|Video: Acute Pancreatitis Overview|
Overview Acute pancreatitis is a relatively common condition presenting with severe, acute, constant epigastric pain. Incidence of ~5 per 100,000/year. Acute pancreatitis has a significant mortality. Early complications include acute renal failure, DIC, hypocalcemia and ARDS.
Acute Pancreatitis: An inflammatory process in which pancreatic enzymes are activated and cause autodigestion of the gland.
Chronic Pancreatitis: Irreversible damage causing fibrosis and scarring to the pancreas, resulting in exocrine and endocrine dysfunction
Pancreatic pseudocyst: Cystic space within the pancreas not lined by epithelial cells, often associated with chronic pancreatitis.
Pancreas Anatomy and Physiology
Pancreatic anatomy Pancreas extends retroperitoneally across posterior abdominal wall. It means “All (pan) Flesh (Kreas)”. The pancreas consists of the following parts:
The head is encircled by duodenum and tail in contact with spleen. Pancreas has a poorly developed capsule & therefore adjacent structures (common bile duct, duodenum, splenic vein, transverse colon) are commonly involved in inflammatory process.
- Pancreatic branches of the splenic artery
- Superior pancreaticoduodenal artery
- Inferior pancreaticoduodenal artery
- Drains with the splenic vein → Superior Mesenteric → Portal vein
- Parasympathetic → Vagus nerve → Stimulates pancreatic juice secretion
- Head and Neck → Pancreticoduodenal nodes →
- Body and Tail → Pancreaticosplenic nodes →
- Fusion of the ventral and doral outpounchings of forgut
Pancreatic physiology exocrine (98%) & endocrine (2%) functions
Exocrine: Pancreatic acinar cells produce digestive enzymes, which are stored in secretory granules. The Pancreatic exocrine secretion is regulated by cephalic, gastric & intestinal stimuli. Acinar cells secrete pancreatic juice made up the enzymes:
- Amylase → Carbohydrate digestion
- Lipase → Lipid digestion after bile has emulsified the fat
- Proteases (MANY!) → Protein digestion
Exocrine section is stimulated by:
- Vagus nerve
- Secretin (hormone)
Endocrine: Islets of Langerhans – clusters of hormone-producing cells secreted directly into circulation. Endocrine cells of the pancreas:
- Beta cells → Insulin
- Alpha cells → Glucagon
- D cells → Somatostatin.
|Cells of the Pancreas||Secretion||Function|
|Acinar cells secrete enzymes
into the duodenum
|Islets of Lagerhan secrete hormones
into the bloodstream
|Glucagon||Stimulates glucose release into the bloodstream from glucose stores|
|Insulin||Increases cell uptake and storage of glucose|
|Endoscopic retrograde cholangiopancreatography|
Signs and Symptoms
|Remember Amylase is not specific to the pancreas. It can be elevated in gastrointestinal ischemia with infarction or perforation, vomiting associated with pancreatitis can cause elevated amylase of salivary origin. Elevated serum lipase level is more specific than is amylase to pancreatic origin and remains elevated longer than does amylase|
Diagnosis Should be suspected in a patient with acute onset of a persistent, severe, epigastric pain with tenderness on palpation. Requires the presence of 2 of the following 3 criteria:
- Acute onset of persistent, severe, epigastric pain often radiating to the back.
- Elevation in serum lipase or amylase to 3 times or greater than the upper limit of normal.
- Characteristic findings of AP on imaging (CT, MRI, transabdominal ultrasound).
Glasgow Imrie criteria (PANCREAS)
- PaO2 <8kPa
- Age >55y – Poorer Prognosis
- Neutrophils/WCC >15000
- Corrected Calcium – Increased protease in serum chelates serum calcium
- Raised blood urea – Increased protease in serum leads to increase in protein breakdown leading to ureamia
- Elevated Enzymes – LFT dysfunction (specifically in gall stone causes)
- Albumin – Increased protease leads to albumin breakdown and shift of albumin to interstitium cause of increased in permeabiliy.
- Sugar, blood glucose >10mmol/L – beta cell damage
Grades of severity
- Mild acute pancreatitis
- No organ failure
- No local or systemic complications
- Moderately severe acute pancreatitis
- Organ failure that resolves within 48 h (transient organ failure) and/or
- Local or systemic complications without persistent organ failure
- Severe acute pancreatitis
- Persistent organ failure (>48 h)
- Single organ failure
- Multiple organ failure
- Persistent organ failure (>48 h)
Difference between acute pancreatitis and chronic pancreatitis
Treatment of pancreatitis is mainly supportive and includes “pancreatic rest”. Withholding food or liquids by mouth until symptoms subside, and adequate narcotic analgesia, usually with meperidine.
Continuous pancreatic inflammation may develop into full blown MODS or SIRS.
Signs of systemic inflammatory response syndrome (SIRS)
SIRS—defined by presence of two or more criteria:
- Heart rate >90 beats/min
- Core temperature <36°C or >38°C
- White blood count <4000 or >12000/mm3
- Respirations >20/min or PCO2 <32 mm Hg
Prognosis Mortality is associated with pancreatic necrosis and the presence of sepsis.
Difference between acute and chronic pancreatitis