The effects of epidural/spinal opioids in labour analgesia on neonatal outcomes: a meta-analysis of randomized controlled trials.

PURPOSE: Epidural/spinal opioids are increasingly used to relieve parturients' pain in labour. Some studies indicate that opioids can induce side effects in neonates, such as respiratory depression and neurobehavioural changes. This meta-analysis aimed to clarify the effects of opioids in labour analgesia on neonates. SOURCE: PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and EMBASE™ were searched for relevant randomized controlled trials (RCTs). The neonatal data of Apgar scores, Neurological and Adaptive Capacity Scores (NACS), and umbilical cord pH values were extracted. Statistical analyses were carried out using Review Manager 5.2 and Stata(®) 10. PRINCIPAL FINDINGS: Twenty-one trials with 2,859 participants were included in our meta-analysis. No difference in the incidence of Apgar scores < 7 was shown between the opioid and control groups at one minute (risk difference [RD] 0.0%, 95% confidence interval [CI]: -3.0 to 2.0, P = 0.78; I (2) = 0%, 95% CI: 0 to 50) and at five minutes (RD -1.0%, 95% CI: -2.0 to 1.0, P = 0.31; I(2) = 0%, 95% CI: 0 to 50). No significant differences were found in the NACS at two hours (mean difference [MD] -0.35, 95% CI: -1.70 to 1.01, P = 0.62; I(2) = 0%, 95% CI: 0 to 79) and at 24 hr (MD -0.45, 95% CI: -1.36 to 0.46, P = 0.33; I(2) = 3%, 95% CI: 0 to 26). Also, no significant differences were found in umbilical cord artery pH (MD -0.02, 95% CI: -0.06 to 0.03, P = 0.48; I(2) = 80%, 95% CI: 46 to 92) and vein pH (MD -0.03, 95% CI: -0.07 to 0.00, P = 0.08; I(2) = 77%, 95% CI: 36 to 91). No significant publication bias was found. CONCLUSION: The common doses of fentanyl and sufentanil used with an epidural/spinal technique in labour analgesia are safe for neonates up to 24 hr after delivery. In future studies, more attention should be paid to the long-term side effects in neonates.