Low-volume C5-6 interscalene and supraclavicular nerve blocks for arthroscopic shoulder surgery: A case series.

Abstract

Interscalene block (ISB) is considered a gold standard regional anesthesia technique for shoulder surgery. Conventionally, 20 ml of local anesthetic is used for ISB. Nevertheless, this high-volume traditional ISB is associated with a high incidence of hemidiaphragmatic paresis due to phrenic nerve block. Recent evidence suggests that low-volume ultrasound-guided (USG)-ISB can provide effective analgesia whilst avoiding complications. Thirty patients of American Society of Anaesthesiologist ASA status I/II undergoing arthroscopic rotator cuff repair surgery under general anesthesia were administered low-volume USG-ISB and supraclavicular nerve block (SCNB). The block provided effective analgesia in 90% (27/30) of the patients as their visual analog score was below 4 at all times in the 24-h postoperative period. Only three patients required a single dose of rescue analgesic (diclofenac 50 mg iv) in the 24-h postoperative period. In postoperative recovery, two patients (6.67%) had desaturation due to hemidiaphragmatic paresis and three patients (10%) had a transient neurological deficit. In conclusion, low-volume USG-ISB with SCNB provides effective analgesia for arthroscopic rotator cuff repair surgery. The advantages of this technique include a low incidence of respiratory and neurological complications.