Monitoring of nonlinear respiratory elastance using a multiple linear regression analysis.
The elastic pressure/volume (P/V) curve obtained by the multiple linear regression (MLR) technique using a new model, was compared with the quasi-static P/V points obtained by the rapid airway occlusion technique. Seven infants were studied during mechanical ventilation using a pressure controlled mode. The resistive pressure was subtracted from airway opening pressure, thus determining the elastance related pressure, which was then plotted against the volume to make an MLR-elastance curve. Quasi-static P/V curves of the rapid occlusion technique were constructed by plotting the different inspiratory and expiratory volumes against the corresponding values of the quasi-static airway pressure. The calculated MLR-elastance curves closely fit the experimental quasi-static P/V points obtained by the occlusion technique. There were, however, some discrepancies due to the viscoelastic behaviour of the respiratory system. Although slightly altered by these discrepancies, the multiple linear regression-elastance curves did fit the observed quasi-static pressure/volume characteristics for use in clinical practice. The multiple linear regression technique may prove to be clinically useful by continuous monitoring of respiratory system mechanics during mechanical ventilation.
Muramatsu
K
K
Dept of Pediatrics, Fukuoka Tokushukai Medical Center, Kasuga City, Japan.
Yukitake
K
K
Nakamura
M
M
Matsumoto
I
I
Motohiro
Y
Y
D000403:Airway Resistance / Q000502:physiology*; D004548:Elasticity; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D016014:Linear Models; D008170:Lung Compliance / Q000502:physiology*; D008176:Lung Volume Measurements; D008297:Male; D017711:Nonlinear Dynamics; D012121:Respiration, Artificial / Q000706:statistics & numerical data*; D012127:Respiratory Distress Syndrome, Newborn / Q000503:physiopathology* / Q000628:therapy