Comparison Of Discontinuous Blood-Pressure Monitoring (Spacelabs-90207) With Intraarterial Recordings In Sleep-Apnea Patients - Limitations Of The Method

The method of ambulatory blood pressure monitoring (ABPM) is widely used in the diagnosis and treatment-control of arterial hypertension. Patients with sleep related breathing disorders (SRBD) suffer very often from arterial hypertension and altered circadian blood pressure (bp) profile. Even in these patients, the ABPM is used to estimate the cardiovascular risk. The aim of this study was to compare intraarterial blood pressure recordings with DBPR (Spacelabs 90207) in 20 patients with mild to moderate arterial hypertension and mild to moderate SRBD. Our first results of whole-night measurements show that the mean arterial pressure seems to be the most reliable value (mean difference Spacelabs P-art: +1,7 mmHg, correlation: r = 0.74). In contrast, the systolic bp is systematically underestimated (mean: -17.5 mmHg, p < 0.001, r = 0.85) while the diastole value is systematically overestimated (mean: +9.3 mmHg, p < 0.001, r = 0.60) by Spacelabs. Our data show that neither systolic nor diastolic bp of Spacelabs measurement reflect the real cardiovascular load. In future, further reliable non-invasive continuous measurement should be accomplished to assess the bp undependent on body position in patients with SRBD during the night.