title: Low-Dose Naloxone for Prophylaxis of Postoperative Nausea and Vomiting: A Systematic Review and Meta-analysis.
abstract: OBJECTIVE
  To determine whether postoperative administration of low-dose intravenous naloxone decreases the incidence of postoperative nausea and vomiting (PONV) and its impact on postoperative opioid requirements and pain scores.
  
  
  METHODS
  Meta-analysis of nine randomized controlled trials.
  
  
  METHODS
  A total of 946 adult and pediatric patients who received low-dose intravenous naloxone for 24 hours after various surgeries.
  
  
  RESULTS
  Systemic literature searches of the Cochrane Central Register of Controlled Trials, Evidence-Based Medicine Reviews, PubMed, and Ovid MEDLINE databases were conducted. Among the relevant studies, data extraction and bias assessment determined the trials for inclusion in this meta-analysis. Nine randomized controlled trials met inclusion criteria. Naloxone demonstrated a reduced risk of postoperative nausea (risk ratio [RR] 0.80, 95% confidence interval [CI] 0.67-0.95, p=0.01) in a pooled analysis of eight of the nine studies. However, naloxone did not decrease the risk of postoperative vomiting in a collective assessment of all nine trials (RR 0.83, 95% CI 0.63-1.09, p=0.18). Subgroup analysis of continuous-infusion naloxone found further reductions in nausea and vomiting, but these findings were limited to 186 of the 946 patients. Three studies recorded antiemetic doses and found an overall dose reduction (RR 0.64, 95% CI 0.42-0.96, p=0.03). Compared with controls, naloxone prophylaxis of PONV did not significantly change cumulative postoperative opioid needs (mean difference 0.29 mg, 95% CI -3.55 to 4.13 mg, p=0.88) among five trials, nor visual analog scale pain scores (mean difference -0.11, 95% CI -0.26 to 0.05, p=0.18) in six studies.
  
  
  CONCLUSIONS
  This pooled analysis of data suggests that low-dose naloxone plays no role in preventing PONV, while exhibiting no significant effects on postoperative opioid needs and pain scores. The reduction demonstrated in postoperative nausea did not translate into decreases in postoperative vomiting.
authors.affiliation: Department of Pharmacy, Wingate University School of Pharmacy, Wingate, North Carolina.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Barrons
authors.affiliation: Department of Pharmacy, Wingate University School of Pharmacy, Wingate, North Carolina.
authors.forename: Joseph Andrew
authors.initials: JA
authors.lastname: Woods
mesh_terms: D000701:Analgesics, Opioid / Q000008:administration & dosage; D006801:Humans; D007262:Infusions, Intravenous; D009020:Morphine / Q000008:administration & dosage; D009270:Naloxone / Q000008:administration & dosage*; D009292:Narcotic Antagonists / Q000008:administration & dosage*; D010149:Postoperative Pain / Q000453:epidemiology / Q000517:prevention & control*; D020250:Postoperative Nausea and Vomiting / Q000453:epidemiology / Q000517:prevention & control*; D065129:Pre-Exposure Prophylaxis / Q000379:methods*; D016032:Randomized Controlled Trials as Topic / Q000379:methods
chemical_list: D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D009270:Naloxone; D009020:Morphine
keywords: anesthesia; infusion; morphine; naloxone; nausea; opioids; postoperative; vomiting