The Science Journal of the American Association for Respiratory Care

2012 OPEN FORUM Abstracts

COMPARISON OF A SINGLE HUMIDIFICATION SYSTEM VERSUS A DUEL HUMIDIFICATION SYSTEM USING THE VDR-4: AN EXPERIMENTAL STUDY.

Clarence Finch, Laura Withers, Quan Nguyen, Joseph L. Nates; Respiratory Care, MD Anderson Cancer Center, Houston, TX

BACKGROUND Airway humidification plays an essential role in the maintenance of ventilatory function. Mucus plugging and bronchial casting has often been contributed to the use of high frequency ventilation. During invasive mechanical ventilation these two relative complications can significantly impair the ventilatory support required for adequate ventilation. The use of high frequency ventilation with the Volumetric Diffusive Respirator (VDR-4) (Percussionaire® Corporation Sandpoint, Idaho) offers a unique mechanism in which to humidify the applied gases being delivered [1]. As a customary approach we have been employing a duel humidifier system method in order to maximize gas hydration. We hypothesized that a circuitry using a two (2) heated pass over humidified systems would enhance the humidity to the tracheal bronchial tree. METHOD After the Institution’s Quality Review Board approval, we conducted an experimental study comparing the effects of one versus two pass-over heated humidification systems (Fisher-Paykel Healthcare, Auckland, New Zealand) with the VDR-4. The tests were performed on a mechanical lung (5600i Pneuview® System, Michigan Instruments Inc., MI) at the same predetermined ventilator settings (FiO2 0.21, Bias Flow 30 L/min, low and high rate 16 and 500/min respectively, peak and end expiratory pressures were 30 and 5 cmH2O respectively). We compared the humidification and temperature output of each configuration at the wye connector using the MFW 300 hygrometer (Cooper®, Middlefield, CT). RESULTS Independent data was recorded every hour for temperature and humidity during a period of twelve (12) hours for the respective configuration. Comparative analysis displayed no statistical difference in the temperature or the relative humidity regardless of using the single or duel humidification approach, (CI 95%) (p=0.575, p=0.174) respectively. CONCLUSION In this study design the use of a duel humidification system in the VDR-4 to further enhance gas hydration to the tracheobronchial architecture proves to be of no benefit and does not warrant added disposable cost. Sponsored Research - None