Dexamethasone reduces postoperative nausea, vomiting in GI surgery
A single dose of 8 mg intravenous dexamethasone at induction of anaesthesia lessens both the episodes of postoperative nausea and vomiting (PONV) at 24 hours and the need for rescue antiemetics for up to 72 hours in patients undergoing bowel surgery, according to a recent study. In addition, there is no significant increase in adverse events in these patients.
“[W]e have shown, for the first time, that a single 8 mg dose of intravenous dexamethasone at induction significantly reduces the incidence of PONV, reduces the need for rescue antiemetics and increases the speed of return to diet after surgery,” researchers said. “Furthermore, we showed dexamethasone to be safe in these patients, with no increase in adverse events.”
A total of 1,350 participants (aged ≥18 years) in 45 UK hospitals were recruited and randomized to additional dexamethasone (n=674) or standard care (n=676) at induction of anaesthesia.
Vomiting within 24 hours of surgery occurred in 395 patients, with 172 (25.5 percent) in the dexamethasone arm and 223 (33.0 percent) in the standard care arm (number needed to treat [NNT], 13; 95 percent CI, 5 to 22; p=0.003). [BMJ 2017;357:j1455]
The strongest factors associated with PONV were female sex, history of PONV, nonuse of tobacco, younger age, volatile anaesthetics, duration of anaesthesia and postoperative opioid use, according to a systematic review of 22 large studies identifying predictors of PONV. [Br J Anaesth 2012;357:742-53]
“These factors were equally balanced between both arms of this trial, and we saw no evidence of differences in the relative reduction of vomiting according to these predictors,” researchers said. “While maintenance with propofol is known to reduce PONV, only 93 patients (7 percent) in the trial received it.”
Additional postoperative antiemetics were used less by participants who received dexamethasone for up to 3 days after surgery. In the first 24 hours after surgery, antiemetics were given on demand to 265 (39.3 percent) patients in the dexamethasone arm and 351 (51.9 percent) in the standard care arm (NNT, 8; 5 to 11; p<0.001). The decrease in on-demand antiemetics remained up to 72 hours.
There were no significant between-group differences in the targeted adverse events. A total of 147 infection episodes were reported among 136 patients within 30 days, of which 69 (10.2 percent) were in the dexamethasone arm and 67 (9.9 percent) in the control arm (risk ratio [RR], 1.03; 0.75 to 1.42; p=0.84).
These episodes involved 84 patients with superficial wound infections (6.4 vs 6.1 percent; RR, 1.05; 0.70 to 1.59; p=0.81), 19 with urinary tract infections (1.6 vs 1.2 percent; RR, 1.38; 0.56 to 3.41; p=0.48) and 22 with respiratory infections (1.0 vs 2.2 percent; RR, 0.47; 0.19 to 1.14; p=0.09).
These findings strongly support the use of dexamethasone as an induction antiemetic for patients undergoing bowel surgery, according to researchers.
Current guidelines on the management and prevention of PONV are complex and not widely adopted. [Anesth Analg 2014;357:85-113; Anesth Analg 2007;357:1615-28]
“Our trial of patients undergoing small and large bowel surgery provides a simple solution for a reduction in PONV,” researchers said.
“We have shown that addition of a single intravenous 8 mg dose of dexamethasone significantly reduces PONV at 24 hours, is safe to use, and should be incorporated into routine clinical practice for patients without diabetes undergoing elective small and large bowel surgery,” they added.