Evaluation of effect of hip-to-shoulder width ratio on sensory level of spinal anesthesia for urological surgeries: a tertiary care hospital study
Abstract
Background: The sensory level achieved with spinal anesthesia varies among patients and may be influenced by anthropometric factors. Hip-to-shoulder width ratio, as a marker of body habitus, has been hypothesized to affect cephalad spread of intrathecally administered local anesthetics. The objective of the present study was to determine the correlation between hip-to-shoulder width ratio and spinal anesthesia sensory levels in patients undergoing urological surgeries.
Methodology: This descriptive cross-sectional study was conducted at Sindh Institute of Urology and Transplantation over a period of five months from 5th June, 2025 to 10th October, 2025. A total of 111 patients were enrolled through non-probability consecutive sampling. Baseline demographics, anthropometric measurements, and vertebral column length were recorded. Sensory block characteristics and intraoperative complications were assessed. Pearson’s correlation coefficient and chi-square test were applied, with p < 0.05 considered significant.
Results: The mean age of participants was 54.6 ± 10.8 years, with males comprising 82.9%. The mean hip-to-shoulder width ratio was 0.83 ± 0.05. A significant positive correlation was observed between hip-to-shoulder width ratio and both pinprick (r = 0.298, p = 0.002) and temperature sensory block levels (r = 0.312, p = 0.001). BMI also showed a significant association (p = 0.018), while gender and ethnicity did not significantly influence block outcomes. Nausea was the only complication significantly associated with inadequate block (p = 0.042).
Conclusion: Hip-to-shoulder width ratio and BMI are important predictors of spinal anesthesia spread in urological surgeries. Incorporating these parameters into pre-anesthetic assessment may improve block predictability and patient safety.
Keywords: Anthropometry; Body Mass Index; Hip-to-shoulder width ratio; Sensory block; Spinal Anesthesia; Urologic Surgical Procedures
Citation: Naeem N, Abbas MQ, Ghani, Abbas AA, Uddin SW, Kumar V. Evaluation of effect of hip-to-shoulder width ratio on sensory level of spinal anesthesia for urological surgeries: a tertiary care hospital study. Anaesth. pain intensive care 2026;30(6):661-668. DOI: 10.35975/apic.v30i6.3259
Received: May 09, 2025; Revised: October 26, 2025; Accepted: January 01, 2025
