Ultrasound-guided serratus anterior plane block combined with parasternal block in subcutaneous implantable cardioverter defibrillator implantation: Results of a pilot study.

Background The standard approach to subcutaneous defibrillator (S-ICD) implantation often requires general anesthesia or anesthesiologist-delivered deep sedation. Ultrasound-guided serratus anterior plane block (SAPB) combined with parasternal block (PSB) has been proposed in order to provide anesthesia/analgesia and to reduce the need for sedation during S-ICD implantation. In this pilot study, we compared the double-block approach (SAPB + PSB) with the single-block approach (SAPB only) and with the standard approach involving local anesthesia and sedation. Methods We prospectively enrolled 22 patients undergoing S-ICD implantation: in 10, the single-block approach was adopted; in 12, the double-block approach. As a control group, we retrospectively enrolled 14 consecutive patients who had undergone S-ICD implantation under standard local anesthesia and sedation in the previous 6 months. Intra- and postprocedural data, including patient-reported pain intensity, were collected and compared in the three study groups. Results The double-block approach was associated with a shorter procedure duration than the single-block and standard approaches (63.3 +/- 7.9 vs 70.1 +/- 6.8 vs 76.9 +/- 7.8 min; P < .05) and with a lower dose of local an aesthetic for infiltration (18.9 +/- 1.7 vs 27.5 +/- 4.6 vs 44.6 +/- 4.0 cc; P < .001). Both the double- and single-block approaches were associated with lower pain intensity at the device pocket and the lateral tunneling site (P < .05). The double-block approach proved superior to the other two approaches in controlling intraoperative pain at the parasternal tunneling site (P < .05). Conclusions In our study, SAPB combined with PSB was superior to SAPB alone and to the standard approach in controlling intraoperative pain during S-ICD implantation. In addition, this approach resulted in shorter procedure durations.