Effects of Pneumatic Tube Transport on Blood Gas and Supplemental Analytes

BACKGROUND: Pneumatic tube transport of blood gas samples is a common method of delivery within a facility. The effects of pneumatic tube transport on blood gas analysis has been studied. However, other analytes that are often assessed in blood gas analysis (eg, electrolytes, metabolites, and oximetry) are not typically included in these studies. We sought to investigate the impact of pneumatic tube transport on some of these other analytes.

METHODS: The study was conducted at the blood gas laboratory at the University of Utah Hospital. A split sample comparison was performed. Both samples were walked to a pneumatic tube station, where one sample was sent via tube to the blood gas laboratory, while the other sample was walked back to blood gas laboratory. We examined 2 samples from each of the 27 different pneumatic tube stations in this hospital. Results were graphed with upper and lower control limits set to conform to acceptable College of American Pathologists proficiency testing evaluation criteria. Data were compared using the Student t test.

RESULTS: Differences between walked and tubed specimens were neither clinically nor statistically significant.

CONCLUSIONS: Pneumatic tube transport of blood gas specimens is acceptable for blood gas and supplementary analytes, as evidenced by multiple points of evaluation, including statistical analysis, clinical judgment, and concordance with regulatory guidelines.