patients with infected necrosis in acute pancreatitis?
Radiological drainage or surgical necrosectomy
What are some complications of acute pancreatitis? (11)
- acute renal failure
- sepsis
- ARDS/acute lung injury (bilateral pulmonary infiltrates and hypoxaemia)
- pseudocysts - occur 4 weeks after, persistently raised amylase
- pancreatic necrosis
- pancreatic abscess
- abdominal compartment syndrome
- enteric fistulas
- pancreatic ascites/pleural effusion
- haemorrhage
- chronic pancreatitis
What are pancreatic pseudocysts (complication of acute pancreatitis)?
- fibrous tissue surrounds liquefactive necrotic tissue and fills with pancreatic juice
- leads to abdominal pain, anorexia and palpable mass
- infected –> pancreatic abscess (fever, WCC)
- percutaneously drained with endoscopic ultrasound, can be visualised with CT
Describe the prognosis of acute pancreatitis.
- majority of patients improve in 3-7 days of conservative management
- mortality increases in severe pancreatitis
What causes chronic pancreatitis?
Alcohol (mostly)
When is pain worse in chronic pancreatitis?
15-30 mins after meals
What are the symptoms of chronic pancreatitis? (3)
- steatorrhoea (foul-smelling, greasy stool) due to pancreatic insufficiency
- pain
- weight loss
What other condition develops in most patients with chronic pancreatitis?
- DM (>20 years after Sx begin) due to loss of endocrine function
- patients with chronic pancreatitis require HbA1c monitoring every 6 months
What are the main investigations for chronic pancreatitis? (3)
- CT pancreas with IV contrast most sensitive at detecting pancreatic calcification (CECT)
- faecal elastase (low) can also be used to assess exocrine function
- normal amylase
How do we manage chronic pancreatitis? (2 + 5)
Pancreatic enzyme supplements and analgesia
- coeliac plexus block (pain)
- endoscopic/surgical pseudocyst decompression
- pancreatic ductal compression
- extracorporeal shock wave lithotripsy (stones)
- distal pancreatectomy
