AGA Institute Medical Position Statement on Acute Pancreatitis
2014-10-27 23:21 from： author：
The Medical Position Statements (MPS) developed under the aegis of the AGA Institute and its Clinical Practice and Economics Committee (CPEC) were approved by the AGA Institute Governing Board. The data used to formulate these recommendations are derived from the data available at the time of their creation and may be supplemented and updated as new information is assimilated. These recommendations are intended for adult patients, with the intent of suggesting preferred approaches to specific medical issues or problems. They are based upon the interpretation and assimilation of scientifically valid research, derived from a comprehensive review of published literature.1 Ideally, the intent is to provide evidence based upon prospective, randomized placebo-controlled trials; however, when this is not possible the use of experts’ consensus may occur. The recommendations are intended to apply to health care providers of all specialties. It is important to stress that these recommendations should not be construed as a standard of care. The AGA Institute stresses that the final decision regarding the care of the patient should be made by the physician with a focus on all aspects of the patient’s current medical situation.
Acute pancreatitis is a disease of increasing annual incidence and one that produces significant morbidity and mortality and consumes enormous health care resources. While many patients will recover from the attack with only general supportive care, about 1 in 5 will develop severe acute pancreatitis and 20% of these patients may die. The management of acute pancreatitis has evolved over several decades, and many treatments that were considered essential in the past have subsequently been abandoned based on more recent findings from clinical trials. Unfortunately, there are rather limited well-designed controlled clinical trials in this disease. This fact means that there remain today differences in opinion from center to center and country to country about the proper management of patients with acute pancreatitis. This has led in the past to several practice guidelines from various national and international professional societies that differ in their specific recommendations. These AGA Institute guidelines have been developed to guide clinicians in the management of patients with both mild and severe acute pancreatitis.
•The diagnosis of acute pancreatitis should be established within 48 hours of admission. The diagnosis should be based on compatible clinical features and elevations in amylase or lipase levels. Elevations in amylase or lipase levels greater than 3 times the upper limit of normal, in the absence of renal failure, are most consistent with acute pancreatitis. Elevations in amylase or lipase levels less than 3 times the upper limit of normal have low specificity for acute pancreatitis and hence are consistent with, but not diagnostic of, acute pancreatitis. Elevation of lipase levels is somewhat more specific and is thus preferred.
•Acute pancreatitis should be considered among the differential diagnoses in patients admitted with unexplained multiorgan failure or the systemic inflammatory response syndrome.
•Confirmation of the diagnosis, if required, is best achieved by computed tomography (CT) of the abdomen using intravenous contrast enhancement. Clinicians should be aware that an early CT (within 72 hours of illness onset) might underestimate the amount of pancreatic necrosis.
Assessment of Severity
•Clinicians should define severe disease by mortality or by the presence of organ failure and/or local pancreatic complications including pseudocyst, necrosis, or abscess. Multiorgan system failure and persistent or progressive organ failure are most closely predictive of mortality and are the most reliable markers of severe disease.
•The prediction of severe disease, before its onset, is best achieved by careful ongoing clinical assessment coupled with the use of a multiple factor scoring system and imaging studies. The Acute Physiology and Chronic Health Evaluation (APACHE) II system is preferred, utilizing a cutoff of ≥8. Those with predicted or actual severe disease, and those with other severe comorbid medical conditions, should be strongly considered for triage to an intensive care unit or intermediate medical care unit.
•Rapid-bolus contrast-enhanced CT should be performed after 72 hours of illness to assess the degree of pancreatic necrosis in patients with predicted severe disease (APACHE II score ≥8) and in those with evidence of organ failure during the initial 72 hours. CT should be used selectively based on clinical features in those patients not satisfying these criteria.
•Laboratory tests may be used as an adjunct to clinical judgment, multiple factor scoring systems, and CT to guide clinical triage decisions. A serum C-reactive protein level >150 mg/L at 48 hours after disease onset is preferred.
Determination of Etiology
•The etiology of acute pancreatitis should be able to be established in at least three fourths of patients. The initial history should particularly focus on previous symptoms or documentation of gallstones, alcohol use, history of hypertriglyceridemia or hypercalcemia, family history of pancreatic disease, prescription and nonprescription drug history, history of trauma, and the presence of concomitant autoimmune diseases.
•At admission, all patients should have serum obtained for measurement of amylase or lipase level, triglyceride level, calcium level, and liver chemistries (bilirubin, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase). If triglyceride levels cannot be obtained at admission, fasting triglyceride levels should be measured after recovery when the patient has resumed normal intake.
•Abdominal ultrasonography should be obtained at admission to look for cholelithiasis or choledocholithiasis. If the initial ultrasound examination is inadequate or if a suspicion of gallstone pancreatitis is still present, repeat ultrasonography after recovery should be performed. Endoscopic ultrasonography (EUS) can be used as an accurate alternative approach to screen for cholelithiasis and choledocholithiasis, either at admission or thereafter.
•CT or EUS should be performed in those patients with unexplained pancreatitis who are at risk for underlying pancreatic malignancy (age older than 40 years).
•Extensive or invasive evaluation is not recommended in those with a single episode of unexplained pancreatitis who are younger than 40 years of age. In those with recurrent episodes of pancreatitis, evaluation with EUS and/or endoscopic retrograde cholangiopancreatography (ERCP) should be considered. EUS is preferred as the initial test. If ERCP is undertaken in this setting, it should be performed by an endoscopist with the training, experience, and facilities to provide endoscopic therapy (including minor papilla sphincterotomy and pancreatic duct stent placement) and sphincter of Oddi manometry, if required. Genetic testing is not currently recommended as part of the initial workup but may be considered in selected patients.