Abstract

Background and Objectives: The gold standard for acute postoperative pain management in major abdominal surgeries is thoracic epidural analgesia (TEA) and this was proved by a lot of studies, systematic reviews and metaanalyses. However, TEA is sometimes contraindicated and may cause serious risks. Rectus Sheath Block (RSB) is effective for the abdominal surgeries with midline abdominal incisions as local anesthetics will be injected within the posterior rectus sheath bilaterally leading to intense pain relief for the middle anterior wall extending from the xiphoid process to the symphysis pubis. The aim of the study was to assess intra and post-operative RSB versus intra and post-operative TEA, in patients undergoing elective major abdominal cancer surgery with midline incisions.

Methods: This randomized, blinded, was registered at www.clinicaltrials.gov at no.: “NCT03460561” and was approved by local ethics committee of South Egypt Cancer Institute, Assiut University, Egypt. One hundred adult patients, (ASA grade II and III), scheduled for major elective abdominal cancer surgery with Medline incision, were randomly divided into two groups, (50 patients each); TEA group: patients in this group received TEA with standard GA and intra-operative analgesia was started before skin incision by injecting epidural bolus dose of 0.1 ml/kg of (0.125% levo-bupivacaine+fentanyl 2 μg/ml). Postoperative analgesia was provided through PCEA by injecting a bolus dose of 3 ml then continuous infusion of 0.1 ml/kg of mixture of (0.0625% levo-bupivacaine+fentanyl 2 μg/ml) for 48 hours postoperative. RSB group: patients in this group received standard GA plus ultrasound (U/S) guided rectus sheath block by a volume of 20 mL of (0.25% levo-bupivacaine+fentanyl 30 μg) in saline on either side. Before end of surgery and before closure of abdominal wall, bilateral surgically placed catheters in rectus sheath plane aiming to provide post-operative analgesia using the following; 20 mL of (0.125% levo-bupivicaine+Fentanyl 30 μg) every 12 hours in to each catheter for 48 hours. Perioperative hemodynamics (MAP and HR) were recorded. Postoperative pain was assessed over 48 hour post operatively using (VAS). Total fentanyl consumption, Peak expiratory flow rate (PEFR), postoperative and side effects of the drugs and duration of ICU and hospital stay were recorded.

Results: We found a significant reduction in VAS pain scores (at rest and during cough) in both group at all postoperative period but fentanyl consumption was significantly lower in TEA group. Also we found a significant reduction in intra-operative hemodynamics (mean arterial pressure and heart rate) in TEA group in comparison to RSB group while there was minimal statistically significant reduction in postoperative MAP and heart rate. The incidence of other postoperative complications such as sedation, nausea and vomiting were comparable in both groups.

Conclusion: Rectus sheath block was not inferior to thoracic epidural analgesia in reduction of pain intensity after major abdominal cancer surgeries, and associated with hemodynamic stability along the 48 hours postoperative without procedure related adverse events or decreasing PEFR.

Keywords: Rectus sheath block; Thoracic epidural analgesia; VAS scale; Abdominal cancer surgeries