The reliability of the i-STAT clinical portable analyser

Authors: B.J. Dascombe, P.R.J. Reaburn, A.C. Sirotic, A.J. Coutts

Summary

The purpose of this investigation was to assess the reliability of the i-STAT clinical portable analyser and CG4+ cartridge measures of blood pH, partial pressures of O2 (pO2 ) and CO2 (pCO2 ), bicarbonate ([HCO3 − ]), base excess (BE), total carbon dioxide (TCO2), oxygen saturation (sO2) and blood lactate ([BLa−]) at various exercise intensities. A comparison between [BLa−] measured by the i- STAT and the Accusport lactate analysers during an intermittent treadmill run was also undertaken. The technical error of measurement (TEM%) at rest, at moderate (200 W) and maximal exercise (V ̇O2 max) was acceptable (<15%) for all parameters. The intra-class correlation coefficients for each analyte ranged from weak- to-strong across resting (ICC = 0.19—0.96) and moderate (ICC = 0.30—0.96) exercise intensities. The ICC for all analytes were observed to be strong following maxi- mal intensity exercise (ICC=0.77—0.95).

The comparison of the [BLa−] measures between the i-STAT and Accusport showed that the difference between measures was acceptable at both low (<4mmolL−1) (−0.39±0.27mmolL−1), moderate to high concentrations (>4 mmol L−1 ) (0.58 ± 1.22 mmol L−1 ), and across all [BLa− ] data (0.36 ± 1.13 mmol L−1 ). In conclusion, the i-STAT clinical analyser and CG4 + cartridge provides reliable measures of a number of blood parameters across exercise intensities. The [BLa−] measures from the i-STAT analyser are consistent with that of the Accusport lactate analyser.

Crown Copyright © 2006 Published by Elsevier Ltd on behalf of Sports Medicine Australia. All rights reserved.