Initial description of cerebral oximetry measurement in heart failure patients

Cerebral oximetry is a noninvasive technology using near-infrared spectroscopy (NIRS) to monitor regional cerebral tissue oxygen saturation (SctO(2)). NIRS has been widely used for assessing cerebral tissue oxygenation in a variety of populations including the fields of neonatology, anesthesiology, neurology, and cardiac surgery.However, little information has been reported on cerebral oximetry in heart failure (HF) patients. In this observational study, we enrolled 30 patients (15 men) aged 23 to 82 years (mean 67 years) with stage C HF. All patients had New York Heart Association (NYHA) functional class I to III. All patients were on stable HF medical therapy. SctO(2) measurements were recorded from the left and right forehead simultaneously, using FORE-SIGHT cerebral oximeter (CAS Medical Systems Inc, Branford, CT). Feasible associations with SctO(2) risk factors, known to correlate with HF, were recorded. The mean SctO(2) value was 67.4% (range, 47.6%-76.3%), while the mean peripheral tissue saturation (SpO(2)) was 97% (range, 92%-100%). The mean difference between cerebral and peripheral tissue oxygenation (SpO(2)-SctO(2)) was 29.2% (range, 19.2%-51.4%). There was also a significant positive correlation between SctO(2) and mean arterial blood pressure (0.55, P<.01). Statistically significant lower SctO(2) values were observed in patients with diabetes (P=.026; confidence interval [CI], 0.006-0.090) and in patients with dyslipidemia (P=.007; CI, 0.018-0.103). In this initial description of SctO(2) in patients with stage C HF, we noted a wide range of SctO(2) measurements. For most patients, there was a profound SpO(2)-SctO(2) difference, despite near-normal peripheral oxygen saturations. The authors suggest that SctO(2) is a potentially important biomarker to measure in HF patients and may be a useful marker of target organ perfusion.