Figure 4:

(A) Measurements of PCO₂ with the i-STAT system vs. set PCO₂. Mean values are indicated by the larger, open symbols. (B) The relative error of i-STAT PCO₂ measurements, δPCO₂ (expressed as a % ), [calculated as: (i-STAT PCO₂ − control PCO₂)/control PCO₂ × 100] vs. control PCO₂. Continuous lines represent the fitted models and dashed lines represent the lines of identity. (C) Effects of temperature (in °C ), Hct (L, low; H, high) and PCO₂ (in mmHg) on δPCO₂ (expressed as a %). Significant effects within treatments are indicated as NS for non-significant and ‘*’ at the P < 0.05 level. Data are means ± SEM, and statistical analysis was performed on the absolute δPCO₂ values.