Comparison of dexmedetomidine and remifentanil sedation in spinal anesthesia

Abstract

Comparison of dexmedetomidine and remifentanil sedation in spinal anesthesia Objective: In orthopedic procedures spinal anesthesia is often the preferred method. When performing a spinal anesthesia, sedation is also applied in order to tolerate the operation. Sedative agent that used needs provide rapid onset and recovery, should have minimal side effects. Our study aimed to compare the sedation quality, the hemodynamic and respiratory effects of remifentanil and dexmedetomidine infusion for sedation in patients undergoing spinal anesthesia during orthopedic procedures. Material and Method: For study 90 subjects (ASAI-III) who underwent lower extremity surgery under spinal anesthesia were included. The age ranged between 20 and 60 years. This study is a prospective, randomized, controlled study. For spinal anesthesia, between L4-L5 distance, 2 ml of 0.5% hyperbaric bupivacaine was administerd and unilateral spinal anesthesia was achieved. In group 1, 20 ml / 10-minute loading dose followed by 15 ml/h infusion of 0.9% NaCl solution. In group 2, 0.5 mcg/kg (20 ml) 10-minute loading dose followed by 0.2 mcg/ kg/h dexmedetomidine infusion. In group 3, 0.5 mcg/kg (20 ml) 10-minute loading dose followed by 0.1 mcg/ kg/h remifentanil infusion. Of the cases, before the spinal block (BB), after the block (AB), at the 1 st , 5 th , 10 th , 15 th , 20 th minute of sedation and 10-minute intervals until the end of operation; mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), peripheral oxygen saturation (SPO2), sedation and nausea, vomiting, bradycardia, hypotension, desaturation, respiratory depression such side effects have been recorded. Results: The age, sex, weight, height averages and duration of operation did not significantly differed between groups. In group 3 HR was observed significantly lower than group 1 and 2 (p<0.05). At all times MAP measurements significantly decreased in all groups when compared with before sedation measurements (p<0.05). There was no significant difference between the groups in terms of respiratory rate and SPO2. When the Ramsay Sedation Scores (RSS) were compared; in group 3, a significant increase was observed at 1 th minute of sedation when compared with before sedation scores (p<0.05). In group 2 and 3 no significant difference was observed between before sedation and after sedation scores. There was also no significant difference between RSS scores and complication distrubition between groups. Conclusion: Remifentanil used for sedation, during spinal anesthesia, provides more stable hemodynamics. Remifentanil and dexmedetomidine showed similar sedative effects, with a low incidence of side effects. Although dexmedetomidine and remifentanil sedation scores were similar to the control group, they provide a clinically effective sedation. Low doses of dexmedetomidine and remifentanil can be used safely for sedation during regional anesthesia.