Correlation of Vertebral Column Length and Abdominal Circumference with Subarachnoid Block Characteristics of Hyperbaric Ropivacaine for Infraumbilical Surgeries: A Single-arm Interventional Study

Abstract

Introduction: Spinal anaesthesia is a neuraxial anaesthesia technique used for lower abdominal and lower limb surgeries. The spread of the intrathecally administered local anaesthetic drug during spinal anaesthesia may be affected by many factors. Aim: To evaluate the correlation between abdominal girth and vertebral column length with the intrathecal spread of hyperbaric ropivacaine. Materials and Methods: This prospective single-arm interventional study was conducted in the Department of Anaesthesia at Pt. BDS PGIMS Rohtak, Haryana, India from November 2022 to March 2024. A total of 100 patients of either sex, aged between 20 and 60 years, scheduled for infraumbilical surgeries under Subarachnoid Block (SAB), were included in this single-arm intervention study. Abdominal girth and vertebral column length of the enrolled patients were measured in sitting position. SAB was administered with 3 mL of 0.75% hyperbaric ropivacaine. Sensory and motor block assessments were conducted after the block. The highest sensory block level, time taken to achieve the highest sensory block level and Bromage score of 3, the time taken for two-segment regression and regression to Bromage score of 0 were recorded. Haemodynamic parameters and any complications were noted. Data was compiled and the correlation of vertebral column length and abdominal circumference with sensory and motor block characteristics was analysed at the end of the study. The Pearson’s correlation test was used to determine correlation and a p-value of 0.05). Conclusion: Patients with larger abdominal circumference have more cephalad spread of intrathecal ropivacaine in non obstetric patients undergoing infraumbilical surgeries. However, the present study found no correlation between vertebral column length and any SAB characteristics.

Keywords

• local anaesthetic spread
• motor block
• sensory block