High-flow oxygen delivered via nasal cannula significantly decreased mortality and improved comfort for ICU patients with nonhypercapnic acute hypoxemic respiratory failure, according to a report published online June 4 in the New England Journal of Medicine.
High-flow oxygen didn’t reduce endotracheal 1-month intubation rates, however, as compared with standard oxygen delivery or noninvasive ventilation in a prospective randomized controlled trial comparing the three techniques at 23 ICUs across France and Belgium, said Dr. Jean-Pierre Frat of Centre Hospitalier Universitaire de Poitiers (France) and his associates.
The 2-year study included 310 adults with nonhypercapnic acute hypoxemic respiratory failure, which was usually the result of community-acquired pneumonia. Patients were randomly assigned to receive high-flow oxygen delivered continuously through large-bore nasal prongs (106 patients), standard oxygen therapy delivered continuously through a nonrebreather face mask (94 patients), or noninvasive ventilation delivered through a face mask connected to an ICU ventilator (110 patients).
Intubation rates at 30 days were 38% for high-flow oxygen, 47% for standard oxygen, and 50% for noninvasive ventilation, which are nonsignificant differences. The hazard ratio for death at 90 days was 2.01 for standard oxygen and 2.50 for noninvasive ventilation, as compared with high-flow oxygen. And the number of ventilator-free days at 1 month was significantly greater with high-flow oxygen (24 days) than with either of the other techniques (22 days and 19 days, respectively), the researchers said.
High-flow oxygen also reduced the intensity of respiratory discomfort at 1 hour to a significantly greater degree than did either of the other forms of oxygen delivery and decreased the dyspnea score as well. “These findings might result from the heating and humidification of inspired gases, which prevented thick secretions and subsequent atelectasis, but also from low levels of PEEP [positive end-expiratory pressure] generated by a high gas flow rate and flushing of upper-airway dead space,” they added (N. Engl. J. Med. 2015 June 4 [doi:10.1056/NEJMoa1503326]). Rates of complications were similar among the three study groups.
The study was supported by the French Ministry of Health’s Programme Hospitalier de Recherche Clinique Interregional 2010. Dr. Frat reported receiving travel fees from Fisher & Paykel Healthcare and personal fees from SOS Oxygene. Fisher & Paykel Healthcare donated face masks, heated humidifiers, and cannulas and provided air-oxygen blenders to the participating ICUs.