Does Erector Spinae Plane Block Have a Visceral Analgesic Effect?: A Randomized Controlled Trial

The visceral analgesic efficacy of erector spinae plane block (ESPB) is still a matter of debate. This study attempted to investigate the visceral analgesic efficacy of ESPB in clinical setting. After randomized, we performed ultrasound-guided bilateral rectus sheath block (RSB), which was aimed to prevent postoperative somatic pain on all patients who underwent laparoscopic cholecystectomy (LC). Ultrasound-guided bilateral ESPB at T7 level was performed only to the intervention group to provide the visceral analgesic block. The intraoperative requirement for remifentanil (P=0.021) and the cumulative fentanyl consumption at postoperative 24-hours was significantly lower in the ESPB group (206.5 +/- 82.8 mu g vs.283.7 +/- 102.4 mu g, respectively; P=0.004) compared to non-ESPB group. The ESPB group consistently showed lower accumulated analgesic consumption compared with those in the non-ESPB group at all observed time-points (all P<0.05) after 2hours and the degree of the accumulated analgesic consumption reduction was greater (P=0.04) during the 24-hour postoperative period. Pain severity was lower in the ESPB group at 6-hours postoperatively. The significantly reduced opioid consumption in ESPB group may imply that while preliminary and in need of confirmation, ESPB has potential visceral analgesic effect. Therefore, performing ESPB solely may be feasible in inducing both somatic and visceral analgesia.