Dexamethasone for Nausea Does Not Raise Risk of Surgical-Site Infections

By Gene Emery

May 06, 2021

NEW YORK (Reuters Health) - Fears that dexamethasone may increase the risk of surgical-site infection when given to prevent nausea and vomiting after an operation appear to be unfounded.

A new noninferiority study of 8,725 volunteers who received the drug or placebo for their nonurgent, noncardiac surgery found an infection rate of 8.1% over 30 days with intravenous dexamethasone and 9.1% with placebo.

"Contrary to the concerns that have been previously expressed, for the moment, the key message is that dexamethasone is a very effective drug against nausea and vomiting, which is a very big problem, and we should probably be using it in more patients than we do already," chief author Dr. Tomas Corcoran told Reuters Health in a telephone interview.

"In particular it's safe in patients with diabetes and in patients with artificial implants such as knee and joint replacements," he said.

Dexamethasone's effects on the immune system are the reason why doctors have been concerned about its impact on post-surgical infection rates and the reason it isn't given more often.

Currently about half of patients who receive general anesthesia also get the drug, Dr. Corcoran and his colleagues note in their report in The New England Journal of Medicine.

"In reality, it's a drug we probably could give to more patients. Probably two-thirds should receive it," said Dr. Corcoran, director of research in the Department of Anaesthesia and Pain Medicine at Royal Perth Hospital in Australia.

In the pragmatic international trial, known as PADDI, dexamethasone therapy managed to trim the incidence of nausea and vomiting during the 24 hours after surgery, with a rate of 42% for patients getting the drug versus 54% among people getting intravenous placebo while under anesthesia and before the first incision (risk ratio, 0.78; 95% confidence interval, 0.75 to 0.82).

More importantly, when the team looked at infection rates, dexamethasone was noninferior to placebo.

The data were adjusted for diabetes status and people with poorly controlled diabetes were excluded.

"Our observation that the results in the subgroup of patients with diabetes mellitus were similar to those of the primary analysis is reassuring, since patients with diabetes are at a higher risk for complications related to infection and for hyperglycemia, and there is therefore reluctance to use dexamethasone in patients with diabetes," they said.

Among patients without diabetes, a hyperglycemic event occurred in 0.6% of dexamethasone volunteers and 0.2% of those who received placebo. The rates of insulin treatment were 0.5% and 0.1%, respectively.

Dexamethasone passed the noninferior test across a wide variety of other subgroups and the infection rates were lower regardless of gender, age, risk of infection, smoking status and surgical wound status.

One surprise in the study, said Dr. Corcoran, was the discovery that use of dexamethasone seemed to increase the risk of chronic pain by 1.6 percentage points at six months from surgery (8.7% vs. 7.1%; risk ratio, 1.23; 95% CI, 1.06 to 1.42).

"It's an incidental finding. It may be spurious. But nobody has looked at dexamethasone and chronic pain this far out," and it might be a reason for hesitation if the association turns out to be true, he said. "We need to clarify its effect on chronic pain."

Other data from the study revealed a trend for the infection risk to go down with increasing BMI, although everyone in the dexamethasone group was given the same 8 mg dose.

"The incidences of superficial, deep, or organ-space infections assessed individually were similar in the two groups," the researchers said.

SOURCE: The New England Journal of Medicine, online May 5, 2021.