New technique targeting the C5 nerve root proximal to the traditional interscalene sonoanatomical approach is analgesic for outpatient arthroscopic shoulder surgery

Abstract

Study objectiveRegional anesthesia and analgesia for shoulder surgery is most commonly performed via interscalene nerve block. We developed an ultrasound-guided technique that specifically targets the C5 nerve root proximal to the traditional interscalene block and assessed its efficacy for shoulder analgesia. DesignProspective case series. SettingVanderbilt Bone and Joint Surgery Center. PatientsPatients undergoing shoulder arthroscopy at an ambulatory surgery center. InterventionsThirty-five outpatient shoulder arthroscopy patients underwent an analgesic nerve block using a new technique where ultrasound visualization of the C5 nerve root served as the primary target at a level proximal to the traditional interscalene approach. The block was performed with 15mL of 0.5% plain ropivicaine. MeasurementsPost anesthesia care unit pain scores, opioid consumption, hand strength, and duration of block were recorded. Cadaver dissection after injection with methylene blue confirmed that the primary target under ultrasound visualization was the C5 nerve root. Main resultsPain scores revealed 97% patients had 0/10 pain at arrival to PACU, with 91% having a pain score of 3/10 or less at discharge from PACU. Medical Research Council (MRC) hand strength mean (SD) score was 4.17 (0.92) on a scale of 1–5. The mean (SD) duration of the block was 13.9 (3.5) hours. ConclusionsA new technique for ultrasound-guided blockade at the level of the C5 nerve root proximal to the level of the traditional interscalene block is efficacious for shoulder post-operative pain control.