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

PURPOSE: Patients with diabetes mellitus (DM) type 2 may have subclinical peripheral nerve neuropathy. We performed this study to compare the differences in duration of axillary brachial plexus blocks in patients with type 2 DM and without DM (NODM). Our hypothesis was that the sensory block duration would be prolonged in patients with DM.

METHODS: A total of 71 patients who were scheduled for elective forearm and/or hand surgery were enrolled in this study. Before surgery, they received ultrasound-guided axillary brachial plexus blocks with a mixture of 10 mL lidocaine 2% and 20 mL bupivacaine 0.5%. After surgery, all patients received 1 g paracetamol every 6 hours as needed. The primary end point was sensory block duration. Secondary end points were motor block duration, time until first pain (numeric rating scale [NRS] 4 or greater), highest NRS pain scores, and rescue analgesic consumption (NRS 4 or greater) through the first 2 postoperative days.

RESULTS: In all, 67 patients completed the study: 22 in the DM group and 45 in the NODM group. Sensory and motor block durations were longer in the DM group than in the NODM group (mean [range], 773.5 [479-1155] vs 375 [113-900] minutes, and 523 [205-955] vs 300 [110-680] minutes). Time until first pain was 855 (590-1,285) minutes in the DM group and 500 (200-990) minutes in the NODM group. The highest NRS scores were also significantly lower in the DM group at 6 and 12 hours. Paracetamol consumption was lower in the DM group through the first 2 postoperative days.

CONCLUSIONS: The presence of DM was associated with longer duration of the sensory block after axillary brachial plexus block.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.