A59-01 Testing Accuracy of Volume-Targeted Pressure Ventilation in Pediatric-Range Tidal Volumes: A Bench Study of Single Limb Circuit Home Ventilators With Intentional Leaks

Abstract Rationale Volume-targeted pressure ventilation (VT-PV) is increasingly incorporated into home ventilators to ensure a minimal tidal volume (TV) by automatically adjusting inspiratory pressure for goal TV. While adult data demonstrate configuration-dependent accuracy during unintentional leaks, a very limited number of studies have been conducted in the pediatric range, where smaller TV and higher leak-to-TV ratios may amplify algorithmic error. We aimed to quantify the ability of portable ventilators to maintain a certain target TV under controlled low and high intentional leaks with a single-limb passive circuit. Methods Three commercially available portable ventilators were connected to a 0.5 L test lung configured for pediatric mechanics. Each device operated in volume target pressure mode with a target TV of 80 mL, PEEP = 8 cmH2O, PIP min/max:15/30 cmH2O, Respiratory Rate: 20/min, inspiratory time of 0.7 s. Low and high intentional leaks were set by using two different exhalation valves. Expiratory tidal volume (VTe) was measured by a Fleisch pneumotachograph and integrated flow analysis. For each condition, 10 consecutive stable breaths were analyzed. Accuracy was expressed as absolute and percent deviation from the 80 mL target; precision as coefficient of variation (CV %). Results Six test conditions (three ventilators, two leak levels) were analyzed (See Figure 1 below). Under low-leak conditions, mean VTe was 69 mL (Vivo45), 60 mL (EV300), and 67 mL (VOCSN)—each below the 80 mL target by 14 - 25 %. During high-leak conditions, VTe further decreased to 57 mL, 50 mL, and 47 mL, corresponding to − 29 - 41 % deviation from the target. Across all devices, peak inspiratory pressure declined as leak increased, indicating an artificially high VTe estimation by the ventilator in the presence of a higher leak. Figure 1. Mean VTe by Device and Leak Group Conclusions Across all tested conditions, the ventilators under-delivered the target tidal volume, with the Vivo45 demonstrating the greatest stability and the VOCSN exhibiting the largest proportional loss. High leak levels consistently reduced VTe accuracy, underscoring algorithm-specific limitations in leak compensation. Overall, most single-limb passive circuit ventilators-maintained target VTe under low-leak conditions but deviated substantially with higher leaks. These findings emphasize the need to understand circuit design and leak-compensation algorithms when applying volume-targeted modes in pediatric patients with small tidal volumes. Further studies incorporating spontaneous efforts and dynamic leak variations are warranted to guide clinical application. This abstract is funded by: None