Exploratory Analysis of Impact of Gabapentin on Incidence of Postoperative Nausea and Vomiting in Patients Undergoing Knee and Hip Arthroplasty With Neuraxial Anesthesia.

The incidence of postoperative nausea and vomiting (PONV) is unknown in neuraxial anesthesia for orthopedic surgery. The effect on PONV of adding gabapentin to an evidence-based antiemetic regimen as part of an opioid-sparing analgesic protocol is also unknown in this population. A retrospective analysis of all adults undergoing hip and knee arthroplasty and receiving neuraxial anesthesia in 2017 was conducted. The overall incidence of PONV was assessed. Additionally, PONV incidence was assessed for all combinations of gabapentin, dexamethasone, and/or ondansetron (in addition to propofol infusion) and compared with propofol alone. The PONV risk ratios were estimated, adjusting for age and PONV risk score. The overall incidence of PONV was 14.0%. The addition of gabapentin to propofol was associated with reduced PONV (multivariable risk ratio [mRR], 0.6; 95% CI, 0.4-1.0) vs propofol alone. Dexamethasone with propofol was associated with reduced PONV (mRR 0.6; 95% CI, 0.4-1.1) vs propofol alone, although not statistically significant. The addition of both gabapentin and dexamethasone to propofol was associated with stronger reduction in PONV (mRR 0.3; 95% CI, 0.1-0.7) vs propofol alone. Adding ondansetron to propofol showed little benefit. Gabapentin and dexamethasone are effective in reducing PONV in patients undergoing knee and hip arthroplasty with neuraxial anesthesia.