Imposed Work of Breathing and Breathing Comfort of Nonintubated Volunteers Breathing with Three Portable Ventilators and a Critical Care Ventilator
Abstract
In spontaneous breathing modes, past laboratory work using a lung model indicated portable ventilators as compared to critical care ventilators may increase inspiratory work of breathing. The purpose of this study was to assess the imposed inspiratory work of breathing and breathing comfort of nonintubated healthy volunteers breathing spontaneously through three portable ventilators and a critical care ventilator in a controlled environment. A physiologic theoretical framework was used for the study. With all subjects having continuous positive airway pressure (CPAP) settings of 0 and 5 cm H2O and pressure support ventilation (PSV) settings of 0 and 10 cm H2O, the hypotheses were: 1) Imposed work (WOB1) and pressure-time product (PTP1) with the 7200ae (Mallinckrodt, critical care ventilator) will be less than those in the Achieva (Mallinckrodt) ventilator and LTV 1000 (Pulmonetic) ventilator, which will be less than those of the Univent 754 (Impact) ventilator (WOB1 and PTP1 with 7200ae < Achieva = LTV 1000 <Univent 754); 2) breathing comfort (BC) reported by subjects breathing with the 7200ae will be greater than that with the Achieva and LTV 1000, which will be greater than the Univent 754 (BC with 7200ae> Achieva = LTV 1000 > Univent 754). The study used a randomized, single blind repeated measures design using healthy nonobese subjects (n=16). Measured respiratory parameters were saved to a personal computer and subjects recorded BC on a visual analogue scale that had been previously assessed for validity. Control breathing periods were interposed after each fourth study period; maximum inspiratory pressure was the proxy measure for fatigue.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2001
- Accession Number
- ADA393611
Entities
People
- Paul N. Austin
Organizations
- Air Force Institute of Technology