Supplementary Material for: Study of Procedural Efficiency in EBUS with Dual versus Single NEEDLEs: Evaluating the Value of a Second Needle in EBUS as it Pertains to Economic and Environmental Impact

Background
Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is the standard for mediastinal and hilar lymph node sampling. Traditionally, a single needle is used, which can lead to procedural downtime while specimens are processed, potentially prolonging anesthesia duration. This study aimed to determine whether using a second needle could expedite the procedure enough to offset its cost.
Methods
In a prospective, single-blind, multi-center, randomized controlled trial, 126 adult patients undergoing EBUS-TBNA were randomized to either one or two needles. The primary outcome was time per needle pass. Secondary outcomes included cost-benefit analysis, diagnostic yield, next-generation sequencing (NGS) sufficiency, and carbon impact.
Results
The two-needle group had significantly faster needle passes (56.2 ± 14.3 vs. 82.1 ± 21.9 seconds; p < 0.001), though total procedure time was not significantly different (22.2 ± 9.1 vs. 24.7 ± 12.5 minutes; p = 0.101). More needle passes were performed in the two-needle group (16.9 ± 6.5 vs. 13.9 ± 6.1; p = 0.004), with no difference in the number of lymph nodes sampled. Diagnostic yield was 96.0% overall, and NGS sufficiency in cancer cases was 93.6%, with no differences between groups.
Interpretation
Using a second needle decreases time per needle pass without changing overall procedure time or compromising diagnostic performance. Although it increases immediate cost a customizable model was developed to help centers determine when the time savings justify the added expense, based on anesthesia cost, needle price, and planned passes per node.