Abstract
ABSTRACT: Beside measurement of functional residual capacity (FRC) in ventilated children is impractical. Using a simple technique based on open circuit N2 washout, we measured FRC in ventilated children. The system was evaluated in the laboratory and in patients. Using a mechanical lung, the reproducibility of 200 studies over a range of 100-500 mL at each of four different flow rates (10 determinations at each level) was very high with a mean coefficient of variation of 2.3% (range 0.5-5.1%). Linearity of the integrated N2 signal for volumes of 100-500 mL washed out at different flow rates was excellent (range 7.4-17.9 L/min), r = 0.99. The mean difference between measured and preset mechanical lung volumes was 2.4% (range 0-4.6%). In vivo, reproducibility of six to 10 FRC determinations in each of 30 children gave a mean coefficient of variation of 2.7%. Comparison to the conventional Douglas bag collection method showed a high correlation (r = 0.97). We conclude that this is an easy, highly reproducible, and accurate method for FRC determination suitable to ventilated infants and children.
Similar content being viewed by others
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Sivan, Y., Deakers, T. & Newth, C. An Automated Bedside Method for Measuring Functional Residual Capacity by N2 Washout in Mechanically Ventilated Children. Pediatr Res 28, 446–450 (1990). https://doi.org/10.1203/00006450-199011000-00005
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1203/00006450-199011000-00005
This article is cited by
-
Measurement of end-expiratory lung volume in intubated children without interruption of mechanical ventilation
Intensive Care Medicine (2009)
-
Measurement of lung volume in mechanically ventilated monkeys with an ultrasonic flow meter and the nitrogen washout method
Intensive Care Medicine (2004)
-
Infant lung function testing in the intensive care unit
Intensive Care Medicine (1995)