Noninvasive continuous positive airway pressure in elderly cardiogenic pulmonary edema patients

To compare the physiological effects and the clinical efficacy of continuous positive airway pressure (CPAP) vs standard medical treatment in elderly patients (≥75 years) with acute hypoxemic respiratory failure related to cardiogenic pulmonary edema.

A prospective, randomized, concealed, and unblinded study of 89 consecutive patients who were admitted to the emergency departments of one general, and three teaching, hospitals.

Patients were randomly assigned to receive standard medical treatment alone (n=46) or standard medical treatment plus CPAP (n=43).

Improvement in PaO₂/FIO₂ ratio, complications, length of hospital stay, early 48-h and overall mortality, compared between the CPAP and standard treatment groups.

Study groups were comparable with regard to baseline physiological and clinical characteristics (age, sex ratio, autonomy, medical history, cause of pulmonary edema). Within 1 h, noninvasive continuous positive airway pressure led to decreased respiratory rate (respiratory rate, 27±7 vs 35±6 breaths/min; p=0.009), and improved oxygenation (PaO₂/F_IO₂, 306±104 vs 157±71; p=0.004) compared with baseline, whereas no differences were observed within the standard treatment group. Severe complications occurred in 17 patients in the standard treatment group, vs 4 patients in the noninvasive continuous positive airway pressure group (p=0.002). Early 48-h mortality was 7% in the noninvasive continuous positive airway pressure group, compared with 24% in the standard treatment group (p=0.017); however, no sustained benefits were observed during the overall hospital stay.

Noninvasive continuous positive airway pressure promotes early clinical improvement in elderly patients attending emergency departments for a severe pulmonary edema, but only reduces early 48-h mortality.