Am. J. Respir. Crit. Care Med., Vol 149, No. 4, 04 1994, 852-859.
Development of a patient-dedicated, on-demand, blood gas monitor
CK Mahutte, M Holody, TP Maxwell, PA Chen and SA Sasse
Department of Medicine, Veterans Affairs Medical Center, Long Beach, CA 90822.
A new monitor (CDI 2000) that brings blood gas measurements to the
patient's bedside has been developed. To measure blood gases, blood is
drawn into the patient's arterial pressure-monitoring line past in-line
fluorescent-based sensors. After measurement, the blood is returned to the
patient, avoiding blood loss and delays in sample turnaround and reducing
the risk of infection to both patient and operator. We assessed this
system's performance in vitro with tonometered bovine blood. Bias (mean
difference between monitor and tonometered gas or measured pH values) +/-
the standard deviation (SD) were 0.01 +/- 0.02 at pH = 7.39; 0.0 +/- 0.7 mm
Hg at Pco2 = 39 mm Hg; and 2.4 +/- 3.2 mm Hg at a Po2 = 100 mm Hg (n = 54).
Changes in hematocrit, blood temperature, or serum sodium concentration did
not have clinically significant effects on system performance. Studies in
normal volunteers, in whom large changes in blood gases were induced,
showed a bias (mean difference between monitor and IL 1306 values) +/- SD
of 0.00 +/- 0.02 for pH, -0.4 +/- 2.0 mm Hg for Pco2, and -3.6 +/- 7.7 mm
Hg for Po2 (n = 69). We conclude from the present study that the
performance of this system is comparable to that of conventional blood gas
analyzers.
