Effects of intra-operative maintenance of general anaesthesia with propofol on postoperative pain outcomes - a systematic review and meta-analysis.

Propofol is used both for induction and maintenance of anaesthesia. Recent evidence shows that propofol has analgesic properties. This meta-analysis evaluated differences in postoperative analgesia between general anaesthetic maintenance with intravenous propofol and inhalational anaesthetics. Fourteen trials met inclusion criteria and were included. Our outcomes were pain scores 2 and 24 h after surgery. No significant difference in pain scores was found at 2 h after surgery (Hedge's g (95% CI) -0.120 (-0.415-0.175) (p = 0.425). Propofol was associated with a statistically significant, albeit marginal, reduction in pain scores 24 h after surgery (Hedge's g (95% CI) -0.134 (-0.248 to -0.021) (p = 0.021). Data were insufficient to allow a meaningful analysis regarding 24-h morphine-equivalent consumption. Propofol was associated with reduced postoperative nausea and vomiting (relative risk (95%CI) 0.446 (0.304-0.656) (p < 0.0001). In conclusion, this meta-analysis suggests that propofol improves postoperative analgesia compared with inhalational anaesthesia 24 h after surgery, with a lower incidence of nausea and vomiting.