Immunosuppression doesn't increase infection risk after open ventral hernia repair

Last Updated: 2018-08-07

By Lorraine L. Janeczko

NEW YORK (Reuters Health) - Immunosuppressed patients having open ventral hernia repair are at increased risk for surgical-site occurrence 30 days later, but not for wound infections, the need for another procedure, or other complications, a new study suggests.

The findings support "the notion that immunosuppressant medications can be maintained safely during elective ventral hernia repair with mesh," Dr. David M. Krpata of the Cleveland Clinic Foundation in Cleveland, Ohio, told Reuters Health by email.

"We are able to control for type and positioning of mesh used, other comorbidities, etc., when trying to determine the overall effect of immunosuppression," added co-author Dr. Ajita S. Prabhu, also of the Cleveland Clinic Foundation, by email. "And what we are seeing is that it doesn't seem to make a huge difference in wound outcomes, other than an increased rate of seromas that did not require intervention."

Drs. Krpata and Prabhu and their colleagues used the database of the Americas Hernia Society Quality Collaborative (AHSQC) to identify all patients undergoing the elective surgery in the U.S. over almost four years. The team compared the incidence of 30-day wound events in patients on immunosuppressants during the three months before surgery and patients not on such agents.

Of the more than 3,500 patients included in the study, 1,200 patients remained for analysis after propensity matching. Of these, 1,000 (83.3%) were not, on immunosuppression and 200 (16.7%) were on immunosuppression.

The researchers found no significant differences between the two groups in the incidence of 30-day surgical-site infection, surgical-site occurrence requiring additional surgery, or other 30-day morbidity or mortality outcomes.

But patients on immunosuppressants had a higher likelihood of surgical-site occurrences (15.0% vs. 9.6%, P=0.03), the team reports in Surgery, online July 18; 40% of the immunosuppressed group had seroma, the most common surgical-site occurrence, compared to 35% of the control group.

"Immunosuppression has long been considered to negatively impact wound healing. As such, some consider it a relative contraindication to elective surgery," Dr. Krpata explained.

"Recently more consideration has been given to continuing immunosuppressants throughout surgery, as stopping them may have a greater negative impact on the indication for the immunosuppression (i.e., autoimmune disease)," he added.

"This article is a good start at looking at this topic," Dr. Prabhu noted. "It is the first of its kind to be able to look at wound outcomes in immunosuppressed patients undergoing hernia repair using hernia-specific data."

"While it is a long-held belief that immunosuppression is a risk factor for postoperative morbidity, there hasn't been a great way to look at that prior to now," she explained. "The AHSQC has provided a wealth of information through the collection of granular hernia-specific data using standardized definitions surrounding wound events and wound outcomes after surgery."

Dr. Prabhu acknowledged limitations to the study, including that it was underpowered to determine the difference between steroids and other forms of immunosuppression, such as chemotherapy.

"However, I suspect we will be able to look at that in the future as further data are entered," she said. "Also, we still don't know the long-term implications of having a seroma."

SOURCE: https://bit.ly/2niyYpD

Surgery 2018.