Related Experiment Video
Updated: Aug 30, 2026
In Vitro Model of Physiological and Pathological Blood Flow with Application to Investigations of Vascular Cell Remodeling
Published on: November 3, 2015
Changes in red blood cell integrity related to infusion pumps: a comparison of three different pump mechanisms
Bernhard Frey1, Stefan Eber, Markus Weiss
1Department of Intensive Care and Neonatology, University Children's Hospital Zurich, Zurich, Switzerland. Bernhard.Frey@kispi.unizh.ch
Objective:
To study the effects of three different infusion pumps on red blood cell (RBC) integrity.
Setting:
Laboratory.
Interventions:
Transfusion of packed RBCs using three different pumps (syringe pump, conventional peristaltic pump, and a new volumetric pump with shuttle mechanism). Flow rate was set at 20 mL/hr and duration was 2.5 hrs, simulating a neonatal transfusion. Experiments were repeated in each pump with eight different units of packed RBCs.
Measurements And Main Results:
Plasma hemoglobin, potassium, lactate dehydrogenase, bilirubin, and osmotic fragility were assessed before and after transfusion. There was a significant degree of hemolysis in the RBC bags before transfusion (mean +/- sd for plasma hemoglobin, 5.9 +/- 3.0 g/L; potassium, 40.0 +/- 11.8 mmol/L; lactate dehydrogenase, 64 +/- 38 units/L; total bilirubin,: 1.5 +/- 0.8 microM/L). Overall increase between samples before and after transfusion was 12% for plasma hemoglobin (p =.01, paired Student's t -test), 2% for potassium (p =.03), 20% for lactate dehydrogenase (p =.0001), and 47% for total bilirubin (p =.04). Plasma hemoglobin and lactate dehydrogenase changes were significantly influenced by the type of infusion pump (p =.006 and.01, multiple regression analysis). Regarding these two variables, the new volumetric pump was less hemolytic than the other two pumps. The degree of the transfusion-related RBC changes was also significantly and independently influenced by the storage time of the blood bags with plasma hemoglobin, bilirubin, and osmotic fragility changing less in old bags.
Conclusions:
The new pump's shuttle mechanism seems to be less injurious to RBCs compared with a conventional syringe and a peristaltic infusion pump. However, the clinical significance must be related to the hemolytic changes in the RBC units before they are transfused, which are a major source of the overall hemolytic load.
