Approximately two-thirds of patients with necrotizing pancreatitis can be managed conservatively, and the mortality rate will remain relatively low, Dr. Hjalmar C. van Santvoort and his colleagues reported in Gastroenterology (2011;141:1254-63).
Even in patients who develop infected necrosis, delaying intervention as long as possible and using an approach that begins with simple percutaneous catheter drainage before attempting more invasive procedures will allow resolution in approximately 30% of patients, said Dr. van Santvoort of the department of surgery at University Medical Center Utrecht (the Netherlands) and his associates in the Dutch Pancreatitis Study Group.
Treatment of necrotizing pancreatitis has changed considerably in recent years, but studies of patient outcomes have not kept pace with those changes. Most of the recent studies have been small and retrospective, and most of their data comes from highly experienced, single centers. "It is questionable whether these results can be extrapolated to daily practice in nonexpert centers," the investigators said.
So they performed a prospective 4-year study in a nationwide Dutch cohort of 639 patients "covering the entire spectrum of necrotizing pancreatitis in recent years."
All patients received immediate rigorous fluid resuscitation and underwent full laboratory assessments within the first 3 days of hospitalization. Nasojejunal enteral feeding was initiated for those who couldn’t tolerate an oral diet, and parenteral nutrition was only initiated if the enteral route was not tolerated or provided insufficient nutrition.
Antibiotics were given only if infection was suspected or documented. And patients who appeared to be developing organ failure were treated in an ICU.
Further intervention was only undertaken if infection of pancreatic or peripancreatic necrosis was suspected or verified. "Whenever possible, intervention was postponed until approximately 4 weeks after the onset of the disease."
The preferred first intervention was percutaneous catheter drainage, or endoscopic transluminal catheter drainage. If that was unsuccessful, minimally invasive video-assisted retroperitoneal debridement or endoscopic transluminal necrosectomy were considered safe and feasible.
Open necrosectomy by laparotomy with continuous postoperative lavage was considered as a last resort, for extreme clinical deterioration thought to be caused by abdominal compartment syndrome, bowel ischemia, or perforation of a visceral organ.
The primary outcome of the study was mortality during hospitalization.
Approximately two-thirds of patients (62%) were treated with a conservative approach, without any radiologic, endoscopic, or surgical intervention. Mortality in this group was only 7%. Moreover, this group included 11 patients with infected necrosis who received only IV antibiotics "because of their extraordinary good clinical condition in the absence of sepsis or organ failure." Their mortality was 0%.
In contrast, mortality in the remaining one-third of patients who required an invasive procedure as their first intervention was 27%. However, the longer the interval was between admission and use of an invasive intervention, the lower the mortality. Mortality was 56% in patients who underwent invasive intervention at 0-14 days, 26% if the intervention was delayed until 14-29 days, and 15% if it was delayed until 29 days or more.
This linear association remained robust when the data were adjusted to account for baseline prognostic factors such as patient age, APACHE score, the severity of CT findings, and the presence or absence of organ failure.
Also among the 33% of patients who required a radiologic, endoscopic, or surgical intervention for infected necrosis, at a median of 28 days, the longer the interval before such intervention, the lower the risk of complications such as new-onset organ failure, intra-abdominal bleeding, and enterocutaneous fistula or perforation of a visceral organ. The risk of complications was 72% if the intervention was done at 0-14 days, 57% if it was delayed 14-29 days, and 39% if it was delayed 29 days or more.
In all, 5% of patients required emergency laparotomy, usually within 5 days of admission. Mortality was 78% in these patients. The deaths occurred almost exclusively in patients who had organ failure (35%), compared with those who did not have organ failure (2%).
"We confirmed that approximately half of the patients with necrotizing pancreatitis who die have sterile necrosis. Mortality in these patients is almost exclusively caused by multiple organ failure in the first week. There currently is no effective treatment to improve outcome in these patients," Dr. van Santvoort and his associates said.
"This supports the theory that organ failure early in the course of acute pancreatitis, which is associated with systemic release of cytokines and a systemic inflammatory response syndrome, is a different clinical entity than organ failure as a result of sepsis from infected necrosis at a later stage," they noted.