Stability of Packed Red Blood Cell Units during Mechanical Transport Using a Modern Pneumatic Tube System

Abstract

Background: This study was designed to evaluate the influence of a mechanical transport in a modern pneumatic tube system on the quality of packed red blood cell (RBC) units intended for transfusion. Materials and Methods: At days 0, 7, 14, 21, 28 or 35, 12 units of packed RBCs (freshly prepared, not older than 9 days) were transported in a test pneumatic tube transport system under conditions which were set as close as possible to reality, containing curves, and a partially subterranean course. A second set of 12 units of packed RBCs which were treated identically but for the transport were used as reference. For evaluation of product quality, concentrations of hemoglobin (Hb; spectrophotometric method according to Kahn), lactate dehydrogenase (LDH; optimized method, 25 °C, according to the German Society of Clinical Chemistry), and K⁺ (direct potentiometry) in aliquots of the plasma supernatant obtained after centrifugation were determined. Results: In the plasma of the RBCs subjected to transport, mean elevations in the concentrations of Hb from 200 to 1,160 mg/l, of LDH from 154 to 327 U/l, and of K⁺ from 12 to 62 mmol/l were observed. In the plasma of the reference RBC units, the respective values increased from 179 to 974 mg/l (Hb), from 121 to 348 U/l (LDH), and from 11 to 63 mmol/l (K⁺). Over a period of 7 days, the mean increases (± SD) in the concentrations of Hb, LDH, and K⁺ in the plasma of the transported products were 163 ± 111 mg/l, 33 ± 8 U/l and 10 ± 3 mmol/l, respectively. In the plasma of the reference RBC units these increases amounted to 124 ± 142 mg/l, 43 ± 43 U/l or 10 ± 4 mmol/l. No significant differences were found between transported RBC units and those which had not been transported. Additionally, no significant effects on these hemolysis parameters could be observed when simulating up to 35 loading and unloading processes of the plastic bags filled with the packed RBCs into pneumatic tube containers of 105 mm diameter within 35 days. Conclusions: An increased risk of a loss of quality as a result of the mechanical transport of packed RBC units in a modern pneumatic tube system could not be verified.