Comparison of saline consumption between microdiscectomy, uniportal, and biportal endoscopic lumbar disc surgery: A multicenter observational study.

Background Context: The environmental footprint of healthcare has become a growing concern, but the specific resource consumption associated with spine surgery remains largely unexplored. Despite the widespread use of continuous saline irrigation in endoscopic spine surgery, no study has previously compared the volume of saline consumption across different surgical techniques.

Purpose: This study aims to compare saline consumption across three surgical techniques for lumbar disc herniation: classical microdiscectomy (MD), uniportal endoscopy (FE), and biportal endoscopy (UBE).

Study Design/setting: multicenter, international, retrospective observational study.

Patient Sample: This study included 722 patients who underwent lumbar disc herniation surgery between March 2023 and September 2024. Patients were grouped based on the surgical technique used: MD (n = 127), FE (n = 253), and UBE (n = 342).

Outcome Measures: The primary outcome was total saline consumption (Liters). Data collected included also demographic information and surgical duration.

Methods: Statistical analyses included Kruskal-Wallis tests, pairwise comparisons with Bonferroni correction, ROC curve analysis, and a fixed-effects model to assess factors influencing saline consumption.

Results: Saline consumption varied significantly across techniques, with a median (IQR) of 0.08 L (0.02-0.15) for MD, 4.00 L (3.00-6.00) for FE, and 9.00 L (6.00-13.00) for UBE (p < 0.0001) FE technique consumes approximately 50 times more saline than MD, and UBE consume more than 112 times more saline than MD. No significant correlation was found between saline consumption and patient age or BMI.

Conclusion: Endoscopic techniques for lumbar disc herniation require substantially more saline than classical MD. This highlights the need for strategies promoting responsible resource stewardship in spine surgery. Future innovations, such as closed-loop fluid management systems, may help optimize both environmental sustainability and economic efficiency.