The Science Journal of the American Association for Respiratory Care
Background: Arterial blood gases and electrolytes are the most frequently ordered laboratory tests in the critical care environment. They are extremely important in the management of neonates with congenital heart disease, especially in the perioperative period when ventilator management plays a central role in the manipulation of pulmonary vascular resistance. The VIA-LVM (VIA Medical, San Diego, CA) is an in-line, on-demand blood gas/electrolyte monitor. We evaluated the use of the VIA-LVM in neonates following surgery for congenital heart defects. Method: Upon return from the operating room, the VIA-LVM was attached to the arterial line. During sampling, blood was drawn for correlation with laboratory analysis using the Corning 855 blood gas and electrolyte analyzer (Chiron Diagnostics, Norwood, MA). Results were compared for bias and precision using Bland and Altman analysis. A total of 140 samples were collected from 7 patients.
Results: (see Figure 1) pH: r2=0.94, bias=-0.02, precision=0.03; pCO2: r2=0.86, bias=2.1 mm Hg, precision=3.6 mm Hg; pO2: r2=0.95, bias=7.2 mm Hg, precision=11.7 mm Hg,; Sodium: r2=0.85, bias=2.9 mmol/L, precision=2.5 mmol/L; Potassium: r2=0.88, bias=0.4 mmol/l, precision=0.5 mmol/L; and Hematocrit: r2=0.80, bias=-3.8, precision=3.9.
Conclusions: Based on the results of this study, we found the VIA-LVM correlated well with conventional laboratory analysis methods. The VIA-LVM provided rapid results within 70 seconds with minimal blood loss.