Spinal anesthesia for lengthy lower limb orthopedic surgeries: dexmedetomidine plus fentanyl versus dexmedetomidine

Abstract

BackgroundSpinal anesthesia is efficient but of limited duration. Intrathecal dexmedetomidine prolongs the sensory and motor blockade of bupivacaine. Dexmedetomidine-opioids combination displayed a clinically controversial interaction. Our proposal is that fentanyl may augment the block characteristics of dexmedetomidine using proper doses.Patient and methodsThis is a randomized double-blinded study. The included patients were scheduled for orthopedic procedures expected to extend more than 4 h. Patients were allocated into two groups each of 23. Group D received intrathecal bupivacaine 20 mg 0.5% + dexmedetomidine 10 μg. Group DF received bupivacaine 20 mg 0.5% + dexmedetomidine 10 μg + fentanyl 25 μg. The spinal block characteristics and adverse effects were determined. Data were compared by t test, Mann-Whitney, and chi-square tests as appropriate.ResultsThere was no significant difference between the two groups as regards spinal block and hemodynamic characteristics. The addition of fentanyl provided earlier time to T10 sensory block, lower midazolam and ephedrine utilization, but occasional mild itching. Postoperatively, the time to the first analgesic request, morphine consumption, and patient’s satisfaction were not different.ConclusionThe addition of fentanyl does not prolong the sensory and motor block characteristics of dexmedetomidine. In favor of dexmedetomidine-fentanyl combination was the less hypotension and less sedative requirement.Trial registrationPan African Clinical Trials RegistryTrial number: PACTR201703002122189 on 28 March 2017.