A Comparison of Different Doses Efficacy of Isobaric Ropivacaine 0.5% in Spinal Anesthesia in Cesarean Section

Background: Cesarean delivery is a standard surgical procedure in women. Thus, a practical, affordable, and low-risk anesthetic technique is essential for mother and infant safety. Spinal anesthesia is a popular and efficient technique for anesthesia during cesarean delivery. However, other local anesthesia drugs with negligible side effects should be considered. The most selective medication for this purpose is bupivacaine (marcaine), which creates optimal anesthesia at doses of 10 to 12 mg. Objectives: The most available medicine for spinal anesthesia during cesarean delivery is a 0.5% marine solution. However, ropivacaine for spinal anesthesia can occasionally be accessed as a long-acting amide local anesthetic agent used as an alternative to marcaine during the cesarean delivery. The ropivacaine's advantage over marcaine is its less neurotoxicity and cardiotoxicity, as well as the more stable hemodynamical condition of the patients. So far, no proper therapeutic dose of 0.5% isobaric ropivacaine has been proposed to be used during the cesarean delivery. Any increase in the dose may ensure the block performance, but, by contrast, some side effects may arise, including hypotension, bradycardia, vomiting, and nausea. Herewith, the likelihood of maximum block and most minor side effects was attempted to be assessed at the tiniest doses of this anesthetic agent. Methods: This randomized clinical trial was conducted on C-section candidates. Patients were categorized into three groups receiving 22.5, 25, and 20 mg of the 0.5% isobaric ropivacaine solution. Systolic and diastolic blood pressure, heartbeats, the level of sensational and sympathetic nerve block, duration to reach the maximum motor block, the rate of vasopressors and atropine consumption, rate of vomiting and nausea, the rate of using supplementary drugs, block breakdown, and the patient's satisfaction with the anesthesia were measured and recorded. The collected data were analyzed using IBM SPSS Statistics. Results: No significant difference was found between demographic characteristics. Likewise, there was no significant difference in systolic and diastolic blood pressure, heartbeats, the level of sensational and sympathetic nerve block, duration to reach the maximum motor block, the rate of vasopressors and atropine consumption, rate of vomiting and nausea, and the rate of using supplementary drugs between the three groups. The most significant block breakdown and use of supplementary drugs were found in the first group (20 mg), with a significant difference between the three groups. Conclusions: The three doses used did not result in meaningful differences between the three groups. However, the differences were significant for the block breakdown, with the higher block breakdown and supplementary drug use observed when using 20 mg of the 0.5 ropivacaine solution.