ORIGINAL ARTICLE

Changes in blood gas samples produced by a pneumatic tube system

P O Collinson, C M John, D C Gaze, L F Ferrigan, D G Cramp

Department of Chemical Pathology, Mayday Hospital, London Road, Croydon CR7 7YE, UK

Correspondence to:
Correspondence to:
Dr PO Collinson, Department of Clinical Biochemistry, 2nd Floor, Jenner Wing, St George's Hospital, Blackshaw Road, London SW17 0QT, UK;
poctrop{at}poctrop.demon.co.uk

Aims: To investigate the effect of a pneumatic tube system (PTS) on the results of samples sent for blood gas analysis to a central laboratory.

Methods: Blood gas samples were analysed immediately or sent via the PTS to the laboratory for analysis. In addition, samples sent via the PTS in a pressure sealed container were compared with those sent non-pressure sealed to the laboratory.

Results: Samples sent via the PTS had significant alterations in their pO₂ values, which were not seen when samples were carried by hand to the laboratory. There was no effect on pCO₂ and pH values. The use of a pressure sealed container abolished the alteration in pO₂ values seen.

Conclusions: Samples for blood gas analysis should be transported via a PTS using a pressure sealed container to avoid artefacts in the pO₂.

Keywords: pneumatic tube system; blood gas analysis; pressurised container; oxygen pressure

Abbreviations: CV, coefficient of variation; ICU, intensive care unit, IQR, interquartile range; NS, not significant; POCT, point of care testing; PTS, pneumatic tube system; TAT, turnaround time

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?