Comparison of two doses of chloroprocaine (20 mg v/s. 30 mg) for spinal anaesthesia in perianal surgery: A prospective observational study (Running title: Chloroprocaine for spinal anaesthesia)

Introduction: The favourable pharmacokinetic properties of 2-chloroprocaine has regained popularity recently as spinal anaesthetic agent because of rapid onset and quick recovery time. The aim of this study was to determine the optimal dose of chloroprocaine for perianal surgeries. Methods: This prospective observational study recruited 30 subjects in each group (group A 20 mg of 1% chloroprocaine and group B 30 mg of 1% chloroprocaine) who underwent elective ambulatory perianal surgeries. Time of unassisted ambulation was considered as primary outcome variable expressed in min. For normally distributed quantitative parameters the mean values were compared between the study groups using independent sample t-test. Categorical outcomes were compared between study groups using Chi square test. Results: Time of unassisted ambulation was 100.50 ± 4.02 min for 20 mg group and 123.17 ± 5.33 min for 30 mg group (p < 0.001). Duration of sensory blockade for 20 mg group was 46.50 ± 5.11 min and for 30 mg group was 76.00 ± 8.14 min (p < 0.001). Duration of motor blockade for 20 mg group was 75.17 ± 7.01 min and for 30 mg group was 99.83 ± 4.25 min (p < 0.001).Conclusion: Chloroprocaine can be used successfully in perianal surgeries. Among the two doses, duration of motor blockade is increased in 30 mg compared to 20 mg, also adequate intraoperative anaesthesia was obtained with 20 mg. Isobaric chloroprocaine 1%, 20 mg is sufficient to achieve adequate intraoperative anaesthesia and leads to earlier discharge.