Acute Pancreatitis

1. Acute Pancreatitis Ashley Duckett, MD Theresa Cuoco, MD, FACP

2. Objectives • Identify clinical presentation and etiologies of acute pancreatitis • Recognize the importance of severity of pancreatitis in determining management and outcomes • Understand the indications for imaging and antibiotics in acute pancreatitis

3. Key Messages • Early aggressive hydration is critical in the management of acute pancreatitis. • Imaging with contrasted CT or MRI is indicated at 48-72 hours in patients with severe disease. • Early enteral nutrition improves outcomes in patients with severe pancreatitis. • Severity scores can be used to triage patients at risk for complications.

4. Clinical presentation • Abdominal pain, distention • Nausea/vomiting (90%) • Fever, tachycardia, shock, coma • Dyspnea (pleural effusion) • Shallow respirations (diaphragmatic irritation) • Jaundice • Grey-Turner’s/Cullen’s 1% - intraabdominal hemorrhage

5. Etiologies • Gallstones- 35-40% (increased ALT >150 is 50% sensitive and 96% specific) *women • Alcohol – 30% *men • Hypertriglyceridemia • Hypercalcemia • Post-ERCP -3% of diagnostic, 25% if SOD studies • Drugs – direct toxic, immunologic, ischemic causes – cocaine, HCTZ • Genetic mutations • Trauma • Infection – Viruses (mumps, hep B, CMV, HIV), Bacteria (mycoplasma, legionella, salmonella), fungi, parasites • Idiopathic -15-20% • Autoimmune (although usually presents mimicking neoplasm) • Scorpion bite • SOD dysfunction? Pancreatic divisum?

6. Pathophysiology • Activation of trypsin in acinar cells • Activating multiple pancreatic digestive enzymes (synthesized but not secreted) • Leak into interstitial space and systemic circulation • Intrapancreatic Inflammation • Mediated by cytokines/inflammatory markers • SIRS • Extrapancreatic Inflammation • ARDS • Multiple organ failure (MOF) • Respiratory, cardiovascular, renal

7. Diagnosis • Requires 2 of the following 3 features • Characteristic abdominal pain • Epigastric, band-like radiating to back, assoc n/v • Amylase and/or lipase >/= 3 times the upper limit • Amylase rises in 6-12 hrs, elevated 3-5 days • Lipase sensitivity 85-100%; more specific than amylase • Characteristic CECT (contrast enhanced CT) findings (or MRI/US) • Edema, peripancreatic fat stranding, necrosis, calcifications, pancreatic heterogeneity

8. Imaging • Plain XR – unremarkable or have “sentinel loop” (localized ileus) or “colon cutoff sign” in severe disease • CXR – pleural effusion suggests increased risk of complications • Abd ultrasound: diffuse, hypoechoic pancreas, useful for gallstones, not good for necrosis • CT scan – useful for complications and for severity assessment • When to CT? indicated if need to assess for necrosis (severe disease) at 48-72 hours • Oral and IV contrast preferred (to diagnose necrosis, calcifications, stones, mass) • MRCP – best for delineating fluid collections, necrosis, ducts, looking for choledocholithiasis

9. Management • Determine etiology – history, LFTs, TGs, calcium, abdominal ultrasound for stones • Determine severity and send severe to ICU • FLUIDS FLUIDSFLUIDS – Initial bolus, then 250-300cc/hr x 48 hours if cardiac fx normal • Increasing BUN at 24 hrs predicts mortality • Monitor glucose and lytes (Ca, Mg) • No daily amylase/lipase; no correlation with severity • Pain management • Nutrition – start oral feeds when pain improving, no ileus in mild dz

10. Nutrition • Need for nutrition and pancreatic rest in severe pancreatitis or anyone NPO > 5 days • Early enteral nutrition (at 24-48 hrs) reduces mortality, multi-system organ failure, infections and need for operative interventions compared to TPN • Maintains intestinal barrier, prevents translocation • High protein, low fat formula

11. Antibiotics • ACG – prophylactic antibiotics not recommended • AGA – abx should be restricted to pts with >30% pancreatic necrosis by CT and should be used for less than 14 days • Meropenem or imipenem are drugs of choice • CT guided aspiration/culture recommended if infected pancreatic necrosis is suspected (fevers, sepsis, increasing WBC)

12. Classification of Acute Pancreatitis • Interstitial edematous • Acute inflammation of pancreatic parenchyma and peripancreatic tissue • Necrotizing Acute Pancreatitis • 5-10% of patients • Pancreatic or peripancreatic necrosis • Appears as non-enhancing area • Early CECT may underestimate (wait 48-72h)

13. Severity of Pancreatitis • Mild Acute • No organ failure, local or systemic complications • Moderately Severe • Transient organ failure (OF) <48h • Local or systemic complications w/o persistent OF • Severe Acute • Persistent organ failure (>48h) • Mortality ~36-50%; higher w infected necrosis

14. Severity scores • Most cases mild, 15-25% severe • Depends on presence and duration of organ failure • Early risk stratification (median time to ICU transfer is 24 hours after admission) • APACHE II most widely used – score >8=severe • BISAP – simple, can be done early • BUN, AMS, SIRS, Age>60, pleural effusion • >3 points indicates increased risk of death • Ranson’s criteria

15. Ranson’s Criteria At admission At 48 hrs out Ca < 8 HCT fall > 10% PO2 < 60 BUN increase > 5 Base deficit > 4 mEq/L Sequestration of fluids > 6L • Age > 55 • WBC > 16 • Glu > 200 • AST > 250 • LDH > 350

16. Complications • Pancreatic necrosis – becomes infected in about 30%; usually monomicrobial (Ecoli, Pseudomonas, Kleb) • Abscesses • Pseudocysts -Drainage prior to maturation (6 wks) can lead to complications • Splenic vein thrombosis (up to 19% of pts) • Anticoagulation may be needed for complications • Abdominal compartment syndrome • ARDS, shock, renal failure, GI bleeding

17. Definitions of Pancreatic and Peripancreatic Fluid Collections • APFC: Acute Peripancreatic Fluid Collection • Assoc w intersitialpanc; no necrosis • Homogenous; no definable wall; adjac to pancreas • Pancreatic Pseudocyst • Well circumscribed, homogenous, with wall • Maturation usually >4 weeks after acute panc • ANC: Acute Necrotic Collection • Only in setting of necrotizing panc • Heterogenous, no wall, intra and/or extra pancreatic • WON: Walled Off Necrosis • Heterogenous, well defined wall, intra/extra • Maturation >4 weeks after acute necrotizing panc

18. Gallstone pancreatitis – early ERCP or surgery? • Early ERCP or surgery to remove bile duct stones may decrease severity of pancreatitis • ERCP within 72 hours in pts with cholangitis OR concern for stone (stone on imaging, dilated CBD, jaundice, rising LFTs) • All patients with gallstone panc should have cholecystectomy • 25-30% risk of recurrent panc, cholecystitis or cholangitis in <18 wks • Recent retrospective of mild gallstone panc who had lap chole within 48 hrs of admission • No increase in morbidity or mortality • Decreased hospital stay and ERCP • Consider early consult in appropriate patients

19. References • Banks P et al. Practice Guidelines in Acute Pancreatitis. Am J Gastroenterol 2006; 101:2379-2400 • Banks P et al. Classification of acute pancreatitis-2012:revision of the Atlanta classification and definitions by international consensus. Gut 2013; 62: 102-111. • Al-Omran M et al. Enteral versus Parenteral Nutrition for Acute Pancreatitis (Review). Cochrane Database of Systematic Reviews 2010, Issue1 • Falor et al. Early Laparoscopic Cholecystectomy for Mild Gallstone Pancreatitis. Arch Surg 147: Nov 2012 • Van Santvoort et al. Early Endoscopic Retrograde Cholangiopancreatography in Predicted Severe Acute Biliary Pancreatitis: A Prospective Multicenter Study. Annals of Surgery. 250 (1); July 2009 • Wu, Bechien. Prognosis in Acute Pancreatitis. CMAJ: 183 (6); April 2011