Changes in respiratory and circulatory functions during sequential invasive-noninvasive mechanical ventilation.

OBJECTIVE: To investigate the changes in respiratory and circulatory functions in chronic obstructive pulmonary disease (COPD) patients during sequential invasive-noninvasive mechanical ventilation therapy, and evaluate the effects of this new technique.

METHODS: Twelve COPD patients with type II respiratory failure due to severe pulmonary infection were ventilated through an endotracheal tube. When the pulmonary infection control window (PIC-Window) occurred, the patients were extubated and were ventilated with a facial mask using pressure support ventilation combined with positive end-expiratory pressure. The parameters of hemodynamics, oxygen dynamics, and esophageal pressure were measured at the PIC-Window during invasive mechanical ventilation, one hour after oxygen therapy via a naso-tube, and three hours after non-invasive mechanical ventilation.

RESULTS: The variation in esophageal pressure was 20.0 +/- 6 cmH(2)O during naso-tube oxygen therapy, and this variation was higher than that during non-invasive mechanical ventilation (10 +/- 6 cmH(2)O, P < 0.01). The changes in respiratory and circulatory parameters were not significantly different between invasive mechanical ventilation and noninvasive mechanical ventilation (P > 0.05).

CONCLUSIONS: The respiratory and circulatory functions of COPD patients remained stable during sequential invasive-noninvasive mechanical ventilation therapy using PIC-Window as a switch point for early extubation. The COPD patients can tolerated the transition from invasive mechanical ventilation to noninvasive mechanical ventilation.