Continuous-flow centrifugation hemapheresis in the horse.

The researchers tested a blood separation technique on horses that doesn’t require hydroxyethyl starch, observing how whole blood from 10 horses reacted at different gravitational forces. They found that optimal leukocyte and neutrophil collections occurred at 700 and 700-750 rpm respectively, with peak platelet collection at 1500 rpm. Furthermore, no notable differences were found in the number of leukocytes collected at lower and higher speeds, but notable changes were observed in neutrophils and lymphocytes, while platelet yields increased up to 2000 rpm.

Methodology and Key Findings

• The researchers utilized a blood separation technique known as continuous-flow centrifugation apheresis on horses, and importantly, this method did not rely on hydroxyethyl starch for erythrocyte sedimentation.
• They tested the procedure’s effectiveness and blood separation attributes at varying gravitational forces, specifically ranging from 700 to 1500 rpm, with stable blood withdrawal speed of 100 ml/min.
• The study showed that maximal collection of leukocytes was achieved at 700 rpm, while the best neutrophil collection happened between 700 and 750 rpm.
• Even though neutrophil counts lowered while lymphocyte counts remained stable at higher rpm settings, the researchers could not establish an optimal rpm range for lymphocyte collection.
• The peak of platelet collection happened at 1500 rpm.

Secondary Analysis and Findings

• Likewise, the whole blood response from 5 horses was analyzed at lower (500 to 700 rpm) and higher (1400 to 2200 rpm) centrifuge speeds.
• A consistent withdrawal rate of 100 ml/min and leukocyte collection rate of 3 ml/min were maintained during this analysis.
• The preferred rpm handling was determined and compared with values obtained from the initial 10 horses.
• There were no significant differences in the maximum number of leukocytes collected at both low and high speeds.
• A prominent decrease in neutrophils coupled with the increase in the numbers of lymphocytes was recorded at the higher rpm.
• The efficiency of platelet yields was observed to increase when rpm was maximized up to 2000.