A Bench Study of Administering Inhaled Nitric Oxide During Intrapulmonary Percussive Ventilation Superimposed With Invasive Mechanical Ventilation

Abstract

Background: Secretion-related atelectasis is a common complication in pediatric mechanical ventilation. Intrapulmonary percussive ventilation (IPV) delivers high-frequency small bursts of gas flow to facilitate pulmonary secretion mobilization and treat secretion-related atelectasis. Inhaled Nitric oxide (iNO) is used to reverse hypoxemia and pulmonary hypertension and potentially reduces ventilator days and use of extracorporeal membrane oxygenation in pediatric mechanical ventilation. A previous bench study demonstrated placement of the NO inject module in line with the sliding Venturi resulted in a ventilator failure and affecting the accuracy of NO delivery during different configurations. We hypothesized that affecting factors of NO delivery and fraction of inhaled oxygen (FIO₂) delivery during IPV superimposing mechanical ventilation are location of NO inject module compared to IPV adaptor and cap on the IPV adaptor.

Methods: We compared iNO delivery using three configurations superimposing IPV with the Gentinge Servo-U ventilator, the Percussionaire IPV-2c, and INOmax DSIR Plus in a lung model. Set NO values were 5, 10, 20, 40, 60, 80 ppm for three configurations. Ventilator settings and lung model values remained consistent throughout the experiments. Delivered NO, NO₂, and FIO₂ were measured. The accuracy of NO delivery was calculated among configurations.

Results: FIO₂ delivery was higher than set FIO₂ when delivering IPV superimposing conventional mechanical ventilation. When the IPV adaptor with cap was followed by the injector module, the accuracy of NO delivery ranged from –90 to –82%. When the injector module was followed by the IPV adaptor without cap, the accuracy of NO delivery ranged from –18 to 0%. When the injector module was followed by the IPV adaptor without cap, the accuracy of NO delivery ranged from –12.5 to 10%. Notably, the configurations with the IPV adaptor followed by the inject module and set NO dose of 80 ppm, the delivered NO values were out of accuracy suggested accuracy (± 10%).

Conclusions: The delivery of NO during IPV superimposing with mechanical ventilation was affected by the injector module and IPV adaptor location. The accuracy of NO delivery was within the suggested range when the injector module was followed by the IPV adaptor.