USE OF LEAN BODY WEIGHT VERSUS BODY MASS INDEX FOR CALCULATION OF DOSE OF NONDEPOLARISING MUSCLE RELAXANT FOR PATIENTS UNDERGOING SURGERIES: APP-BASED CALCULATION

Abstract

Background: Precise dosing of non-depolarizing muscle relaxants (NDMRs) is critical to achieve optimal neuromuscular blockade while minimizing risks of prolonged paralysis, residual curarization, and postoperative complications. Body Mass Index (BMI)-based dosing is widely used but does not distinguish between lean body weight (LBW) and fat mass, potentially leading to under- or overdosing, especially in obese or underweight patients. LBW, representing metabolically active tissue, may provide more accurate dosing metrics.

Aim: To compare LBW-based versus BMI-based dosing of NDMRs in surgical patients using an app-based calculation method.M

ethods: In this prospective randomized controlled trial, 60 ASA I–III patients aged 19–65 years undergoing elective surgery at Saveetha Medical College Hospital were randomized into two groups: Group A (LBW-based dosing) and Group B (BMI-based dosing). Dosing was calculated via a custom mobile app integrating patient anthropometry. Baseline demographics, ASA status, NDMR dose, and recovery parameters (train-of-four ratio, extubation readiness) were recorded. Statistical analyses were conducted using SPSS v26, with p<0.05 considered significant.

Results: Groups were comparable in age, sex, ASA status, and comorbidities. LBW-based dosing yielded significantly lower mean drug doses compared to BMI-based dosing (p<0.05), with reduced variability and favorable trends in recovery times. Extubation readiness was achieved earlier in the LBW group, though differences did not reach statistical significance.

Conclusion: LBW-based dosing of NDMRs via app-based calculation may improve dosing precision and perioperative safety compared to BMI-based methods. Integration of technology into anesthesia practice supports individualized dosing and potentially enhances postoperative recovery.