2006 OPEN FORUM Abstracts
Performance of a Novel Humidification Device in Mechanical Ventilation
N.H. Tiffin, BSc RRT MSA1, L.A.
Weinstein, MS1, D.E. Sunstein, SB2,
T.Q. Tran, BS1 and J.B. Taylor, BFA3. 1Pari
Respiratory Equipment, Midlothian, VA, United States; 2Sunrise Labs,
Auburn, NH, United States and 3Farm Design, Hollis, NH, United
Background: A novel active humidification system has been developed which can heat and humidify dry therapeutic gases. This study measures the ability of this in-line humidification device (PARI HydratePari Respiratory Equipment, Midlothian , VA ) to heat and humidify gas during mechanical ventilation. The new technology (C-ForcePari Respiratory Equipment) produces water vapor in a pressurized stream from an in-line, small device placed proximal to the patient. A controller allows precise water introduction into the bottom of a ceramic disk. A heating plate on the top of the disk vaporizes the water inside the ceramic and the resultant vapor stream is directed into the gas flow. Energy efficiency is over 90% and there are no moving parts in the disk.
Method: We used a Puritan Bennett 7200 mechanical ventilator with a rate of 15 bpm, Vt=700 mL, PEEP=10 cm H2O and descending waveform setting. Our test lung (Quick Lung, Ingmar Medical, Pittsburg, PA, USA) was set to normal lung settings to simulate Cp=0.2 L/cm H2O and Ra=5 cm H2O/L/s. The device was inserted into the ventilator circuit 6wyewyeoC.
Results: Average RH after 5 minutes was 84.5 + 8.1% and after 20 minutes was 90.1 + 2.8%. (average + stand deviation). Average temperature over the span of testing was 37.3 + 0.6 oC with a maximum of 38.7oC. The inspiratory line of the circuit remained dry from the ventilator to the distal outlet of the device. No water was found in the 6wye
Conclusions: Minimum recommended absolute humidity for mechanical ventilation is 30 mg H2O/L at 30°C and recommended levels of absolute humidity between 36 mg/L to 40 mg/L. The Pari Hydrate, at an average temperature of 37.3oC and 90.1% RH, is capable of heating and humidifying dry oxygen flow up to 40 L/min to over 35oC and over 90% relative humidity. Application to mechanical ventilation is possible. The device effectively heats the ventilator gas to within a narrow and clinically safe range of temperature and can humidify dry oxygen during mechanical ventilation to recommended levels at the patient wyeinspiratory line of the circuit dry.