title: Calculation of the Residual Blood Volume after Acute, Non-Ongoing Hemorrhage Using Serial Hematocrit Measurements and the Volume of Isotonic Fluid Infused: Theoretical Hypothesis Generating Study.
abstract: Fluid resuscitation, hemostasis, and transfusion is essential in care of hemorrhagic shock. Although estimation of the residual blood volume is crucial, the standard measuring methods are impractical or unsafe. Vital signs, central venous or pulmonary artery pressures are inaccurate. We hypothesized that the residual blood volume for acute, non-ongoing hemorrhage was calculable using serial hematocrit measurements and the volume of isotonic solution infused. Blood volume is the sum of volumes of red blood cells and plasma. For acute, non-ongoing hemorrhage, red blood cell volume would not change. A certain portion of the isotonic fluid would increase plasma volume. Mathematically, we suggest that the residual blood volume after acute, non-ongoing hemorrhage might be calculated as 0·25N/[(Hct1/Hct2)-1], where Hct1 and Hct2 are the initial and subsequent hematocrits, respectively, and N is the volume of isotonic solution infused. In vivo validation and modification is needed before clinical application of this model.
authors.affiliation: Department of Internal Medicine, Kangwon National University School of Medicine, Chuncheon, Korea .
authors.forename: Won Sup
authors.identifier: 0000-0002-4992-4787
authors.initials: WS
authors.lastname: Oh
authors.affiliation: Department of Emergency Medicine, Seoul National University College of Medicine, Seoul, Korea .
authors.forename: Sung-Bin
authors.identifier: 0000-0001-8783-3117
authors.initials: SB
authors.lastname: Chon
mesh_terms: D001810:Blood Volume; D006400:Hematocrit; D006801:Humans; D007552:Isotonic Solutions / Q000627:therapeutic use*; D008962:Models, Theoretical; D012771:Shock, Hemorrhagic / Q000517:prevention & control* / Q000628:therapy*
chemical_list: D007552:Isotonic Solutions
keywords: Blood Volume Determination; Hematocrit; Hemorrhagic Shock; Isotonic Solutions; Traumatic Shock