By Lorraine L. Janeczko                     January 08, 2015

NEW YORK (Reuters Health) - Active negative-pressure peritoneal therapy with the ABThera (Kinetic Concepts Inc) temporary abdominal closure device may reduce systemic inflammation after abbreviated laparotomy, new research from Canada suggests.

"Surgeons should be utilizing negative pressure wound therapy. They should use this philosophy, but not any one technology. This recommendation is consistent with the best clinical-derived practice guidelines of the World Society of the Abdominal Compartment Syndrome," said lead study author Dr. Andrew W. Kirkpatrick of the University of Calgary and the Foothills Medical Center in Calgary, Alberta, Canada, by phone with Reuters Health. (Those guidelines are here:

"I don't think this has been a definitive study for any particular device or manufacturer, but I do think that this is an exciting treatment philosophy that may be getting right to the very initiating cascades of sepsis, septic shock, multi-system organ failure, and I look forward to us doing further work with these techniques," he said.

"There is a signal that enhanced peritoneal suction appears to benefit the most ill and injured patients, though we have much to learn. I think this is a starting point in study as opposed to a finished conclusion," he added.

In their single-center study, Dr. Kirkpatrick and colleagues randomized 45 adults with abdominal injury (46.7%) or intra-abdominal sepsis (52.3%) to treatment with either the ABThera or Barker's vacuum pack.

As reported online December 22 in Annals of Surgery, at 48 hours after randomization the ABThera patients had significantly less peritoneal fluid drainage. But plasma concentrations of IL-6 showed no between-group differences at 24 or 48 hours.

Nor were there any significant differences in plasma concentrations of IL-1 beta, IL-8, IL-10, or IL-12 p70 or tumor necrosis factor alpha between these time points. The cumulative incidence of primary fascial closure at 90 days was similar between the groups, but the 90-day mortality was improved in the ABThera group (hazard ratio, 0.32; p=0.04).

The authors cautioned, though, that their findings might be due to type 1 error and they advised that "further work is required to explain the potential mechanisms of improved outcomes and confirm our findings before they are used to inform surgical practice."

"There was a survival difference but we still don't exactly know why," Dr. Kirkpatrick said in an interview. "Figuring out why hopefully will lead to more fundamental understanding of intra-abdominal sepsis and trauma and the mechanisms of inflammation."

"We're still learning so much about how to manage the open abdomen. The acidic fluid that we often thought was benign is really a sea of inflammatory mediators," he added.

Coauthor Dr. Derek J. Roberts, also of the University of Calgary and the Foothills Medical Centre, Calgary, wrote in an email, "We observed improved survival with use of a device that has been suggested to afford more active or improved negative pressure to the peritoneal cavity, but we could not confirm that this better drained the cavity, aided in closing the abdomen, or removed mediators from the peritoneum or blood better than the other device. Thus, it has to be confirmed by future, larger studies before being used to inform practice."

This study was partially funded by Kinetic Concepts Incorporated, the manufacturer of the ABThera.