Effect of Storage on Osmotic Fragility in CPDA-1 Stored Blood in Sokoto, Northwestern Nigeria

Abstract

The aim of this study was to investigate the effects of storage on the in vitro osmotic fragility of erythrocytes of humans in a single unit of whole blood. Blood was collected by venepunture from a healthy adult male (70-75 kg) into CPDA-1(450ml) blood bag containing citrate phosphate dextrose as anticoagulant (63ml) and stored in a blood bank maintained at 4°c ± 2°c. The osmotic fragility of the erythrocytes was determined by measuring the release of haemoglobin from blood added to tubes containing serially diluted phosphate buffered saline (pH 7.4). The Blood samples were analyzed on day 1 to day 35 after collection (5 weeks). Increased erythrocyte osmotic fragility was observed at week 3 (p=0.010). The initial haemolysis (>5%) occurred between 0.50% and 0.55% PBS. The mean corpuscular fragility was between 0.35 and 0.45% PBS. Maximum haemolysis occurred in 0.35% PBS. Osmotic fragility was significantly affected by storage (p<0.05). In conclusion, this research showed that there is an increase in the osmotic fragility as donor blood is stored and that the effect is more pronounced from week 3. There is need to maintain the cold chain management of stored donor blood to ensure that the aim of red cell transfusion which is to manage anaemia and increase the oxygen carrying capacity is not compromised.