PT  - JOURNAL ARTICLE
AU  - J. Lukácsovits
AU  - A. Carlucci
AU  - N. Hill
AU  - P. Ceriana
AU  - L. Pisani
AU  - A. Schreiber
AU  - P. Pierucci
AU  - G. Losonczy
AU  - S. Nava
TI  - Physiological changes during low- and high-intensity noninvasive ventilation
AID  - 10.1183/09031936.00056111
DP  - 2012 Apr 01
TA  - European Respiratory Journal
PG  - 869--875
VI  - 39
IP  - 4
4099  - http://erj.ersjournals.com/content/39/4/869.short
4100  - http://erj.ersjournals.com/content/39/4/869.full
SO  - Eur Respir J2012 Apr 01; 39
AB  - In a physiological randomised cross-over study performed in stable hypercapnic chronic obstructive disease patients, we assessed the short-term effects of two settings of noninvasive ventilation. One setting was aimed at maximally reducing arterial carbon dioxide tension (Pa,CO2) (high-intensity (Hi) noninvasive positive pressure ventilation (NPPV)): mean±sd 27.6±2.1 cmH2O of inspiratory positive airway pressure, 4±0 cmH2O of expiratory positive airway pressure and respiratory rate of 22 breaths·min−1. The other was performed according to the usual parameters used in earlier studies (low-intensity (Li)-NPPV): 17.7±1.6 cmH2O of inspiratory positive airway pressure, 4±0 cmH2O of expiratory positive airway pressure and respiratory rate of 12 breaths·min−1. Both modes of ventilation significantly improved gas exchange compared with spontaneous breathing (SB), but to a greater extent using Hi-NPPV (Pa,CO2 59.3±7.5, 55.2±6.9 and 49.4±7.8 mmHg for SB, Li-NPPV and Hi-NPPV, respectively). Similarly, Hi-NPPV induced a greater reduction in the pressure–time product of the diaphragm per minute from 323±149 cmH2O·s·min−1 during SB to 132±139 cmH2O·s·min−1 during Li-NPPV and 40±69 cmH2O·s·min−1 during Hi-NPPV, while in nine out of 15 patients, it completely abolished SB activity. Hi-NPPV also induced a marked reduction in cardiac output (CO) measured noninvasively with a Finometer PRO (Finapres Medical Systems BV, Amsterdam, the Netherlands) compared with Li-NPPV. We conclude that while Hi-NPPV is more effective than Li-NPPV in improving gas exchange and in reducing inspiratory effort, it induces a marked reduction in CO, which needs to be considered when Hi-NPPV is applied to patients with pre-existing cardiac disease.