Determinants of short-term blood pressure variability. Effects of bed rest and sensory deprivation in essential XXXX .

@entity1 @entity551 @entity101 @entity299
In 38 hospitalized @entity1 with uncomplicated essential @entity101 intra-arterial pressure was recorded continuously for 24 hours with the Oxford technique. On the basis of beat by beat analysis, hourly and 24-hour means of mean arterial pressure (MAP) and heart rate (HR) were obtained. The standard deviations and variation coefficients of the hourly means were used as a measure of absolute and relative blood pressure variability respectively. By randomization @entity1 were ambulant during the day (group A; n = 19) or they were restricted to bed (group B). The @entity1 of group B were sensory deprived during the first 4 hours of the blood pressure recording. During the night MAP, HR, and their respective variabilities were similar for both groups. During bed rest MAP was reduced as compared to ambulant values (P less than 0.05), but bed rest had no effect on HR, or on the variability of HR and MAP. @entity551 and HR all declined to nightly values, though MAP did not change. In group B, @entity299 (absolute and relative) was inversely correlated to age, but no relationship between these two parameters was observed in group A. During concomitant sensory deprivation, but not during bed rest alone or during night rest, relative @entity551 was also inversely correlated to age. It is concluded that sensory stimuli have an important effect on HR and on the @entity551 , but not on MAP itself, indicating that to some extent blood pressure and its variability are regulated independently.
