St. Hiippala et al., HEMOSTATIC FACTORS AND REPLACEMENT OF MAJOR BLOOD-LOSS WITH PLASMA-POOR RED-CELL CONCENTRATES, Anesthesia and analgesia, 81(2), 1995, pp. 360-365
The purpose of this study was to assess the change of platelet and fib
rinogen concentrations and the change of activities of prothrombin and
factors V and VII when major surgical blood loss was replaced with pl
asma-poor red cell concentrates (RCCs) and colloid plasma substitutes.
Sixty patients were studied. The average blood loss was 65% +/- 41% o
f the calculated blood volume (CBV). Blood loss was monitored carefull
y and replaced without delay to ensure stable blood volume. Blood samp
les were obtained at the induction of anesthesia and at the end of the
recovery room period, or before the patient was given fresh frozen pl
asma. In addition, a platelet count was determined after each 20% bloo
d loss. The results were converted to relative values, and simple Line
ar regression with logarithmic transformation was applied. The initial
platelet concentration was 257 +/- 89 x 10(3)/mm(3) and the extrapola
tion of the regression line intercepted the critical level of 50 x 10(
3)/mm(3) at 230% (confidence interval 169%-294%) blood loss. The initi
al fibrinogen concentration was 3.7 +/- 1.1 g/L and the hemostatically
significant level of 1.0 g/L was already reached at 142% (117%-169%)
blood loss (r(2) = 0.90). Activities of prothrombin and coagulation fa
ctors V and VII reached their critical levels at 201% (160%-244%), 229
% (167%-300%), and 236% (198%-277%) blood loss, respectively. We concl
ude that deficiency of fibrinogen develops earlier than any other hemo
static abnormality when plasma-poor RCCs are used for the replacement
of major blood loss.