Pilot Validation of a Hemodilution Technique to Estimate Blood Volume in Vivo

The objective of this study is to determine the accuracy of estimating patient blood volume using field-expedient point-of-care measurement of hematocrit before and after hemodilution with a standardized volume of intravenous solution, in comparison to determining patient blood volume by radiodilution. A total of 33 healthy adult male subjects aged 18-35 years will undergo determination of blood volume in a fixed order: first by radiodilution, then by hemodilution. Blood volume as measured by radiodilution will be correlated with blood volume as estimated with hemodilution to assess the potential validity of hemodilution as means of estimating blood volume.