Serratus anterior plane block for hybrid transthoracic esophagectomy : a pilot study

Background: Pain is a major limiting factor in patient’s recovery from major thoracic surgical procedures. Thoracic epidural analgesia (TEA), the current gold standard of perioperative management, has contraindications, can technically fail, and carries a risk of complications such as epidural abscess and spinal hematoma. The ultrasound-guided serratus anterior plane (SAP) block is a promising regional analgesia technique. Objectives: Since the anatomic space involved in the SAP block corresponds to the area exposed by the surgeon during right posterolateral thoracotomy, we investigated the feasibility of a “surgically guided” continuous SAP block as an alternative to TEA in selected esophagectomy patients. Study design: This was a pilot case-series study. Setting: This study was carried out in a tertiary-care university hospital. Methods: The demographic and clinical data of patients in whom the continuous SAP block was performed were retrieved from a prospectively maintained database of hybrid (laparoscopy plus right thoracotomy) Ivor Lewis esophagectomy. The SAP block was performed upon closure of the thoracotomy incision using a 19-gauge catheter tunnelized subcutaneously and positioned in the deep plane between the serratus anterior muscle and the ribs. A bolus dose of 30 mL of levobupivacaine 0.25% was injected, followed by a continuous infusion of the 0.125% solution at 7 mL/h until postoperative day 4. Results: Between January 2016 and July 2016, seven (20%) out of 37 esophagectomy patients underwent a SAP block rather than TEA for the following reasons: inability to insert the epidural catheter, antiaggregation or anticoagulant therapy, or unplanned thoracotomy. The procedure was uneventful in all patients. Only two patients required rescue analgesia on day 1. Conclusion: Continuous SAP block under direct vision is feasible and safe. This novel “surgically guided” application of the SAP block may be useful in case of failure or contraindications to TEA.