Comparison of duration of postoperative analgesia after lateral quadratus lumborum block versus subcostal transversus abdominis plane block in laparoscopic cholecystectomy- A randomised controlled study

Laparoscopic surgery is nowadays a
common technique used in variety of abdominal surgeries including
cholecystectomy, appendicectomy, inguinal hernia repair, hemicolectomy etc. Eventhough
post-operative pain after laparoscopy is lesser than in open operative
techniques, the abdomen stiffness due to the pneumoperitoneum (created as a
step of the laparoscopic approach) and operative manipulations  may cause severe postoperative pain that
will affect the patient satisfaction and the outcome of the surgery.1

The various modes of pain management include parenteral administration of opioids, NSAIDs, wound infiltration with local anaesthetics, neuraxial anaesthesia, peripheral nerve blocks.etc. Multimodal approach provide better pain control. But these techniques are associated with drawbacks- opioids are associated with vomiting, pruritus, oversedation and respiratory depression;NSAIDs  can cause nausea, vomiting and gastric irritation,etc. Regional anesthesia techniques can be used as sole anesthetic technique or adjuvant to general anesthesia for intra  operative and postoperative analgesia.2

The transversus abdominis plane (TAP)block, first introduced by Rafi in 2001 as a landmark-guided technique via the triangle of Petit to achieve a field block. It involves the injection of a local anesthetic solution into the plane between the internal oblique muscle and transversus abdominis muscle.The local anesthetic spread in this plane can block the neural afferents and provide analgesia to the anterolateral abdominal wall, as the thoracolumbar nerves originating from the T6 to L1 spinal roots run into this plane and supply sensory nerves to the anterolateral abdominal wall.3USG facilitates accurate placement of block needle and real time deposition of local anaesthetic, increasing both margin of safety and block quality.4

Quadratus lumborum block is a block of the posterior abdominal wall, “interfascial plane block” which is performed under ultrasound guidance. It was described by anaesthesiologist Dr. Rafael Blanco as a variant of TAP block in 2007.Today four types of QL block are performed which differ by the site of drug application. These are QLB1or lateral QLB, QLB2 or posterior QLB, QLB3 or anterior /transmuscular QLB and QLB4 or intramuscular QLB. QLB1 or lateral QLB implies the application of local anaesthetics on the lateral side of the QLM on the area of its contact with transverasalis fascia, at the level where tranversus abdominis muscle taper off to its aponeurosis.5

This study is aimed to compare and evaluate the analgesic effectiveness between Lateral QLB and  subcostal TAPB after laparoscopic cholecystectomy.