Exploring the Physiological Effects of 1% Chloroprocaine in Subarachnoid Block: A Comparative Analysis

Abstract

Background: The use of subarachnoid block (SAB), a regional anesthesia technique, has increased with the rise of outpatient surgeries. 1% chloroprocaine, a rapid-onset local anesthetic, is commonly used due to its safety profile and suitability for day care surgeries. However, its specific physiological effects compared to other agents are not well understood. The aim of our study was to compare the physiological effects of 1% chloroprocaine and 0.5% (H) bupivacaine in SAB. Methodology: This randomized controlled study included 80 patients, regardless of gender, of age group 18–60 years, scheduled for elective infraumbilical surgeries. Patients were randomly assigned to two groups: Group A received 0.5% bupivacaine (10.5 mg), and Group B received chloroprocaine (40 mg). Key cardiovascular parameters such as heart rate, blood pressure, and oxygen saturation (SpO2) were monitored. The onset and duration of sensory and motor blockade were also assessed. Results: Hyperbaric bupivacaine administration resulted in a significant decrease in heart rate during the intraoperative period compared to chloroprocaine. However, there was no significant difference in heart rate between the two groups in the postoperative phase. The mean arterial pressure was significantly lower in patients receiving bupivacaine during both the intraoperative and postoperative periods. SpO2 levels did not differ significantly between the two groups. In terms of sensory block, 1% chloroprocaine showed a significantly faster onset, shorter time to readiness for surgery, and quicker regression to the S2 dermatome compared to bupivacaine. Patients receiving bupivacaine experienced a delayed onset, prolonged duration of motor block, and extended recovery time compared to those receiving 1% chloroprocaine. Conclusion: One percent chloroprocaine in SAB maintains cardiovascular function more effectively. It has a minimal impact on SpO2 and offers a rapid onset and shorter duration of sensory and motor blocks without transient neurologic symptoms. Therefore, 1% chloroprocaine is a safe and effective choice for patients undergoing SAB in outpatient surgeries.