Objective: To compare the acute effects of oxygen therapy and nasal continuous positive airway pressure (nCPAP) therapy on Cheyne-Stokes respiration (CSR) in patients with stable chronic congestive heart failure (CHF).
Methods: Prior to the study, all patients had an echocardiogram performed to measure the left ventricular ejection fraction (LVEF). In addition, all patients had an initial sleep study to identify the presence of CSR. Those patients identified as having CSR were randomized to a night on 2 L/min oxygen therapy, a night on 4 L/min oxygen therapy (by nasal cannula) and another night on nCPAP therapy [mean pressure (9.1 +/- 1.1) cm H2O].
Results: Twenty-six patients stable CHF, with a mean age of 64.1 +/- 6.8, and a mean LVEF of (27.1 +/- 5.8)%, were studied, of whom 14 (53.8%) had CSR during their initial sleep study. The 14 patients had an average apnea-hypopnea index (AHI) of 34.9 +/- 8.2 events per hour, an average apnea-hypopnea length of (20.6 +/- 3.2) s, mean cycle length (74.8 +/- 21.3) s, circulation time (25.6 +/- 4.4) s, the lowest oxygen saturation during the night (76.2 +/- 4.7)%, the periods of time with a oxygen saturation of < 90% of total sleep time (20.9 +/- 8.6)%. When compared with baseline measurements, both oxygen therapy (2 L/min or 4 L/min) and nCPAP therapy significantly decreased the AHI, with 4 L/min oxygen therapy and nCPAP therapy producing the better results, with no significant difference between these two therapies. All three forms of treatment significantly increased the lowest oxygen saturation during the night to a similar extent. The mean percent time the oxygen saturation was < 90% also improved with all interventions, with 4 L/min O(2) producing the best results. In addition, 2 L/min or 4 L/min oxygen therapy and nCPAP produced similar improvements in total sleep time and sleep efficiency. When compared with baseline measurements, the apnea-hypopnea length, cycle length, and circulation time did not significantly change with either oxygen therapy or nasal CPAP therapy.
Conclusion: CSR occurs frequently in patients with stable CHF. Both higher concentration oxygen and nCPAP can be used as therapeutic strategies in CHF patients with CSR.