Opioid versus Nonopioid Analgesia for Craniotomy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Background: Despite the use of intraoperative opioid analgesia, postoperative pain is often reported by patients undergoing craniotomies. Opioids also cause undesirable side effects in neurosurgical patients. Hence, the role of nonopioid analgesia has been explored for craniotomies in recent years.

Methods: This systematic review evaluated evidence from randomized controlled trials (RCTs) comparing opioid and nonopioid analgesia during craniotomies regarding postoperative pain, recovery, and adverse events.

Results: Of the 10,459 records obtained by searching MEDLINE, Embase, and Web of Science databases, 6 RCTs were included. No difference was observed in pain scores between opioid and nonopioid analgesia at 1 and 24 hours after surgery: mean difference (MD), 1.11 units; 95% confidence interval [CI], -0.16 to 2.38, P = 0.09 and MD, -0.06 units; 95% CI, -1.14 to 1.01, P = 0.91, respectively. The time for first postoperative analgesic requirement was shorter with opioids but was not statistically significant (MD, -84.77 minutes; 95% CI, -254.65 to 85.11; P = 0.33). Postoperative nausea and vomiting (relative risk = 1.60; 95% CI, 0.96-2.66; P = 0.07) was similar but shivering (relative risk = 2.01; 95% CI, 1.09-3.71; P = 0.03) was greater in the opioid group than nonopioid group.

Conclusions: There were no important differences in clinical outcomes between the groups in our review. The GRADE certainty of evidence was rated low for most outcomes. Available evidence does not suggest superiority of intraoperative nonopioid over opioid analgesia for postoperative pain in patients undergoing craniotomy. More studies are needed to firmly establish the role of nonopioid intraoperative analgesics as an alternative to opioids in this population.