Measurement of functional residual capacity by nitrogen washout during partial ventilatory support

Abstract

This study suggests that, using corrections for gas viscosity, sampling delay time, and re-inspired nitrogen, FRC can be determined with good repeatability in patients and good accuracy in a lung model during partial ventilatory support.

Proportional assist versus pressure support ventilation in patients with acute respiratory failure: Cardiorespiratory responses to artificially increased ventilatory demand*

“…For the calculation of EELV, the multiple breath nitrogen washout method was used as described in detail previously (24,25). Mean values of two consecutive EELV determinations were used for the analysis; the coefficient of variation was 6.5%.…”

The Effect of Alveolar Dead Space on the Measurement of End-Expiratory Lung Volume by Modified Nitrogen Wash-Out/Wash-In in Lavage-Induced Lung Injury

“…As a multiple breath wash-out method, the volume that is measured by the modified EELV-N 2 method is in fact "accessible pulmonary gas volume." 12 However, the difference between the traditional nitrogen wash-out/wash-in method 28,29 and the modified method lies in how the volume of nitrogen is measured. In the modified method, nitrogen is not measured using a mass spectrometer technique, but is calculated by determining V O 2 and V CO 2 .…”

Functional residual capacity tool: A practical method to assess lung volume changes during pulmonary complications in mechanically ventilated patients

“…Earlier studies have proven that FRC can be determined with good repeatability in patients during partial ventilatory support. [8]…”