Pancreatitis Flashcards
How does the pancreas protect itself from autodigestion : acute pancreatitis
Proteases released as inactive pro-enzymes
Pancreas contains trypsin inhibitor to prevent activation of trypsin
Enzymes only activated in duodenum
What is the brush border enzyme that converts trypsinogen?
Enterokinase
What is acute pancreatitis?
Rapid onset inflammation of the pancreas vs chronic long standing inflammation
Acute pancreatitis Aetiology?
GET SMASHED
Gall stones
Ethanol
trauma
steroids
mumps / virus
auto-immune ( polyarteritis nodosa )
scorpian/snake bite
hypercalcaemia, hypertriglyceridaemia, hypothermia
ERCP
Drugs ( steroids, sulphonamides, azothioprine, NSAIDS, diuretics )
Pathogenesis of acute pancreatitis?
↑ permeability of pancreatic duct epithelium (Alcohol, acetylsalicylic acid, histamine)
Acinar cell enzymes diffuse into periductal interstitial tissue
Alcohol ppts proteins in ducts → ↑ upstream pressure
Pancreatic enzymes activated intracellularly
proenzymes & lysosomal proteases incorporated into same vesicles → trypsin activated
5 mechanisms of pancreatitis?
Pressure increase
Bile reflux
Reflux of activated enzymes from duodenum
Enzyme diffusion
Premature activation
What can trypsin activation cause?
hypocalcemia
Hyperglycemia
Pancreatic gangrene
Pain
shock
hypoxia
anuria
What types of acute pancreatitis are there?
Oedematous
haemorrhagic
Necrotic / infected necrosis
Clinical symptoms of acute pancreatitis?
Epigastric pain radiating to back
often eased by sitting forward
N&V (vomiting +++)
Fevers
Clinical signs of acute pancreatitis?
Haemodynamic instability (tachycardic, hypotensive)
Peritonism in upper abdomen/generalised
Grey-Turner’s sign (bruising in flanks)
Cullen’s sign (bruising around umbilicus)
(Grey Turner’s & Cullen’s signs seen in heamorrhagic pancreatitis
Differential diagnosis of acute pancreatitis?
Gallstone disease & associated complications (e.g. biliary colic & acute cholecystitis)
Peptic ulcer disease/perforation
Leaking/ruptured AAA
Investigations for acute pancreatitis?
Blood tests Amylase/lipase other causes of ↑ amylase include: Parotitis renal failure Macroamylasaemia bowel perforation lung/ovary/pancreas/colonic malignancies can produce ectopic amylase)
X rays
Erect CXR
AXR (sentinal loop, GS)
Investigations
USS
look for GSs as cause for pancreatitis
CT abdomen
patients not settling with conservative management & only 48-72 hrs after symptom onset
MRCP
If GS pancreatitis suspected with abnormal LFTs (CBD stone)
ERCP
To remove CBD GS
Assess severity of Acute P with Glasgow criteria?
PO2 <8KPa
age >55yrs
WCC >15
calcium <2mmol/L
renal: urea >16mmol/L
enzymes: AST >200iu/L, LDH >600iu/L
Albumin <32g/L
sugar >10mmol/L
Score of 3 or > within 48hrs of onset - suggests severe pancreatitis
CRP is an independent predictor of severity
>200 suggests severe pancreatitis
Management of acute pancreatitis?
Fluid resuscitation (IV fluids, urinary catheter, strict fluid balance monitoring)
Analgesia
Pancreatic rest (+/- nutritional support if prolonged recovery [NJ feeding or TPN])
Determining underlying cause
95% settle with conservative treatment
If severe pancreatitis on scoring –> HDU
Antibiotics controversial –> commence if necrotic pancreatitis/infected necrosis, but not routinely
Surgery only very rarely required
Systemic complications of acute pancreatitis?
Hypocalcaemia
lipase → FFAs → chelate Ca2+ salts → ↓ serum levels (saponification)
Hyperglycaemia (diabetes if significant beta cell damage)
SIRS (Systemic Inflammatory Response Syndrome)
ARF (Acute Renal Failure)
ARDS (Adult Respiratory Distress Syndrome)
DIC (Disseminated Intravascular Coagulation)
MOF (Multi Organ Failure) & death
Local complications of acute pancreatitis?
- Pancreatic necrosis +/- infection (infected necrosis)
- Pancreatic abscess
- Pancreatic pseudocyst
- Haemorrhage: due to bleeding from erroded vessels
Small vessels –> haemorrhagic pancreatitis (Cullen’s/Grey Turner’s sign)
Large vessels (e.g. Splenic artery)
–> life threatening bleed (unless forms pseudoaneurysm)
Thrombosis of splenic vein, SMV, portal vein (in order of frequency)
- > ascites - > small bowel venous congestion/ischaemia
Chronic pancreatitis/pancreatic insufficiency (if recurrent attacks)
How to manage infected necrosis AP?
Antibiotics + Percutaneous Drainage (?Surgery)
Infected pancreatic necrosis only indication for surgical intervention in the context of acute pancreatitis
high mortality if dead infected tissue is not debrided
Surgery involves necrosectomy (excision of necrotic tissue)
What is a Pancreatic pseudocyst?
peri-pancreatic fluid collection
↑ [pancreatic enzymes] within a fibrous capsule
presents >6 weeks after pancreatitis
95% spontaneously resolve over 6 months
require no intervention unless:
- Pseudocyst symptomatic (pain)
- Pseudocyst causing compression of surrounding structures e.g. CBD (obstructive jaundice), duodenum (high SBO)
- Pseudocyst infected (abscess)
These 3x situations pseudocyst → drained
How to manage pancreatic pseudocyst?
Percutaneously under radiological guidance (CT)
Endoscopically - EUS puncturing posterior wall of stomach & inserting stent
Surgically via laparoscopic/open:
pseudocystgastrostomy (cyst opened into stomach)
pseudocystjejunostomy
Describe the chronic pancreatitis inflammatory process?
Destroys endocrine & exocrine tissue → fibrosis of pancreas
Insulin-dependent diabetes mellitus & steatorrhea
Chronic pancreatitis management?
Surgical resection
Surgical drainage
Endoscopic
chronic pancreatitis effects?
Tissue atrophy
Ductal stenosis
Periductal fibrosis
Pain
Malabsorption
Weight loss
Diabetes mellitus
Pancreatic ascites
Thrombosis of portal and splenic vein
Obstructive jaundice
Diarrhea
Pseudocysts
