ultrasound guided ESP Block after anaesthesia induction

After the induction of anaesthesia, pre-incisional port-site infiltration will be performed by the same surgeon every time with 20 ml of Local anesthetic (LA) mixture that will be divided equally between port sites

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.

Nalbuphine consumption in mg.(equivalent to morphine dose)

The NRS is a segmented numeric version of the Visual Analog Scale (VAS) in which a respondent selects a whole number (0-10 integers).