A COMPUTERS SYSTEM FOR RESPIRATORY PARAMETERS

This paper describes a new method of computing respiratory system parameters. Continuous measurements are made on driving pressure and flow during breathing. Intraesophageal pressure is obtained by a transducer directly in the esophagus. The data are converted to discrete values at a rate of 100 times per second, and then processed by digital computer. A least-mean-square criterion is used to determine compliance and resistance. Calculations are done on the basis of a total breath and separately over inspiration and expiration. Also, compliance is calculated by the two-point method, from pressure and volume at the start and end of inspiration. Statistical analysis of the results show a significantly higher compliance on inspiration than expiration, and a significantly higher resistance on expiration than inspiration. Compliance determined by the two-point method and inspiratory compliance determined by the least-mean-square technique show no significant difference and a high degree of correlation. © 1969.