LETHAL FACTORS AND RESPONSE TO THERAPY IN EXPERIMENTAL BILE-REFLUX PANCREATITIS

Surgical management of necrotizing pancreatitis

The most important diagnostic step in the management of patients with severe acute pancreatitis is the discrimination between acute interstitial and necrotizing pancreatitis. Measurement of C-reactive protein, lactic acid dehydrogenase, alpha-1-antitrypsin, and alpha-2-macroglobulin and contrast-enhanced CT are useful in detecting the necrotizing course of acute pancreatitis. C-reactive protein, lactic acid dehydrogenase, and contrast-enhanced CT offer detection rates of 85 per cent to more than 90 per cent for pancreatic necrosis. Surgical decision-making in necrotizing pancreatitis should be based on clinical, morphologic, and bacteriologic data. Patients with focal pancreatic necrosis, in general, respond well to medical treatment and do not need surgery. Extended (50 per cent or more) pancreatic necroses, infected necroses, and intrapancreatic parenchymal necroses plus extrapancreatic fatty tissue necroses are indicators for surgical management. The decision for the timing of operation in patients with proved necrotizing pancreatitis should be based on clinical criteria: the development of an acute surgical abdomen, generalized sepsis, shock, persisting or increasing organ dysfunction, or some combination thereof despite maximum intensive care treatment for at least 3 days. Major pancreatic resection for the treatment of necrotizing pancreatitis appears disadvantageous. Necrosectomy and continuous local lavage allow debridement of devitalized tissue and preservation of vital pancreatic tissue. Postoperative local lavage thus results in an atraumatic evacuation of necrotic tissue, the bacterial material, and biologically active substances. The hospital mortality rate of patients treated with necrosectomy and continuous local lavage (the Ulm protocol) is below 10 per cent. Nevertheless, controlled prospective clinical trials should be performed in order to bring more precision to our clinical decisions in respect to the role of surgery for this disease.

Treatment of acute pancreatitis. Comparison of animal and human studies

In this review, we compared the outcome of 25 studies of experimentally induced pancreatitis in animals with 13 studies of human acute pancreatitis in which the same therapeutic agents were used (aprotinin, glucagon, 5-fluorouracil, somatostatin, peritoneal lavage). Whereas 81% of the animal studies had a positive outcome (improvement in survival), only 7.7% of the human studies showed a positive outcome on survival. Most animal studies suffered from a protocol in which treatment was not significantly delayed after induction of acute pancreatitis. Of the 12 human studies that showed no effect of treatment on survival, none had sufficient statistical power (1 - beta error) for the investigators to have confidence in the negative outcomes. This was due to the fact that the studies had too few patients or that the event rates in the untreated populations were too low. Only five of the human studies reported the complication rates of acute pancreatitis in patients who did not die of their disease. Treatment (by any agent) did not improve the complication rate in these studies, but only one of the five reports had sufficient statistical power for the investigators to have confidence in these negative results. Large multicenter studies with sufficient numbers of patients with severe pancreatitis (high mortality and complication rates) are needed to evaluate new therapies in this disease.

Ampicillin concentrations in pancreatic fluid bile obtained at endoscopic retrograde cholangiopancreatography (ERCP)

To investigate the distribution of ampicillin to the pancreas, ampicillin concentrations in pancreatic fluid obtained at endoscopic retrograde cholangiopancreatography (ERCP) were determined. Alternatively, ampicillin concentrations in bile obtained via ERCP were determined. Ten subjects with non-acute biliary-tract or pancreatic disease received a single dose of ampicillin (250 or 500 mg) parentally before ERCP. Timed simultaneous specimens of blood and pancreatic fluid or bile were obtained. Serum concentrations of ampicillin were measured in all subjects. In six of seven subjects no ampicillin was detectable in pancreatic fluid; in the seventh less than 1 microgram/ml was found. Pancreatic duct anatomy did not appear to correlate with pancreatic fluid concentrations. Failure to detect ampicillin in pancreatic fluid may account for results of clinical studies in which no clinical benefit from ampicillin has been found. Low or undetectable concentrations of ampicillin were found in bile; these concentrations in bile obtained at ERCP are similar to those found previously in bile recovered at biliary-tract surgery.