Automated RBC Exchange has a greater effect on whole blood viscosity than manual whole blood exchange in adult patients with sickle cell disease

• DOI: 10.1111/vox.12990
• Publication Date: 2020-09-23T12:55:13Z
• Authors: Nassim Ait Abdallah; Philippe Connes; Gaetana Di Liberto; Lucile Offredo; Jean Louis Beaumont; Dehbia Menouche; Karima Debbache; Amna Jebali; Anoosha Habibi; France Pirenne; Frédéric Galacteros; Brigitte Ranque; Pablo Bartolucci
• Keywords: Adult; Male; 03 medical and health sciences; 0302 clinical medicine; Hematocrit; Humans; Female; Anemia, Sickle Cell; Prospective Studies; Blood Viscosity; Erythrocyte Transfusion; 3. Good health

BackgroundBlood transfusion is the cornerstone treatment to reduce the clinical severity of sickle cell disease (SCD), but we need to maintain the haematocrit (Hct) within an acceptable range to avoid a deleterious increase in blood viscosity. The aim of this study was to compare the effects of manual versus automated red blood cell (RBC) Exchange on haematological parameters and blood viscosity.Study design and methodsThis prospective, single‐centre, open nonrandomized observational study included forty‐three sickle cell patients: 12 had automated RBC Exchange and 31 manual RBC Exchange. Samples were collected in EDTA tubes just before and within one hour after the end of the RBC Exchange to measure the haematological parameters and blood viscosity.ResultsBoth automated and manual RBC Exchange decreased haemoglobin S levels and leucocyte and platelet counts, but the decrease was greater for automated RBC Exchange. Manual RBC Exchange caused a significant rise in haematocrit and haemoglobin levels and did not change blood viscosity. In contrast, automated RBC Exchange decreased blood viscosity without any significant change in haematocrit and only a very slight increase in haemoglobin levels. The change in blood viscosity correlated with the modifications of haematocrit and haemoglobin levels, irrespective of the RBC Exchange procedure. When adjusted for the volume of RBC Exchange, the magnitude of change in each biological parameter was not different between the two procedures.ConclusionOur study demonstrates that the automated RBC Exchange provided greater haematological and haemorheological benefits than manual RBC Exchange, mainly because of the higher volume exchanged, suggesting that automated RBC Exchange should be favoured over manual RBC Exchange when possible and indicated.