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To investigate postoperative pain variations in vitreoretinal surgeries conducted with combined regional-general anesthesia or general anesthesia.

Systematic review and meta-analysis.

A systematic search of the PubMed, Embase, and Cochrane Library databases was conducted to identify relevant randomised controlled trials (RCTs) published before December 26, 2023. Studies comparing vitreoretinal surgeries conducted under combined anesthesia to general anesthesia were included, while studies using only regional anesthesia were excluded. The quality of the studies was assessed using the Cochrane Collaboration risk of bias tool, and the results are presented as odds ratios (ORs) or standardised mean differences (SMDs) with 95% confidence intervals (CIs). I2 statistic was calculated to assess heterogeneity. The primary outcomes in our study included the proportions of patients needing as-needed postoperative analgesics, dosage of as-needed postoperative analgesia medications, and time to the first demand for as-needed postoperative analgesia. The secondary outcomes included postoperative pain scores at 0.5, 1, 2, 4, 6, 12, 24 hours (h), duration of surgery and anesthesia, and percentage of patients experiencing postoperative nausea and vomiting (PONV).

A total of 19 RCTs involving 1314 patients were analysed. Combined anesthesia was associated with lower proportions of patients needing as-needed postoperative analgesics (OR, 0.218 95% CI, 0.114 to 0.418, I2 = 55.2%), reduced dosage of as-needed postoperative analgesia medications (SMD, -1.429, 95% CI, -2.395 to -0.462, I2 = 90.4%), and longer time to the first demand for as-needed postoperative analgesia compared with general anesthesia alone (SMD, 2.650, 95% CI, 1.169 to 4.132, I2 = 96.5%). The effect of additional regional anesthesia lasted for 6 hours (0.5h SMD, -1.471, 95% CI, -2.498 to -0.444, I2 = 90.5%; 1h, -1.507, -2.309 to -0.705, 92.7%; 2h -1.487, -2.300 to -0.674, 93.2%; 4h -1.052, -1.708 to -0.396, 89.5%; 6h -1.053, -1.932 to -0.174, 93.4%; 12h -0.286, -0.648 to 0.076, 57.1%; 24h -0.297, -0.624 to 0.029, 64.0%). Combined anesthesia decreased PONV risk without affecting the surgical or anesthesia duration.

Combined anesthesia demonstrated additional postoperative analgesic effects versus general anesthesia only. Further research is needed to validate the results of our study and to identify vision-threatening complications.