Ultrasound-Guided Mid-Point Transverse Process to Pleura Block for Thoracotomy Incisions

Analgesic Efficacy of Pre-emptive Ultrasound-Guided Mid-Point Transverse Process to Pleura Block for Patients Undergoing Posterolateral Thoracotomy Incisions: Randomized Controlled Trial

This study is designed to investigate the analgesic efficacy of pre-emptive ultrasound-guided midpoint transverse process to pleura (MTP) block for posterolateral thoracotomy in cardiothoracic surgeries.

Preemptive preoperative analgesia was first proposed, over the years it has been gradually regarded as an intervention given before incision, facilitating mobilization and functional rehabilitation after surgery, reducing postoperative opioid consumption, decreasing the incidence of adverse events and improving patient satisfaction. The Mid Transverse Process to Pleura block, described by Costach et al. involves deposition of drug midway between the transverse process and pleura. Costach et al. postulated that the local anesthetic deposited at this point may reach the paravertebral space through several possible mechanisms, such as spread medially through the gap between the superior costotransverse ligament (SCTL) and vertebral bodies, through fenestrations in SCTL, and laterally through the internal intercostal membrane

Patients will receive midpoint transverse process block after induction of general anesthesia and before surgical incision

Patients will receive general anesthesia and the same intervention steps will be performed i.e., the block under investigation but instead of local anesthetic a placebo (2ml normal saline) will be injected (sham block)

After marking the level of the incision by surgeon (commonly T5- T6) The patient will be situated in the lateral position, the block area will be sterilized with povidine-iodine, and high -frequency linear ultrasound probe will be placed oblique parasagittally 3 cm lateral to the spinous process at the level of skin incision. 100-mm short bevel echogenic needle (Contiplex, B.Braun, Germany) will be inserted in plane from cranial to caudal direction. The desired end point of the needle tip will be the midpoint of the line between the posterior border of transverse process and the pleura titrated bolus of 20 ml of 0.25% bupivacaine and dexamethazone 8 mg will be injected at the target site. At end of the surgery general anaesthesia will be stopped with reversal of muscle relaxation and awakening of patient

General anesthesia will be induced with the same protocol and MTP block will be done but with injection of placebo (2 ml normal saline) instead of local anesthetic . On arrival to the PACU postoperative Numerical Rating scale at rest and coughing will be recorded, analgesia will be maintained with intravenous paracetamol 1 g every 8 h and required additional rescue analgesia (morphine) at any time will be calculated.

Postoperative pain will be assessed by the Numerical Rating Scale (NRS;0 no pain while 10 is the maximum pain) at 0,4,8,12,18, 24 hours during rest and cough. If the (NRS) is 4 or more, morphine 3mg will be titrated until pain relief is achieved using a short interval between boluses

Inclusion Criteria: Patients aged 21- and65 years old American Society of Anesthesiologists (ASA) II-III Scheduled for posterolateral thoracotomy operation under general anesthesia Exclusion Criteria: Patients with bleeding disorders, Mental or cognitive dysfunction History of chronic analgesic or drug abuse Allergy to local anesthetics Local infection at site of block