Acute Necrotizing Pancreatitis 6t3f31

Acute Necrotizing Pancreatitis Intern: 周星賢 Date: 2003-5-26

Topics • What is acute necrotizing pancreatitis ? • The recognition of pancreatic necrosis • To manage with acute necrotizing pancreatitis

Review of acute pancreatitis • • • •

Presentations Causes: gallstones, alcohol abuse Severity: variable, mild, severe Severity classification: Ranson’ score, APACHE II

Causes of acute pancreatitis

Severity classification Ranson’s Score

APACH-II score

Classification of acute pancreatitis ~ from The International Symposium on Acute Pancreatitis, Arch Surg 1992 ~

• Acute pancreatitis • Severe acute pancreatitis • Mild acute pancreatitis • Acute necrotizing pancreatitis

Classification of acute pancreatitis ~ from The International Symposium on Acute Pancreatitis, Arch Surg 1992 ~

• Acute Pancreatitis: Definition – acute inflammation of pancreatitis, variable involvement of regional tissues or remote organ systems Pathology – interstitial edema, fat necrosis of parenchyma, pancreatic and peripancreatic necrosis and hemorrhage

• Severe Acute Pancreatitis Definition – organ failure, local complications (necrosis, abscess, pseudocyst) Pathology – a clinical presentation of pancreatic necrosis

Classification of acute pancreatitis ~ from The International Symposium on Acute Pancreatitis, Arch Surg 1992 ~

• Mild Acute Pancreatitis Definition – minimal organ dysfuntion, uneventful recovery, lacks the features of severe acute pancreatitis Pathology – microscopic interstitial edema

• Pancreatic Necrosis Definition – diffuse or focal area(s) of nonviable pancreatic parenchyma typically associated with peripancreatic fat necrosis Pathology – devitalized parenchyma, peripancreatic fat necrosis, hemorrhage, extensive interstitial fat necrosis with vessel damage an necrosis

Recognition of clinically severe acute pancreatitis ~ from The International Symposium on Acute Pancreatitis, Arch Surg 1992 ~

• Ranson’s score >= 3 • APACH II score >= 8 • Organ failure: Shock: systolic BP < 90 mmHg Pulmonary insufficiency: PaO2 <= 60 mmHg Renal insufficiency: Cre >= 2mg/dL after rehydration GI bleeding: >= 500 ml/24 hours

• Substantial pancreatic necrosis at least 30% glandular necrosis according to contrast-enhanced CT

Definition of Acute Necrotizing Pancreatitis •

Nonviable pancreatic parenchyma, Peripancreatic fat necrosis, Extensive interstitial fat necrosis, vessel damage

• Affect acinar cells, islet cells, and pancreatic ductal system • Increasing severity, morbidity and mortality • Importance of recognition for appropriate management

Recognition of Pancreatic Necrosis ~ Imaging and Intervention in Acute Pancreatitis, Radiology 1994 ~

• Clinical recognition of severe acute pancreatitis • Gold standard of diagnosis: Constrast-enhanced CT Criteria: nonenhanced pancreatic parenchyma >= 3cm or 30% area Mechanism: normal density 100~150 HU, necrosis <50 HU Semiquantitative measure: compare with spleen density

• Normal unenhanced pancrease (a) • Normal enhanced pancrease (b)

Statistical Results about Necrotizing Acute Pancreatitis ~ From NEJM 1999 ~

• Necrosis: 20 ~ 30% of acute pancreatitis • Mortality: sterile necrosis 10% infected necrosis 100% without surgery >15%, usually 20~40% with surgery

• Infected necrosis: 30~70% of necrotizing pancreatitis for more than 80% of deaths from acute pancreatitis

Management of acute necrotizing pancreatitis • Early management: Intensive medical care Prevention of infection with prophylactic antibiotics

• Late management Treatment of local infectious complications Aggressive debridement

Management of acute necrotizing pancreatitis • Prophylactic antibiotics ? • ER and Biliary sphincterotomy ? • Nutritional : TPN or Enteral feeding (jejunal feeding) ? • Surgical debridement (Necrosectomy) ?

Prophylactic Antibiotics • Prophylactic antibiotics in acute pancreatitis no significant benefit ( Ann Intern Med 1975, J Surg Res 1975)

• Prophylactic antibiotics in acute necrotizing pancreatitis?

Prophylactic antibiotics in acute necrotizing pancreatitis • Early antibiotics treatment in acute necrotizing pancreatitis ~ from Lancet 1995 ~ Design: 30 patients  cefuroxime (4.5 g/day, IV) 30 patients  no antibiotics Mortality rate: antibiotic group: 1/30 non-antibiotic group: 7/30

(p = 0.03)

Prophylactic antibiotics in acute necrotizing pancreatitis • The Role of Antibiotic Prophylaxis in Severe Acute Pancreatitis ~ from Arch Surg. 1997 ~ Retrospective, 180 patients with severe acute pancreatitis 3 periods: 50 p’t (1982~1989) no Abx, 55 p’t (1990~1992) non-protocol use, 75 p’t (1993~1996) with Abx (imipenem-cilastatin sodium) Results: Significant reduction in infection rate (P = 0.04) Only a trend toward improved survival (P = 0.11) 80% 70% 60% 50% 40%

Pan. Infection

30%

Mortality rate

20% 10% 0%

1982~89

1990~92

1993~96

ER and Endoscopic Sphincterotomy (ES) In acute pancreatitis due to gallstones •

Controlled trial of urgent ER and ES versus conservative treatment for acute pancreatitis due to gallstones ~ from The Lancet 1988 ~ 121 patients, acute pancreatitis, gallstones related, randomized control Results: improved outcome only with clinically severe pancreatitis

ER and Endoscopic Sphincterotomy (ES) In acute pancreatitis due to gallstones Early treatment of acute biliary pancreatitis by endoscopic papillotomy ~ from NEJM 1993 ~ • •

195 patients, acute pancreatitis, randomized control Results: Reduction in biliary sepsis (both mild and severe pancreatitis) No difference of local and

systemic complications Mortality rate: slightly lower (5 v.s 9 patients, P = 0.4)

Nutritional • The concept of “pancreatic rest” and TPN Not improving outcome or further benefit except decreasing pain Disadvantages: complications, high cost (Clinical nutrition in pancreatitis

from Dig Dis Sci 1997)

Nutritional • TPN v.s EF (enteral feeding) from Br J Surg 1997 38 patients, randomized into EF group (n=18) and TPN group ( n=20) Results: EF well tolerated, without adverse effects, fewer complications (p< 0.05), 1/3 the cost of TPN

Nutritional • TPN v.s TEN (total enteral nutrition) Compared with parenteral nutrition, enteral feeding attenuated the acute phase response and improved disease severity in acute pancreatitis ~from Gut 1998~ Methods: 34 patients, randomized to TPN or TEN group Results: SIRS, sepsis, organ failure, and ITU were improved in TEN group The CRP and disease severity scores significantly improved

Nutritional

Surgical debridement Who? When? and How? • Acute necrotizing pancreatitis: sterile v.s infected Infected ANP: Uniformly fatal without intervention(100%), Necrosectomy soon after confirmation of infected necrosis

Sterile ANP: Mortality 10%, benefit of surgery remain unproved, Frequently indicated for surgical debridement

Surgical debridement Who? When? and How?

Diagnosis of infected necrosis: CT-guided fine-needle aspiration: safe, Sensitivity 96%, Specificity 99%

Surgical debridement Who? When? and How? CT-guided fine-needle aspiration

Surgical debridement • Surgical treatment modalities for infected necrosis Surgical Treatment of Infected Necrosis

~ from World J. Surg. 1997 ~

Surgical debridement • Mortality among patients with infected necrosis Surgical Treatment of Infected Necrosis

~ from World J. Surg. 1997 ~

Conclusions • Pancreatic necrosis is being increasingly recognized (due to physicians’ awareness, improved radiologic imaging)

• Importance of identification of pancreatic necrosis: high morbidity and mortality

• Diagnosis of pancreatic necrosis: Constrast-enhanced CT • Aggressive medical care with prophylactic antibiotics

Conclusions • ER with sphincterotomy in severe acute gallstone pancreatitis with biliary obstruction (hyperbilirubinemia, cholangitis)

• Enteral feeding superior than TPN • Surgery with necrosectomy with drainage in patients with infected necrosis