The circadian rhythm of the colloid osmotic pressure of the blood
Graf, H.; Retzke, U.
Anaesthesiologie und Reanimation 18(2): 40-43
1993
ISSN/ISBN: 0323-4983 PMID: 8397669 Document Number: 418028
In 29 normotensive nonpregnant women, the circadian rhythm of the colloid-osmotic (oncotic) pressure (COP) was estimated. On average the COP was 25.3 mmHg (3.34 kPa). Around this value (= 100%) the daily oscillation was 13.5% with an interindividual variation of between 28.1 and 4.3%. A stable sinusoidal daily rhythm occurred with the lowest values in the night and the highest values in the afternoon. Changes in arterial blood pressure and of the permeability of capillaries depending on the time of day are discussed as the main reason for this circadian rhythm. For COP estimations in clinical routine proofs should be taken at about 8.00 a.m. since these values correspond most closely to the daily average.