Hemoglobin and Hematocrit Values After Saline Infusion and Tourniquet

Abstract

This study attempted to contribute to standardization of blood testing in sport, and to investigate the effect of artificial dilution with saline. In 10 healthy, physically active males and 3 healthy physically active females hemoglobin (Hb), hematocrit (Ht), and % reticulocytes (%retics) were measured at different time points to look for possible fluctuations during day time, while the subjects had regular coffee breaks and lunch. In 7 of the subjects in a separate experiment 500 ml of saline were infused around 8 am and Hb, Ht, and %retics were measured before and every hour thereafter until 7 hours after infusion. In addition Ht was measured on a hematological analyzer as well as with a centrifuge. In a separate experiment the effect of tourniquet duration on Hb and Ht was studied in 9 of the subjects. The results show that Hb, Ht, and %retics are stable from 8 am to 4 pm, but that infusion of 500 ml of saline induces an acute decrease in Hb and Ht within one hour (Hb decreased from 15.2+/-0.9 g/dl to 14.5+/-1.0 g/dl, and Ht from 45.6+/-2.8 % to 44.0+/-2.5 %). The decline in Hb and Ht was maintained during the 7-hour observation period. Ht values of the same samples measured with a hematological analyzer and a centrifuge were not different. Application of the tourniquet did significantly affect Hb and Ht values only from two minutes, and thereafter Hb and Ht remained stable during the rest of the 5-minute tourniquet. With blood testing in sport these results have to be taken into consideration.

Detection of erythropoietin misuse by the Athlete Biological Passport combined with reticulocyte percentage

“…However, a recent study demonstrated that an optimized instrument calibration of the Sysmex XT‐2000i (which is used by more than 30 of the approximately 35 WADA‐accredited laboratories), lowered the between‐instrument to less than 0.1 %, which is acceptable in anti‐doping. Further, ret% has proven to be stable during both storage and transportation as long as the ABP Operating Guidelines are applied, and it has no diurnal variation …”

“…Further, ret% has proven to be stable during both storage and transportation [31][32][33][34] as long as the ABP Operating Guidelines are applied, and it has no diurnal variation. [35,36] There are little data available on the effect of exercise on ret%. However, few studies have shown that acute exercise has no effect on ret%.…”

ORIGINAL ARTICLE: Are 10 min of seating enough to guarantee stable haemoglobin and haematocrit readings for the athlete’s biological passport?

“…Sampling conditions unrelated to posture are other factors that might considerably influence the results of blood tests. Tourniquet time (Kuipers et al, 2005), sampling site and blood type (Lundvall & Bjerkhoel, 1994) and ambient temperature have all been demonstrated to significantly alter certain blood analytes. In our study, however, these parameters were kept constant (tourniquet time, sampling site, temperature) and are therefore unlikely to have influenced the results.…”

Dynamic contrast enhanced MRI parameters and tumor cellularity in a rat model of cerebral glioma at 7 T

“…If it is assumed that the change in longitudinal relaxation rate ( R 1 = 1/ T 1 ) is proportional to tissue concentration of the CA , the observation equation equivalent to the SM equation is; where Δ R 1a and Δ R 1t refer to the subtraction of the pre‐contrast relaxation rate from its post‐contrast value at artery and tissue, respectively, and Hct is the hematocrit at the level of the microvasculature. In what follows, Hct was assumed to be 0.45 , which may uniformly bias the results presented below, but will not affect the correlations presented.…”