Prospective Study Evaluating the Association between Time since Scorpion Bite and Spinal Anaesthesia Outcomes

Introduction: The drug mainly used in Spinal Anaesthesia (SA) is Local Anaesthetic (LA) agents. It acts via sodium channel by reversibly inhibiting the nerve transmission. Scorpion venom causes mutation in receptors of sodium channel that leads to LA resistance which results in failed SA. Although, there are few studies and many case reports, which shows direct association of scorpion bite with failed SA, but association of duration since, scorpion bite on outcome of spinal anaesthesia is still not known. Aim: To evaluate the association between time since scorpion bite and multiple bites, an outcome of SA on patients posted for elective lower abdominal and lower limb orthopaedic surgeries. Materials and Methods: This monocentric, prospective, single blind observational study was conducted in the Department of Anaesthesia at Rajarshi Dashrath Autonomous State Medical College (RDASMC), Ayodhya, Uttar Pradesh, India. The duration of the study was two years, from December 2019 to December 2021. A total of 33 patients of either gender or age, between 18-70 years were taken and divided them into three groups of 11 each. Groups were divided on the basis of history of duration since scorpion bite/sting. Group A included patients with history of scorpion bite being less than eight months, group B from eight-14 months and group C more than 14 months. SA was provided with 15 mg 0.5% hyperbaric bupivacaine. The pin prick method and Bromage scale were used to detect the onst of sensory (T1), onset of motor (T2), peak of sensory (T3) and peak of motor block (T4). General Anaesthesia (GA) was given if the SA was found inadequate or failed. The mean +/- Standard Deviation (SD), Student's t-test and Chi-square test were used for statistical analysis of data. Results: The mean age of the study participants of group A was 49.27 years, group B was 50.27 years and group C was 52.18 years. Demographically, all the three groups were comparable. The authors have found that, block failed completely in group A. There was statistically significant increase of T1, T2, T3 and T4 in group B than group C (p<0.05). Statistically significant difference were not found between single scorpion bite and multiple scorpion bite in group B and group C in terms of SA characteristics T1, T2, T3 and T4 ( p>0.05). Conclusion: The present study concludes that, the duration of scorpion bite is a significant factor on the effect of SA in terms of sensory and motor block, but number of stings does not determine the sensory and motor characteristics of SA. The SA should not be given if, the history of scorpion bite is recent (less than eight months).