The limitations of 113Inm for plasma volume measurement.

Previous authors have claimed that 113InmCl3 is a valid tracer for plasma volume measurement. However, careful measurements in haematologically normal volunteers and in rabbits, using 125I-labelled human serum albumin as a reference tracer, show that the results obtained with 113Inm-chloride, -citrate or -transferrin consistently over-estimate the plasma volume and are probably no better than can be predicted from the height and weight of the subject.