Laboratories on the move: Blood gas analysis

We evaluated the performance of a portable instrument for measuring pH, P-CO2, and P-O2 during land and air transport of critical care patients. We determined accuracy and precision by analyzing control materials with known values and by running duplicate analyses of patient specimens. The control data showed that the instrument performed as well in a moving ambulance and in an airborne jet-powered aircraft as it did while in a stationary position on the ground. Duplicate results of patient specimens showed good correlation. The maximum differences between mean control values were 0.002 for pH, 0.2 mm Hg for P-CO2, and 3.9 mm Hg for P-O2. For P-CO2 and P-O2, the precision was slightly lower in the moving vehicles than on the ground, but appeared adequate for medical decisions. Our results indicate that this analyzer produces acceptable blood gas results in moving vehicles.