Programmed intermittent bolus for erector spinae plane block versus intercostal nerve block in minimally invasive direct coronary artery bypass surgery: a randomized controlled trial.

Objective: Continuous intercostal nerve block (ICNB) has been shown to offer effective pain relief after minimally invasive direct coronary artery bypass (MIDCAB). The erector spinae plane block (ESPB) could represent a viable alternative approach. This study aimed to compare the analgesic effect of programmed intermittent bolus(PIB) for ESPB to ICNB in patients undergoing MIDCAB.

Methods: A prospective, open-label, randomized controlled trial was conducted. Eighty patients scheduled for MIDCAB were randomized into two groups (n = 40 per group). ESPB using a PIB injection was performed in the ESPB group, while ICNB was performed in the ICNB group. The primary outcome was numerical rating scale (NRS) pain scores at movement immediately after extubation. Secondary outcomes included the cumulative area under the curve (AUC) of the pain scores, perioperative analgesic consumption, adverse events and recovery data.

Results: A total of 73 patients were included in the modified intention-to-treat analysis and 71 patients in the per-protocol analysis. There was no significant difference in numeric rating scale (NRS) scores at rest or movement between the two groups immediately after extubation, at 8, 24 and 48 h. The cumulative area under the curve (AUC) of the time NRS curve until 48 h after extubation and the necessity of rescue analgesics did not differ to a statistically significant degree between the two groups. Compared with the ICNB group, the ESPB group had significantly lower usage of intraoperative sufentanil (93.8 ± 33.6 vs. 128.9 ± 48.4 µg; p = 0.001).

Conclusions: Postoperative analgesic effect between ESPB and ICNB did not differ in patients after MIDCAB.

Trial Registration: Chinese Clinical Trial Registry (ChiCTR1900022388, retrospectively registered on Apr 09, 2019).