Non-invasive ventilation treatment for patients with chronic obstructive pulmonary disease

Abstract

Chronic obstructive pulmonary disease (COPD) affects the lives of millions of patients worldwide. Patients with advanced COPD may require non-invasive ventilation (NIV) to support the resultant deficiencies of the respiratory system. The purpose of this study was to evaluate the effects of varying the continuous positive airway pressure (CPAP) and oxygen supplementation components of NIV on simulated COPD patients by using an established and detailed model of the human respiratory system. The model used in the study simulates features of advanced COPD including the effects on the changes in ventilation control, increases in respiratory dead space and airway resistance, and the acid-base shifts in the blood seen in these patients over time. The results of the study have been compared with and found to be in general agreement with available clinical data. Our results demonstrate that under non-emergency conditions, low levels of oxygen supplementation combined with low levels of CPAP therapy seem to improve hypoxemia and hypercapnia in the model, whereas prolonged high-level CPAP and moderate-to-high levels of oxygen supplementation do not. The authors conclude that such modelling may be useful to help guide beneficial interventions for COPD patients using NIV.

Keywords: decision support systems; lung; medical expert systems; oxygen; patient treatment; physiological models; ventilation.

FIGURE 1

A block diagram of the model used in the study [19].

FIGURE 2

Simulation results in moderate chronic obstructive pulmonary disease (COPD). No continuous positive airway pressure (CPAP) treatment and no oxygen supplementation is used in the experiment. COPD, chronic obstructive pulmonary disease; CPAP, continuous positive airway pressure.

FIGURE 3

Simulation results in advanced COPD with no CPAP and no oxygen supplementation. COPD, chronic obstructive pulmonary disease; CPAP, continuous positive airway pressure.

FIGURE 4

Simulation results in moderate COPD. CPAP = 5 cmH₂O with no oxygen supplementation (F _IO2 = 0.21). COPD, chronic obstructive pulmonary disease; CPAP, continuous positive airway pressure.

FIGURE 5

Simulation results in moderate COPD. CPAP = 5 cmH₂O and F _IO2 = 0.25.

FIGURE 6

Simulation results in advanced COPD. CPAP = 5 cmH₂O and F _IO2 = 0.25. COPD, chronic obstructive pulmonary disease; CPAP, continuous positive airway pressure.

FIGURE 7

Simulation results in advanced COPD. CPAP = 8 cmH₂O and F _IO2 = 0.25. COPD, chronic obstructive pulmonary disease; CPAP, continuous positive airway pressure.