title: Broadband diffuse optical spectroscopy assessment of hemorrhage- and hemoglobin-based blood substitute resuscitation.
abstract: Hemoglobin-based oxygen carriers (HBOCs) are solutions of cell-free hemoglobin (Hb) that have been developed for replacement or augmentation of blood transfusion. It is important to monitor in vivo tissue hemoglobin content, total tissue hemoglobin [THb], oxy- and deoxy-hemoglobin concentrations ([OHb], [RHb]), and tissue oxygen saturation (S(t)O(2)=[OHb][THb]x100%) to evaluate effectiveness of HBOC transfusion. We designed and constructed a broadband diffuse optical spectroscopy (DOS) prototype system to measure bulk tissue absorption and scattering spectra between 650 and 1000 nm capable of accurately determining these tissue hemoglobin component concentrations in vivo. Our purpose was to assess the feasibility of using DOS to optically monitor tissue [OHb], [RHb], S(t)O(2), and total tissue hemoglobin concentration ([THb]=[OHb]+[RHb]) during HBOC infusion using a rabbit hypovolemic shock model. The DOS prototype probe was placed on the shaved inner thigh muscle of the hind leg to assess concentrations of [OHb], [RHb], [THb], as well as S(t)O(2). Hemorrhagic shock was induced in intubated New Zealand white rabbits (N=6) by withdrawing blood via a femoral arterial line to 20% blood loss (10-15 cckg). Hemoglobin glutamer-200 (Hb-200) 1:1 volume resuscitation was administered following the hemorrhage. These values were compared against traditional invasive measurements, serum hemoglobin concentration (sHGB), systemic blood pressure, heart rate, and blood gases. DOS revealed increases of [THb], [OHb], and tissue hemoglobin oxygen saturation after Hb-200 infusion, while blood total hemoglobin values continued did not increase; we speculate, due to hyperosmolality induced hemodilution. DOS enables noninvasive in vivo monitoring of tissue hemoglobin and oxygenation parameters during shock and volume expansion with HBOC and potentially enables the assessment of efficacy of resuscitation efforts using artificial blood substitutes.
authors.affiliation: University of California, Irvine, Beckman Laser Institute and Medical Clinic, 1002 Health Sciences Road East, Irvine, California 92612, USA. jangwl@uci.edu
authors.forename: Jangwoen
authors.initials: J
authors.lastname: Lee
authors.forename: Jae G
authors.initials: JG
authors.lastname: Kim
authors.forename: Sari
authors.initials: S
authors.lastname: Mahon
authors.forename: Bruce J
authors.initials: BJ
authors.lastname: Tromberg
authors.forename: David
authors.initials: D
authors.lastname: Mukai
authors.forename: Kelly
authors.initials: K
authors.lastname: Kreuter
authors.forename: Darin
authors.initials: D
authors.lastname: Saltzman
authors.forename: Renee
authors.initials: R
authors.lastname: Patino
authors.forename: Robert
authors.initials: R
authors.lastname: Goldberg
authors.forename: Matthew
authors.initials: M
authors.lastname: Brenner
mesh_terms: D000818:Animals; D001802:Blood Substitutes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006454:Hemoglobins / Q000032:analysis* / Q000627:therapeutic use*; D006470:Hemorrhage / Q000097:blood* / Q000175:diagnosis / Q000628:therapy*; D008297:Male; D011817:Rabbits; D015203:Reproducibility of Results; D012151:Resuscitation / Q000379:methods*; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation*; D016896:Treatment Outcome
chemical_list: D001802:Blood Substitutes; D006454:Hemoglobins