Alterations in 2-3 Diphosphoglycerate and O2 Hemoglobin Affinity in Patients Undergoing Open-Heart Surgery
Alterations in red blood cell (RBC) 2-3 diphosphoglycerate (2-3 DPG) and hemoglobin affinity for oxygen were studied in 14 patients undergoing heart-lung bypass. RBC 2-3 DPG decreased with institution of bypass and continued to decrease during bypass. The day following heart-lung bypass RBC 2-3 DPG levels returned to normal, but were lower than preoperative control values. In vitro studies demonstrated that a portion of the RBC 2-3 DPG loss is due to circulation of blood through the oxygenator itself. Other factors appear to be involved.
Hemoglobin affinity for oxygen increased during heart-lung bypass in most patients It was found that the increased affinity was less than would be expected relative to the demonstrated RBC 2-3 DPG decrease, and that a progressive decrease in RBC pH partially corrected the alteration in O2 affinity. Our data suggest that other factors are involved in the demonstrated alteration in hemoglobin affinity for O2, and these factors are discussed.
- © 1971 American Heart Association, Inc.