MedicineCell BiologyHematologyCell PhysiologyHematology PhysiologyTransfusion MedicineLongevityRed Blood Cell PhysiologyRed Blood Cell TransfusionErythrocyte LifespanRed Blood Cell AgingRed Blood Cell LifespanRed Cell Survival
<h3>To the Editor:—</h3> In a recent editorial on the longevity of the erythrocyte (The Journal, April 21, p. 1304) are quoted the results of studies made by Escobar and Baldwin, who found the life of the red blood cell to be from eighteen to thirty days. The method used by Escobar and Baldwin and also the other methods mentioned in the editorial are indirect and therefore may yield inconclusive results. There is a simple method for determining the life of an erythrocyte by means of which accurate results can be obtained but which is not mentioned in the editorial; namely, by tracing the fate of transfused blood cells. In the editorial, the following statement was made: "Unfortunately, one cannot earmark an erythrocyte and follow its fate in the circulation or in some secluded organ." This is not entirely true, for there are certain natural "earmarks" by which the transfused red