乌鸦传媒

Negative pressure wound therapy did not reduce surgical site infections among obese patients who had cesarean section deliveries, a large randomized trial indicated.

Infection rates were 3.6% among 816 participants receiving the prophylactic treatment and 3.4% in an 808-patient control group receiving with standard wound dressings, reported Methodius Tuuli, MD, MPH, of the Indiana University School of Medicine in Indianapolis, and colleagues.

Incidence of adverse skin reactions such as blisters, bleeding, and erythema was also higher with negative pressure therapy (7% vs 0.6%), prompting the researchers to halt the trial early, the group wrote in .

"Routine use of prophylactic negative pressure wound therapy in obese women after cesarean is not justified," Tuuli said in an email. "Rather, consistent use of simpler and cheaper evidence-based interventions can achieve low rates of infection after cesarean in this high risk population."

Loralei Thornburg, MD, a maternal-fetal medicine specialist at the University of Rochester Medical Center, who was not involved in the study, said it was significant to see data from a large, racially diverse clinical trial that showed no benefits of negative pressure treatment -- a therapeutic that adds substantial costs to C-section procedures.

"The preliminary data really says that in a cost-benefit ratio, this probably isn't where we want to put our efforts in reducing surgical site infection," Thornburg told 乌鸦传媒.

Risk of surgical site infection after C-section has been reduced primarily by evidence-based bundles used in hospitals across the country, Thornburg added. This includes procedures like closing the extra thickness around the incision with additional sutures instead of staples, alcohol-based surgical preparations, and using a variety of antibiotics -- especially in cases when there are ruptured membranes.

Negative pressure wound therapy, which uses a battery-powered, peel-and-place device to extract fluids from a surgical wound site, has become more frequently used after C-sections in recent years. The treatment can add between $200 and $500 to the cost of a delivery, Tuuli and colleagues stated.

A recent study from Denmark, conducted in nearly all white women, showed a , study authors noted. In contrast, over half of the patients in the new trial were Black. Because African Americans are at the highest risk of poor pregnancy outcomes in this country, Thornburg said, the trial was more likely to determine whether the intervention would be beneficial to the U.S. population.

The trial was conducted from February 2017 to November 2019 at four academic centers and two community facilities. Patients with BMI values of 30 or more who underwent either planned or unplanned C-section delivery were eligible for the trial.

Trial participants were randomized to either prophylactic negative pressure wound therapy using the Prevena device or standard wound dressing. Before delivery, all participants received infection prevention procedures, such as preoperative antibiotics, skin preparation, closure of the subcutaneous layer if the depth was 2 cm or greater, and skin closure with a subcutaneous suture.

Women were monitored until hospital discharge and then again at 30 days after surgery for signs of infection or wound complications. The researchers also obtained medical records from postpartum visits, and collected information on patient demographics, including race and ethnicity, as cesarean delivery may lead to more postoperative complication rates among Black women.

No patients were lost to follow and nearly all received their assigned intervention. In the negative pressure group, the median duration of the intervention was 4 days.

In the negative pressure group, 29 participants received a diagnosis for superficial or deep surgical-site infection, compared with 27 in the standard wound dressing cohort.

There was no difference in risk of wound complications, including superficial or deep infections, as well as organ space infections. There was also no difference in the rate of serious adverse events, such as maternal death, sepsis, admission to intensive care, necrotizing fasciitis, and postpartum hysterectomy.

Tuuli and colleagues recognized that the risk of surgical site infection was lower than the 10% risk reported in other studies, possibly due to the risk of evidence-based implementations to reduce infection risk. As well, the trial was limited by the inability to blind investigators, and also because it was stopped early and therefore may be underpowered.

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