Study objective: Hemoglobin-based oxygen carrier 201 (HBOC-201) is a polymerized hemoglobin of bovine origin being developed for use in hemorrhage during surgery or trauma. Pulse oximetry is commonly used in clinical practice to assess percent saturation of hemoglobin (Spo2). The ability to measure Spo2 in the presence of HBOC-201 will be important for the use of this compound in patient care.
Methods: We carried out a randomized, single-blind, placebo-controlled study at the Upjohn Research Clinics in Kalamazoo, Michigan, with normal, healthy adult men and women as subjects. The members of four groups of adult subjects (N=24) each received 45 g of HBOC-201 (nine each, men and women) or a control solution (Ringer's lactate) (three each, men and women). Each subject underwent phlebotomy (about 15% of estimated blood volume) followed by 3:1 hemodilution with Ringer's lactate and then either HBOC-201 or control solution. An indwelling arterial catheter in the radial artery was used for serial arterial blood gas sampling. Arterial blood gas measurements were made with a cooximeter (Instrumentation Laboratories). Fingertip pulse oximetry was used (Criticare 504-US; Criticare, Incorporated). Paired pulse oximetry and arterial blood gas sampling were made serially (at approximately hourly intervals) over 24 hours.
Results: The mean +/- SEM difference for Spo2 for arterial blood gas analysis compared with the pulse oximetry reading in the presence of HBOC-201 was 1.1% +/- 0.75%; in controls it was .1% +/- 0.64% (P<.001) for each) over the 24 hours after dosing. This relationship was constant despite increased concentrations of plasma hemoglobin (between 1 and 2g/dl [10 to 20 g/L]) in the HBOC-201 groups.
Conclusion: Accurate determinations of Spo2 can be made with pulse oximetry in subjects given HBOC-201 over the normal range of Spo2.