The physiological determinants of near-infrared spectroscopy-derived regional cerebral oxygenation in critically ill adults

Intensive Care Medicine Experimental

Table 2 Regression models predicting the near-infrared spectroscopy regional cerebral oxygenation signal in critically ill adult patients

Predictor	Simultaneous regression model			AICc selected regression model
Predictor	b	β	r	b	β	r
Age	− 0.08 [− 0.17, 0.01]	− 0.22 [− 0.48, 0.03]	− 0.32*	− 0.10 [− 0.19, − 0.01]*	− 0.27 [− 0.51, − 0.04]	− 0.32*
HR	0.06 [− 0.02, 0.14]	0.19 [− 0.06, 0.44]	0.22	0.08 [0.01, 0.15]*	0.25 [0.02, 0.49]	0.22
SpO₂	− 0.37 [− 1.19, 0.44]	− 0.15 [− 0.48, 0.18]	− 0.42**
MAP	0.02 [− 0.16, 0.20]	0.03 [− 0.23, 0.28]	0.22
pH	− 16.44 [− 38.52, 5.65]	− 0.19 [− 0.45, 0.07]	− 0.34*
PaO₂	0.05 [− 0.05, 0.15]	0.13 [− 0.14, 0.41]	− 0.07
PaCO₂	0.16 [0.00, 0.33]*	0.30 [0.00, 0.59]	0.57**	0.21 [0.07, 0.34]**	0.37 [0.13, 0.62]	0.57**
Hb	0.09 [0.02, 0.15]**	0.40 [0.11, 0.69]	0.43**	0.09 [0.04, 0.14]**	0.41 [0.16, 0.66]	0.43**
Fit	R² = 0.579** [0.22, 0.65]; adjusted R² = 0.480			R² = 0.535 [0.25, 0.65]**; adjusted R² = 0.487

b represents unstandardized regression weights. β indicates the standardized regression weights. r represents the zero-order correlation. The [] indicate the lower and upper limits of the 95% confidence interval, respectively. The gray-shaded region represents the predictors that were not retained following model selection
AICc corrected Akaike information criterion, HR heart rate, SpO₂ arterial oxygen saturation, MAP mean arterial pressure, PaO₂ arterial partial pressure of oxygen, PaCO₂ arterial partial pressure of carbon dioxide, Hb hemoglobin
*p < 0.05
**p < 0.01