PURPOSE: Whereas numerous studies have demonstrated a high prevalence of obstructive and central sleep apnea in patients with stable congestive heart failure, little data exist regarding the frequency and severity of sleep disordered breathing in acutely decompensated patients who require hospital admission. This study evaluates the prevalence of nocturnal desaturations in these patients.
METHODS: Adult patients admitted to a non ICU setting with a primary diagnosis of congestive heart failure were prospectively enrolled within 72 hours of admission. Patients with a previous diagnosis of sleep apnea were excluded. After informed consent, patients were monitored that evening with continuous trend oximetry utilizing either a Nelcor Symphony 3000 or a Nonin Medical 3100 WristOx unit with signal average sampling time of 4 seconds or less. The flow rate of any oxygen supplementation was determined by the attending physician based on usual standards of care and protocols. Data from the oximeter did not influence clinical care during the night of testing.
RESULTS: Forty-nine patients were enrolled, 24 male and 25 female with an average age of 70.3 (range 28–94 years of age). Eleven were black, 1 Hispanic, and 37 white. The mean BMI was 28.9 (range 19.4–50.9). Average supplemental oxygen administered was 1.8 LPM.9 patients (18%) spent more than 30 minutes of the night with saturations below 89%. 11 patients (22%) had a minimum saturation below 79% and 6 patients (12%) had a minimum saturation below 69%. Neither body mass index, serum creatinine, hemoglobin, brain natriuretic peptide level, diuretic dose, nor level of supplemental oxygen correlated well with desaturation indices.
CONCLUSION: Clinically significant nocturnal desaturations occur in a substantial percentage of patients admitted with acute congestive heart failure despite the use of supplemental oxygen.
CLINICAL IMPLICATIONS: Since oxygen requirements in patients admitted with congestive heart failure are typically titrated based on waking oximetry levels, in some patients disordered breathing events in sleep produce clinically significant desaturations. Improved recognition of this occurrence may permit improved clinical outcomes for this group of patients.
DISCLOSURE: Peter Whitesell, None.