Washing Techniques Compared for Preparation of Autologous Blood Transfusion

Centrifugal cell salvage washing technique is a preferred medical treatment in order to retain lost red blood cells (RBCs) without contaminants. Although this technology very efficiently collects and washes shed blood, it is costly and often impractical or unavailable, especially in middle- or low-income countries.

A team of clinical scientists working with the Sanquin Blood Bank (Amsterdam, the Netherlands) collected a total of nine whole blood units, 500 mL ± 10% in quadruple, and used bottom-and-top collection systems containing 70 mL of citrate-phosphate-dextrose (CPD, Fresenius Kabi, Emmer Compascuum, the Netherlands) at the Sanquin Blood Center to allow their temperatures to adjust to 20 to 24 ℃. The processing of the whole blood with the devices was initiated at around 16 hours after collection.

The laboratory study was designed to compare the centrifugation (autoLog, Medtronic, Eindhoven, the Netherlands), microfiltration (HemoClear BV, Zwolle, The Netherlands) and coarse filtration (Hemafuse, Sisu Global Health, Baltimore, MD, USA) techniques in their ability to remove non-cellular components and recover and concentrate the blood cells. Hematological parameters (cell count, hemoglobin concentration, hematocrit and mean corpuscular volume (MCV)) were obtained using an Advia 2120 hematology analyzer (Siemens Healthcare Nederland BV, Den Haag, the Netherlands).

The hematology team reported that the centrifugal technology confirmed its efficacy to remove potentially harmful solutes and capture red blood cells. The microfiltration technology (HemoClear) reached comparable levels of removal of solutes, with a potential advantage over centrifugal technology in the ability to also recover platelets. The coarse filtration technology (Hemafuse) had no washing capacity but, like the microfiltration technology, has the advantage of recovering platelets. Both filtration-based technologies recovered a significantly greater amount of platelets, with the coarse filtration having the highest recovery of platelets, 92% versus 67% with microfiltration. The mean-free hemoglobin concentration before processing was 11 ± 10 mg/L. The centrifugation procedure significantly increased mean-free hemoglobin concentration to 207 ± 22 mg/L.

The authors concluded that innovative filtration devices represent an alternative to centrifugal technology in the preparation of autologous blood for reinfusion. The HemoClear technology for the first time enables the recovery of washed platelets and red blood cells. Washing of blood cells with saline is necessary to remove non-cellular components and enable safe reinfusion. Both the centrifugation (autoLog) and microfiltration (HemoClear) technologies have a washing feature and effectively reduce the various non-cellular solutes. The study was published on September 30, 2022 in the Journal of Blood Medicine.