Trigger performance of five pediatric home ventilators and one ICU ventilator depending on circuit type and system leak in a physical model of the lung

Abstract

Background: The population of children with chronic respiratory failure requiring long-term mechanical ventilation in the home has grown worldwide. The optimal choice from an increasing number of home ventilators commercialized for children is often challenging for the attending physicians. The aim of the present study was to compare the trigger performance of five pediatric bilevel home ventilators and one intensive care unit ventilator depending on circuit type and system leak. Methods: The trigger performances of the ventilators were compared in combination with all compatible circuits using a physical model of the lung with increasing system leak. The flow generator simulated the patient's breathing effort with flow rates of 2.7–6.4 L/min at a frequency of 30 breaths/min. All ventilators were set to deliver 16 cmH2O inspiratory pressure support and 4 cmH2O positive end-expiratory pressure. Results: Trigger thresholds varied from 1.5 to 8 L/min, the pressure rise time to 90% of the maximum from 140 to 385 ms and the trigger work from 0.5 to 6.6 mbar · s. All devices had very short trigger delays below 40 ms. The leak compensation depended on the circuit type. The internal diameter of the circuit had no relevant impact on the trigger performance or the leak compensation. Conclusion: We observed considerable differences in the triggering performance of the evaluated home ventilators depending on leak size and type of circuit. Therefore, an optimal combination of device and circuit should consider the patient's age and condition and the probability of system leak.