A comparative study of common techniques used to measure haemolysis in stored red cell concentrates

Background and Objectives There is no standardized method of measuring the parameters for haemolysis determination of red cell concentrate (RCC). Three haemoglobin quantification methods (automated analyser, Harboe and Drabkin’s) and two methods of haematocrit measurement (automated analyser and microcapillary centrifugation) were evaluated for use with RCC. Materials and Methods Twenty stored RCC were assayed for total haemoglobin, supernatant haemoglobin and haematocrit. Results Drabkin’s and Harboe methods were linear (r2 ≥ 0·995) over 0·015–220 g/l haemoglobin. Overestimation by Drabkin’s increased from 0% at 220 g/l to 137% at 0·015 g/l haemoglobin. Harboe values generally stayed within 6% of expected while haematology analyser values had a maximum 11% underestimation above 10 g/l. Analyser total haemoglobin was significantly lower (202 ± 22 g/l) than Drabkin’s (224 ± 24 g/l) and Harboe (222 ± 22 g/l) values. Haematocrit was greater via the analyser (65·7 ± 5·7%) than with microcapillary centrifugation (59·3 ± 5·7%). Conclusions Harboe and Drabkin’s methods are suitable for measuring total haemoglobin and supernatant haemoglobin in RCC. The analyser gave higher haematocrit values (11% on average) than did microcapillary centrifugation.