Measurement of blood loss by means of a whole-body counter.

Abstract

In the investigation of patients with hypochromic anaemia the assessment of the part played by gastrointestinal or menstrual blood loss is often extremely difficult. This paper describes a method for the measurement of blood loss over periods of up to three months by means of 59Fe and the simple whole-body counter recently designed in this department (Callender et al., 1966). The principles involved are that 7 to 10 days after the administration of 59Fe all or most of the dose will be incorporated into circulating red cells. In normal males and postmenopausal females the whole-body radioactivity will remain stable and any loss in total body radioactivity must represent loss of blood. The technique was evaluated by studying patients with polycythaemia from whom known quantities of blood were removed by venesection. Its clinical use is illustrated by studies of five patients with hypochromic anaemia.