Comparison of Superior Brachial Trunk Block and Peri-capsular Nerve Group Block of Shoulder Joint in Arthroscopic Shouldersurgery: A Randomized Non-Inferiority Trial

Early postoperative pain immediately following shoulder surgery is a major concern and cause of distress for patients and orthopedic surgeons. Adequate pain control is vital for all aspects of the patient’s recovery, hence regional anaesthesia plays an important role in decreasing the pain following shoulder surgeries. Superior Brachial trunk block a variant of conventional interscalene block is found to be non inferior to latter in providing adequate post operative analgesia. However superior brachial trunk block like interscalene block is associated with incidence of hemi diaphragmatic paresis due to local anaesthetic spread around the phrenic nerve. PENG block around shoulder joint is a new motor sparing block that causes only sensory blockade that needs to be evaluated.

Standard Pre-Anesthetic Check Up will be done preoperatively and no premedication will be given. Informed and written consent will be taken from the patients while educating them about PCA machine and 11-points numerical rating scale for pain. When the patient arrives pre-op holding area: Baseline ipsilateral dome Diaphragmatic Ultrasound (T1) will be done for diaphragmatic excursion. Patient is randomly allocated via a sealed envelope to get either a superior brachial trunk block or PENG block around shoulder. In the operating room: standard monitoring will be done (HR, RR, NIBP, SpO2, EtCo2). Depending on the group to which the patient will be allocate either superior brachial trunk block or PENG block around shoulder will be given. Under aseptic conditions high frequency linear transducer will be placed over the interscalene region and superior brachial trunk block will be carried out For patients allocated to PENG block round shoulder group, high frequency linear transducer will be placed longitudinally between coracoid process and head of humerus and drug will be injected between subscapularis tendon below and deltoid muscle above. Drug to be used: 0.5% ropivacaine 15ml in both the blocks. Drug injected time will be taken as T0. At T20 motor blockade will be assessed. Patient will be induced with fentanyl 2mcg/kg, propofol 1.5 – 2 mg/kg, atracurium 0.5mg/kg followed by tracheal intubation. Maintenance: sevoflurane with air and oxygen. Intra operatively bolus of fentanyl 0.5mcg/kg will be given if heart rate and blood pressure increase by > 20% of baseline. Complications if any will be managed as per standard protocol. At the end of surgery reversal will be done with neostigmine and glycopyrrolate followed by extubation, and the patient will be shifted to PACU. Post operatively: USG will be done to find out diaphragmatic excursion. PCA pump will be attached to the patient that delivers 25mcg of fentanyl on demand with a lockout interval of 15 mins, with no basal dose. Inj PCM 10-15 mg/kg 6 hourly will be supplemented and injection ketorolac 0.5mg/kg iv 12 hourly as a part of multimodal analgesia, and if patient complains of pain more than 4/10 on VAS then 75-100 mcg/kg of morphine will be given. After 24 hrs. PCA pump will be disconnected and total fentanyl consumed will be noted. In addition, rescue opioids given if any are also noted, pain according to VAS from 0 – 10 is noted, patient satisfaction, surgeon satisfaction and complications if any will be noted down. The collected data will be analyzed using SPSS 20.1 (IBM Corp). Parametric variables will be described as mean ± standard deviation and qualitative variables were described as number (percentage) and as median and range.