Use of clinical data and acceleration profiles to validate pneumatic transportation systems

Abstract

BackgroundModern pneumatic transportation systems (PTSs) are widely used in hospitals for rapid blood sample transportation. The use of PTS may affect sample integrity. Impact on sample integrity in relation to hemolysis and platelet assays was investigated and also, we wish to outline a process-based and outcome-based validation model for this preanalytical component.MethodsThe effect of PTS was evaluated by drawing duplicate blood samples from healthy volunteers, one sent by PTS and the other transported manually to the core laboratory. Markers of hemolysis (potassium, lactate dehydrogenase [LD] and hemolysis index [HI]) and platelet function and activation were assessed. Historic laboratory test results of hemolysis markers measured before and after implementation of PTS were compared. Furthermore, acceleration profiles during PTS and manual transportation were obtained from a mini g logger in a sample tube.ResultsHand-carried samples experienced a maximum peak acceleration of 5 g, while peaks at almost 15 g were observed for PTS. No differences were detected in results of potassium, LD, platelet function and activation between PTS and manual transport. Using past laboratory data, differences in potassium and LD significantly differed before and after PTS installation for all three lines evaluated. However, these estimated differences were not clinically significant.ConclusionsIn this study, we found no evidence of PTS-induced hemolysis or impact on platelet function or activation assays. Further, we did not find any clinically significant changes indicating an acceleration-dependent impact on blood sample quality. Quality assurance of PTS can be performed by surveilling outcome markers such as HI, potassium and LD.

Pneumatic tube validation: Reducing the need for donor samples by integrating a vial-embedded data logger

“…Previous studies have shown a clear positive correlation between the AUC and changes in concentration of potassium, LDH and AST. 5,15,16 In our study, the mean AUC ranged from 53 (hand) to 581 (line E). Within this AUC spectrum, the concentration of potassium was unaffected.…”

“…which are all characteristics that will influence the vibrations the blood samples are subject to under PTS transport. 5,11,16 How much different line characteristics contribute to the cumulative vibrations (AUC) in the PTS is not well understood. Besides line F, where the AUC increased 97% post extension, the remaining five lines did only increase between 4.6 and 18.9% after the extension of 300 m (thus being doubled in length) which really emphasizes how unpredictable the vibrations in a PTS can be and why they must be directly measured.…”

“…In a recent study, Farnsworth et al 15 concluded that the AUC within a single route can vary 4-39%, with the between-day variability being greater than the within-day variability. Because few studies exist 6,15,16 and all use devices of varying sensor details (smartphones, mini-data loggers) to investigate their PTS with few AUC measurements, we found it essential to validate and test the stability of the system over more than just a few days. Accordingly, we designed a fiveday validation protocol.…”

“…1,9,12,13 As a result, the use of mini data loggers that mimic blood sample movement in the PTS has gained popularity since they provide repeatable measurements while reducing the time and effort required for PTS validation. 5,6,[14][15][16] Our hospital began the construction of a new laboratory in 2017, as part of a larger construction project. The new laboratory is located in the corner of our hospital, making the distance from the laboratory to the primary clinical departments 400-700 m long, and requiring the extension in the length of six previously installed PTS lines by 300 m. In addition to the new laboratory with the six extended PTS lines needing to be validated, the hospital will undergo a great expansion in the next few years, resulting in the installation of more than 40 new PTS lines.…”

Pneumatic tube transport of blood samples affects global hemostasis and platelet function assays

“…It has been hypothesized that shear stress exerted by PTS may activate platelets, 15 but studies of the PTS influence on hemostasis testing yield contradictory results and the impact remains therefore unclear. Studies found a decrease in the platelet aggregation response measured by whole blood impedance aggregometry using Multiplate Analyzer 13,15,16 and PFA‐100 ® , 17 whereas others show no relevant effect using Multiplate Analyzer, 18,19 PFA‐100 ® 20 and Chronolog 700 Aggregometer 21 . Contrastingly, most studies of the PTS influence on global hemostasis assays observe an effect on ROTEM ® parameters 22,23 and TEG parameters, 20,24,25 although one study found no impact on ROTEM ® 11 …”