[Spectral analysis of blood pressure in patients with sleep related respiratory disorders]

Spectral analysis is a helpful tool to investigate the interaction of blood pressure, respiration and sleep (6). The analysis of systolic pressure is most suitable for the documentation of compressed spectral arrays, since there are less disturbances than from the heart rate. The method used in this study allows the discrimination and quantitative evaluation of periodic blood pressure oscillations associated with apneic and breathing phases. It could be shown that the amplitude of the pulsus paradoxus increases during episodes of obstructive snoring. Heavy snore showed rather stable respiratory frequencies during the whole night which was not found that distinctly in patients with obstructive sleep apnea. The parallel analysis of blood pressure variations and sleep phases revealed different mechanisms in the regulation of REM- and non-REM sleep which transfer sleep related breathing disorders from a periodic pattern in a nonperiodic one and hereby influence at least the regulation of heart rate and blood pressure.