Background: The pneumatic tube system (PTS) has been implicated in
inducing haemolysis. It is not known whether certain sample types are more
susceptible to haemolysis than others. We assessed the level of haemolysis in
commonly used sample types in the clinical biochemistry department when transported
through the PTS.
Method: Blood was collected in pairs for different sample types and sent
to the laboratory via the pneumatic tube or delivered by a porter. Haemolysis indices
were measured spectrophotometrically and compared for each pair of sample type.
Results: Our results suggest that plain serum samples are more
susceptible to haemolysis than the other sample types when sent through our PTS
(P <0.0001). Compared with serum with gel samples, plain serum
samples are more prone to haemolysis (P <0.001). This suggests
that gel may confer some protection against haemolysis.
Conclusion: Different hospitals will have varying system configurations
and use different sample types. We recommend that each hospital investigate their own
system to assess whether haemolysis is a recurring problem in any of the sample types
transported.
