title: Influence of blood-taking procedure on the heart function of blood donors.
abstract: The systolic time intervals and heart rate were studied in 11 blood-donors aged between 20 and 48 years by a non-invasive technique before and after the usual blood-taking procedure. No statistically significant difference was found between values determined before and after the procedure. A significant correlation (r = 0.76) was demonstrated between percent changes of pre-ejection period/left ventricular ejection time (PEP/LVET)-ratio and withdrawn volume of blood (450 ml) X time (min)-1  X bodyweight (kg)-1. No correlation was found between percent changes of PEP/LVET-ratio and withdrawn volume of blood X time-1, nor between percent changes of PEP/LVET-ratio and withdrawn volume of blood X percentage of circulatory volume removed-1. It is suggested that the blood-taking time (in minutes) should not be shorter than the quotient: donated volume of blood (ml) X bodyweight (kg)-1 if a negative influence of withdrawal procedure on left ventricular function is to be avoided. Mechanisms contributing to circulatory stability during reduction of blood volume are briefly discussed.
mesh_terms: D000328:Adult; D001782:Blood Donors; D001800:Blood Specimen Collection; D001810:Blood Volume; D001835:Body Weight; D002302:Cardiac Output; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D013599:Systole; D013997:Time Factors; D016276:Ventricular Function