Comparison of Analgesic Efficacy of US Guided ESP Block With Port Site Infiltration Following Laparoscopic Cholecystectomy

Patients will be placed on their right side. A high-frequency linear ultrasound probe will be placed in a longitudinal parasagittal orientation 2.5-3 cm lateral to the T9 spinous process. The erector spinae muscles will be identified superficial to the tip of the T9 transverse process. A 21G 10-cm needle will be inserted using an in-plane approach in a cranial to caudal direction. The tip of the needle will be placed into the fascial plane on the deep aspect of the erector spinae muscle. The location of the needle tip will be confirmed by visible fluid spread lifting the erector spinae muscle off the bony shadow of the transverse process on ultrasonographic imaging. A volume of 20 mL of LA mixture (10 mL of bupivacaine 0.5%, 5 mL of lidocaine 2% and 5 mL of normal saline to make a mixture totaling 20 ml.) will be injected. The same procedure will be repeated for the opposite side.

After the induction of anaesthesia, pre-incisional port-site infiltration will be performed by the same surgeon every time with 20 ml of the LA mixture. The volume will be divided equally between port sites. A total of four ports-supraumbilical, subxiphoid and two ports in the right subcostal area at mid-clavicular and anterior axillary line will be made.

Ultrasound will be used to identify the erector spinae muscles and to guide the LA mixture injection.

Bupivacaine 0.5% will be included in the injected LA mixture.

Lidocaine 2% will be included in the injected LA mixture.