| Title | Theory and Clinical Application of a Digital Nitrogen Washout Computer |
| Author(s) | Tomatsu Shinozaki; John C. Abajian, Jr; Burton S. Tabakin; and John S. Hanson |
| Source | Journal of Applied Physiology, Vol. 21, No. 1, Pages 202-208 |
| Publication Date | 1966 |
| Abstract | The basis for an on-line study of pulmonary nitrogen washout by digital computation techniques is presented. The instrument described produces a semi-logarithmic plot of nitrogen concentration in expired gas versus cumulative alveolar ventilatory volume. Simultaneous measurements of functional residual capacity and main conducting airway volume are also achieved. Application of the method to a model revealed differences between known and determined total and conducting airway volumes of only 2 percent. Determinations in 35 normal subjects and 36 patients with pulmonary disease verified the increased ease and accuracy of performing duplicate studies as compared with conventional methods. Numerous possible sources of error and correction factors are eliminated by the technique, and the on-line inscription of the washout curve greatly facilitates intelligent evaluation of normal and abnormal pulmonary gas distribution. |