Comparative study on efficacy of ultrasound guided transversus abdominis plane block using dexmedetomidine versus dexamethasone as adjuvant to levobupivacaine for post-operative analgesia following caesarean section under sub arachnoid block.

Ceasarean section is a common surgical procedure performed to deliver a baby when a vaginal delivery is not possible. Post operative pain management after a cesarean section is crucial for both mother and baby.The management of postoperative pain in caesarean section is often approached using multimodal analgesia, incorporating both pharmacological and non-pharmacological strategies. One such strategy is the use of regional anaesthesia techniques, such as the Transversus Abdominis Plane (TAP) block, which has been shown to provide effective analgesia by blocking sensory innervation to the anterior abdominal wall. When combined with adjuvants like dexamethasone and dexmedetomidine, the efficacy of the TAP block may be enhanced, providing prolonged and more effective pain relief. The TAP block targets the T6-L1 spinal nerves, which provide sensory innervation to the anterior abdominal wall, including the skin and muscles. By blocking pain signals from the surgical site, the TAP block helps reduce the need for systemic opioids, thus mitigating the side effects associated with their use, such as nausea, vomiting, and constipation. It is a relatively simple, minimally invasive procedure with a low risk of complications when performed correctly. 

The aim of the study  is to compare on efficacy of ultrasound guided transversus abdominis plane block using dexmedetomidine or dexamethasone as adjuvant to levobupivacaine for post-operative analgesia following caesarean section under sub arachnoid block.

Objectives

PrimaryTo assess and compare efficacy of post operative pain relief in both groups.

Secondary

1.      To record the duration of post operative analgesia of block which is determined by time to first additional rescue analgesic administration.

2.      Total amount of additional analgesic consumption.

3.      To study side effects like nausea and vomiting and sedation.

Study Groups .Subjects will be divided into two study groups.

 Group 1.Patients will receive a local anesthetic solution consisting of 40 mL of 0.125% (1.25mg/ml) levobupivacaine and 8 mg of dexamethasone. It will be equally distributed bilaterally in the TAP block

Group 2. Patients will receive a mixture of 40 mL of 0.125% (1.25mg/ml) levobupivacaine and dexmedetomidine with a total dose of 0.5 µg/kg body weight. It will be equally distributed bilaterally in the TAP block.

Subarachnoid block will be given at either L3-L4 or L4-L5 inter-vertebral spaces where 2-2.5ml (i.e. 5mg/ml) of hyperbaric bupivacaine will be injected using 25-gauge Quincke spinal needle. After surgery TAP block is will be given using ultrasonography after the closure of the skin. A high frequency linear probe (6-13 MHz) will be used to give block at triangle of petites in supine position bilaterally under all aseptic measures. The linear array ultrasound probe will be positioned at the level of the umbilicus on the anterolateral abdominal wall, between the subcostal edge and the iliac crest. The transversus abdominis muscle (TA) , internal oblique muscle (IO), and external oblique muscles (EO) will be recognized. The IO and TA muscles form a hypoechoic line that points to the fascial plane. Under ultrasound guidance and after confirming a negative aspiration result, a local anaesthetic solution combination will be administered using a 25-gauge 10 cm long Sono-plex needle. In this study, postoperative pain will be evaluated in both groups using the VAS (Visual Analog Scale).Time of first dose of rescue analgesia consumption will be recorded and total analgesic consumption will be recorded in the first 24 hours after surgery.