The application of biphasic extrathoracic cuirass-assisted ventilation in normal subjects wearing chemical–biological–radiological–nuclear (CBRN) gas masks

Objective: Mobile RTX (MRTX), a portable light-weighted ventilator, provides noninvasive respiratory support using biphasic extrathoracic cuirass-assisted ventilation. Despite the effectiveness of chemical–biological–radiological–nuclear (CBRN) gas masks, they cause respiratory loading as a result of added dead space and resistance. This prospective comparative pilot study was conducted to investigate the safety and efficacy of assisted ventilation provided by MRTX in healthy adult volunteers wearing CBRN gas masks at rest. Methods: Cardiorespiratory parame-ters were monitored in 11 healthy adult volunteers breathing spontaneously or with assisted ventilation provided by MRTX, freely or with the mask on. Comparisons were made by single-factor analysis of variance. Results: AV significantly increased minute ventilation (p < 0.001). MRTX increased minute ventilation by 6.4 L/min (mean, 95% confidence interval: 3.1, 9.8; p < 0.005) and by 4.7 L/min (1.8, 7.5; p < 0.01) during spontaneous breathing and with the mask on, respectively. Simultaneously, end-tidal carbon dioxide partial pressure decreased by 3.6 mmHg (2.2, 5.1; p < 0.001) and by 6.5 mmHg (3.8, 9.1; p < 0.001). Discussion: Biphasic extrathoracic cuirass assisted ventilation provided by MRTX is safe and effective in supporting adequate needs at rest even when wearing protective masks. MRTX should be further assessed as a possible adjunct to currently used field ventilation in CBRN scenarios.