HEMODYNAMICS, CEREBRAL-CIRCULATION, AND OXYGEN-SATURATION IN CHEYNE-STOKES RESPIRATION

Because cardiovascular disorders and stroke may induce Cheyne-Stokes r espiration, our purpose was to study the interaction among cerebral ac tivity, cerebral circulation, blood pressure, and blood gases during C heyne-Stokes respiration. Ten patients with heart failure or a previou s stroke were investigated during Cheyne-Stokes respiration with recor dings of daytime polysomnography, cerebral blood flow velocity, intra- arterial blood pressure, and intra-arterial oxygen saturation with and without oxygen administration. There were simultaneous changes in wak efulness, cerebral blood flow velocity, and respiration with accompany ing changes in blood pressure and heart rate similar to 10 s later. Ce rebral blood flow velocity, blood pressure, and heart rate had a minim um occurrence in apnea and a maximum occurrence during hyperpnea. The apnea-induced oxygen desaturations were diminished during oxygen admin istration, but the hemodynamic alterations persisted. Oxygen desaturat ions were more severe and occurred earlier according to intraarterial measurements than with finger oximetry. It is not possible to explain Cheyne-Stokes respiration by alterations in blood gases and circulator y time alone. Cheyne-Stokes respiration may be characterized as a stat e of phase-linked cyclic changes in cerebral, respiratory, and cardiov ascular functions probably generated by variations in central nervous activity.