Comparison of Ultrasound-Guided Axillary Brachial Plexus Block Properties in Diabetic and Non-diabetic Patients: A Prospective Observational Study

Background and objectives: The impact of diabetes mellitus (DM) on the practice of peripheral nerve block anesthesia was mostly investigated in animal researches, and effects on human models are required to be clarified. The investigators performed this study to explore whether the presence of DM would affect the outcomes of axillary brachial plexus blocks (ABPBs) in patients undergoing elective forearm and/or hand surgery. The primary hypothesis was that the sensory block duration would be delayed in diabetic patients.

Methods: After obtaining ethics committee approval and written informed consent, 71 patients with American Society of Anesthesiologists (ASA) physical status I-III and aged between 40 and 75 years were enrolled to the study. Diabetic patients were included in Group DM and non-diabetics were included in Group NODM. All received ultrasound-guided ABPBs with the mixture of 10 mL lidocaine 2% and 20 mL bupivacaine 0.5%. Postoperatively, patients were administered paracetamol as rescue analgesics, if numeric rating scale (NRS) was ≥4. Our primary outcome was sensory block duration, and secondary outcomes were sensory and motor block onset times, motor block duration, time-to-first-pain (numeric rating scale (NRS) ≥4), postoperative NRS scores, and rescue analgesic consumption (NRS) ≥4) through the postoperative first 2 days. All outcomes were assessed by a blinded investigators.