Aims
This study will look to address the primary research question: does the wash solution used during cell salvage affect the incidence of haemolysis and blood damage? We aim to determine whether the wash solution (plasmalyte versus normal saline) used during the cell salvage process has an effect on markers of human blood quality by measuring these parameters pre- and post- processing using the two solutions.
Significance
Blood, in particular red cells, are an essential but expensive and limited product used in healthcare. The issues with the use of donated stored blood are many and autologous transfusion is preferred in most clinical cases where it is feasible. Cell salvage is a well-established method of autologous blood processing, in which the patient’s own blood is collected, washed and reinfused if required during surgical procedures. As part of the Perioperative Patient Blood Management Guidelines issued by the National Blood Authority, cell salvage is recommended for use in adult patients undergoing surgery in which substantial blood loss is anticipated (Grade C recommendation). The investigators have identified that there is a distinct lack of evidence surrounding cell salvage best practice and in particular, there is uncertainty as to the optimal wash solution that should be used for red cell processing and how the wash solution used could potentially be impacting the quality of red cells recovered during processing. Poor quality red cells recovered from cell salvage are stiffer (less deformable) and have the potential to become haemolysed and therefore have a reduction in their oxygen carrying capacity, have reduced nitric oxide bioavailability and can cause harm to organ systems such as the kidneys. The investigators aim to investigate this issue and identify the optimal wash solution for cell salvage that can be used in clinical practice to improve cell salvage quality.
Hypothesis
We propose that the use of plasmalyte as the wash solution during cell salvage will have a superior effect on blood quality (as assessed using a comprehensive panel of blood assays) when used during cell salvage, compared to normal saline.
Objectives
We aim to identify if the wash solution used during cell salvage has deleterious effects on cell salvage blood quality, through a comprehensive assessment of blood rheology.
Methods
A crossover in-vitro study will be performed with the recruitment of 20 healthy (18 – 70-year-old) adult blood donors who are without any pathology and or medications that may alter blood quality. Blood will be collected by our chief investigators from healthy volunteers. A baseline blood sample will be taken for analysis of the below listed blood quality parameters and then immediately divided into two aliquots: one for processing using standard saline solution, while the second will be processed using plasmalyte. This will replicate the washing of blood during surgery. The LivaNova Xtra autotransfusion machine (Sorin Group Italia S.r.l., London, UK) with a 55mL bowl and the optimal default setting will be used. Following blood processing, blood quality will be assessed at Griffith University and will examine; 1) Basic haematology, 2) Cell fragmentation, 3) Plasma free haemoglobin, 4) Cell mechanical assessment, 5) Morphological assessment, 6) Cell density distribution assessment. The primary outcome measured will be plasma free haemoglobin. Secondary outcomes measured will include an additional analysis of blood haemolysis, haematology, osmolarity, electrolytes, morphology and cell mechanical measurements. Data will be coded by investigators and stored anonymously in a pooled spreadsheet.
Benefits of research
We aim to identify if plasmalyte is a superior cell salvage wash solution compared to normal saline that limits any impact red cell processing has on cell salvage blood quality. In future, we hope the results of this study can be translated and investigated further in a clinical setting at our centre if the hypothesis is accepted. The results of this study could influence future clinical practice by identifying a superior cell salvage wash solution used for processing blood.
Dr Elizabeth Forrest, Princess Alexandra Hospital and Griffith University, Queensland.
Dr Alistair Kan, Gold Coast University Hospital and Griffith University, Queensland.
Associate Professor Michael Simmonds, Griffith University, Queensland.
The project was awarded A$18,426 funding through the ANZCA research grants program for 2024.