Abstract

The aim of this study is evaluating the analgesic effect of bupivacaine- dexmedetomidine versus bupivacaine- sufentanil in spinal anesthesia during cesarean section. In this double blinded randomized clinical trial study, 60 parturients of ASA class I and II undergoing elective cesarean section were randomly allocated into one of the two groups: group 1 received 12.5 mg bupivacaine (0.5) + 5 mu g sufentanil and group 2 received 12.5 mg bupivacaine (0.5) + 2.5 mu g dexmedetomidine by 25 Quincke needle, in midline approach and in levels of L3- L4 and L2-L3 in a sitting position. Routine monitoring included ECG, SPO2, HR, and BP was done for each patient. Maternal heart rate and blood pressure were registered before spinal anesthesia. Sensory tests were done assessing the loss of pinprick sensation by a 23G slowed needle every two minutes. The time for sensory blockade to reach T4 level as well as the time for its returning to two lower level (T6) were recorded and the surgery begun when block reached T4 level. Then, the level of anesthesia was checked every ten minutes until the two pinprick block level regressed. The umbilical cord blood samples were taken after delivery to determine the PH and newborn's Apgar scores were recoreded and assessed at minutes of 1 and 5. At the end of surgery, the patient's pain score were determined using visual analog scale (VAS). Common complications of spinal anesthesia including hypotension (SBP <20 initial blood pressure or less than 90 mmHg, bradycardia (HR <20 initial heart rate), nausea, vomiting, pruritus, and respiratory depression (RR <10) were also checked and recorded. Time for sensory block to reach T4, regression to T6 sensorry level and duration of analgesic time and block motor regression time in dexmedetomidine group was longer than sufentanil group and use of ephedrine was more in dexmedetomidine group than sufentanil. Considering pH of umbilical cord blood, two group were not signisicantly different. Two groups were not significantly different in terms of other adverse effects incidence (nausea, vomiting, headache, and pruritus) and Apgar score at minutes of 1 and 5. Based on results, addition of dexmedetomidine to bupivacaine in spinal anesthesia, during cesarean section can be associated with greater success and fewer complications. Sensory and motor block duration is significantly longer in dexmedetomidine group and provide intraoperative and postoperative longer and better analgesia and doesn't have any significant complication for mother and infant