Ultrasound-guided Interscalene Block Versus Infraspinatus-Teres Minor Plane Block in Shoulder Arthroscopy

This study aims to compare the efficacy and safety of ultrasound-guided Interscalene block (ISB) versus Infraspinatus-Teres minor (ITM) interfacial plane block in shoulder arthroscopic surgery. A prospective, randomized clinical trial will be conducted with 46 patients. Approval was obtained from the Medical Ethics Committee (2022/0126), and written informed consent will be collected from all participants. Patients aged 20-70, ASA I-II, scheduled for arthroscopic shoulder surgery will be divided before the induction of general anesthesia (GA) into two groups: Group A: will receive the ultrasound guided ISB technique with a 15ml solution of 7.5ml lidocaine 2% and 7.5ml bupivacaine 0.5% be injected between the anterior and middle scalene muscles. Group B: will receive the ultrasound guided ITM block with the same anesthetic solution be injected between the infraspinatus and teres minor muscles. Researchers will examine the following outcomes; 1. Primary outcome measure: Efficacy of analgesia by Pain score; will be measured by Numerical Rating Scale (NRS) score (0=no pain,1-3=mild,4-6=moderate,7-9=sever,10=most sever) at postoperative 12 hour. 2. Secondary outcome measures: 1. Duration of analgesia, starting from recovery from general anesthesia (GA) to 1st time giving the patient rescue analgesia ( measured by NRS pain score at 0, 6 ,12, 18 and 24 postoperative hours) 2. Risk of complications from techniques 3. Patient satisfaction after surgery. 4. Rescue analgesic consumption 5. Hemodynamics monitoring; measurements of heart rate and mean arterial blood pressure before induction of anesthesia and every 15 minutes during surgery till end of surgery