Does Patient-Controlled Infraclavicular Perineural Dexmedetomidine Increase the Duration of Postoperative Analgesia?

Objective: Peripheral nerve blocks are now used widely for postoperative analgesia and peripheral nerve catheters are widely utilized. Objective of this study was to investigate effect of perineural infusion of dexmedetomidine on the duration of postoperative analgesia retrospectively. Material & Methods: A total of 60 patients aged between 18 and 65 years were included in the study. Group 1 received infraclavicular patient-controlled perineural bupivacaine (0.1 %). Group 2 received infraclavicular patient-controlled perineural bupivacaine (0.1 %) + dexmedetomidine (200 mic/100 cc). Blood pressure, pulse, peripheral oxygen saturation modified ramsay sedation scale, visual pain scores, total amount of analgesics were recorded at the 0, 30, 60, 90 minutes and 2, 4, 6, 8, 12, 24 hours. Results: Systolic blood pressure was higher in Group 1 at the hour 6 (p: 0.007). Whereas, diastolic blood pressure was higher in Group 1 at the hours 4 and 6 (p: 0.000, p: 0.003). Heart rate was found to be higher in Group 2 at the hours 8, 12 and 24 (p: 0.004, p: 0.002, p: 0.002). Patients in Group 1 were found to significantly feel pain and need analgesics at the hours 4 and 6 (p: 0.002, p<0.05). The mean number of patient requests for analgesia was 5.8 +/- 1.4 times in Group 1 and 2.2 +/- 0.4 in Group 2 (p<0,05). None of the patients developed sedation/neurological deficits. Conclusion: Perineural infusion of dexmedetomidine combined with bupivacaine was found to increase the duration of postoperative analgesia, reduce 24-hour need for analgesia and have not any adverse effect at low doses.