Effect of acceleration forces during transport through a pneumatic tube system on ROTEM® analysis.

Background: ROTEM® is considered a helpful point-of-care device to monitor blood coagulation in emergency situations. Centrally performed analysis is desirable but rapid transport of blood samples is an important prerequisite. The effect of acceleration forces on sample transport through a pneumatic tube system on ROTEM® should be tested at each institution to exclude a pre-analytical influence. The aims of the present work were: (i) to investigate the effect of pneumatic tube transport on ROTEM® parameters; (ii) to compare blood sample transport via pneumatic tube vs. manual transportation; and (iii) to determine the effect of acceleration forces on ROTEM® parameters.

Methods: This is a single centre study with 20 healthy volunteers. Five whole blood samples were transferred to the central haematology laboratory by either normal transport or pneumatic delivery with different speed and acceleration forces. EXTEM, INTEM, FIBTEM and APTEM were analysed in parallel with two ROTEM® devices and compared. Acceleration forces were measured during transport with two different instruments.

Results: Increment of transport time, speed and distance resulted in an augmentation of acceleration forces and peaks. All results of the ROTEM® analysis after manual transport or pneumatic delivery were within normal range. However, increase in acceleration forces resulted in minimally but statistically significant changes in multiple ROTEM® parameters. The higher the acceleration forces, the more ROTEM® parameters are influenced.

Conclusions: Acceleration forces during transport through a pneumatic tube system have an influence on ROTEM® parameters. Prior to transfer blood samples via pneumatic tube system these influences should be tested to exclude clinically relevant blood coagulation activation in vitro.