Related Experiment Videos
Nitric oxide delivery to the lung: a model.
P R Jones1, R H Hooper, N Stopp
1Department of Human Sciences, Loughborough University, Loughborough, Leicestershire and Department of Cardiothoracic Anaesthetics, Glenfield Hospital, Leicester, UK.
European Journal of Anaesthesiology
|April 12, 2000
Summary
Nitric oxide therapy requires careful monitoring. Measured nitric oxide concentrations differ from calculated values due to factors like ventilation rate and infusion site, necessitating direct measurement during treatment.
Area of Science:
- Neonatal respiratory care
- Medical device engineering
Background:
- Dedicated nitric oxide ventilators are available but not widespread.
- Lack of standardized procedures for nitric oxide administration and monitoring with conventional ventilators.
Purpose of the Study:
- To evaluate nitric oxide (NO) delivery using a standard ventilator and a model infant lung.
- To identify factors affecting measured NO concentrations.
- To assess potential contamination and acidification issues.
Main Methods:
- Utilized a time-cycled, pressure-regulated, flow-generating ventilator with a model infant lung.
- Administered NO and measured concentrations at various infusion sites and ventilation settings.
- Analyzed water samples for acid contamination.
Main Results:
- Measured NO concentrations were consistently lower than calculated values.
- Infusion site, minute ventilation, and sampling port significantly impacted NO concentration (P < 0.05).
- Increased minute ventilation led to an exponential decrease in measured NO.
- Infusing NO pre-humidifier reduced acidification without altering delivery.
- Acid contamination was detected in humidifier, water trap, and ventilator outlet.
Conclusions:
- Standard ventilators require careful setup for effective nitric oxide delivery.
- Direct measurement of inspired nitric oxide is crucial for accurate therapeutic dosing.
- Pre-humidifier NO infusion may mitigate acidification issues.