Kw. Grathwohl et al., DOES HEMODILUTION EXIST - EFFECTS OF SALINE INFUSION ON HEMATOLOGIC PARAMETERS IN EUVOLEMIC SUBJECTS, Southern medical journal, 89(1), 1996, pp. 51-55
The effects of intravenous fluids on hematocrit are debated. We sought
to determine whether maintenance or bolus fluid therapy causes a sign
ificant change in the hematocrit and other hematologic parameters incl
uded in the complete blood count. Nine subjects completed a randomized
three-period crossover designed trial in which they were given no flu
id, maintenance fluid, or a bolus of fluid followed by maintenance flu
id. We measured complete blood counts at baseline, 1 hour, 4 hours, an
d 8 hours. In the bolus fluid trial, the hemoglobin and hematocrit val
ues (mean +/- SEM) decreased by a maximum of 1.5 +/- 0.1 g/dL and 4.1
+/- 0.3% at 1 hour. There was no difference in hemoglobin or hematocri
t during the no fluid or maintenance fluid treatments. No significant
changes occurred in white blood cell or platelet counts. We demonstrat
ed that maintenance fluid infusions do not significantly alter the com
plete blood count. Saline bolus is associated with a significant decre
ase in hemoglobin and hematocrit, but these parameters trend toward ba
seline over time.