Comparative study of the efficacy of ultrasound guided erector spinae plane block and oblique subcostal transversus abdominis plane block for post operative analgesia after laparoscopic cholecystectomy.A randomized clinical trial

Laparoscopic Cholecystectomy is a minimally invasive surgery, which is the procedure of choice for the majority of patients with gallbladder pathologies. Intraoperative access is provided with small keyhole entries on abdominal wall. Laparoscopic Cholecystectomy causes moderate to severe postoperative pain which has different components; incisional pain from the trocar site(somatic pain),and local visceral pain(deep abdominal pain).Many patients also suffer from shoulder pain which is due to subdiaphragmatic irritation, transmitted by phrenic nerve referred to C4 dermatome. Multimodal approaches with NSAIDS, dexamethasone, gabapentinoids, opioids, local anesthetic infiltration to port sites, epidural analgesia have been tried to attenuate postoperative pain after Laparoscopic Cholecystectomy. Inadequate postoperative pain control has many consequences ,including patient dissatisfaction, transition into chronic pain, delayed discharge from the hospital, increased healthcare costs etc. Hence, adequate Postoperative Pain Management(POPM) should be major issue and challenge for the anesthesiologists. Ultrasound-guided oblique subcostal transversus abdominis plane block(OSTAP)  blocks somatic pain fibers and the deeper fibers of the anterior and lateral cutaneous branches of the 9th to 11th thoracic intercostal nerves. Ultrasound-guided erector spinae plane block (ESPB) is a relatively new technique used for analgesia. It targets the ventral rami, dorsal rami, and rami communicantes of the spinal nerves and thus results in the blockage of both somatic and visceral pain. Our study aimed to compare these two blocks using low concentration of Local anesthetic (0.25% Levobupivacaine).