Table 2 Correlations (mixed linear regression) of Sco₂, Sso₂ and Svo₂ with haemodynamic and oxygen transport variables for the entire group and individually in 7 pigs and 11 patients.

Dependent variable	Independent variable	Intercept	Group slope	p Value	Range of individual slopes	p Value for interindividual slope difference
Pig data
Sco2	Svo2	28.1	0.30	<0.0001	0.14–0.67	0.0005
	Sao2	57.6	−0.11	0.82
	Pao2	48.0	−0.01	0.60
	Haemoglobin	52.4	−0.36	0.28
	MAP	18.6	0.64	<0.0001	−0.71–1.16	<0.0001
	CO	39.7	2.30	<0.0001	1.56–6.42	0.0006
	Do2	39.0	0.017	<0.0001	0.02–0.07	0.006
	V̇o2	39.9	0.01	0.48
	ERo2	59.7	−32.5	<0.0001	−65.4–16.4	0.002
Patient data
Sco2	Svo2	28.5	0.43	<0.0001	0.17–0.97	<0.0001
	Sao2	4.6	0.61	<0.0001	0.14–2.13	0.0001
	Pao2	12.1	0.99	<0.0001	0.36–1.93	<0.0001
	Haemoglobin	47.5	0.24	0.54
	MAP	26.0	0.52	<0.0001	0.14–1.11	0.21
	Qp	43.6	3.72	0.001	0.86–6.72	0.03
	Qs	42.1	3.22	<0.0001	0.27–13.64	0.002
	Do2	42.4	0.03	<0.0001	0.01–0.10	0.001
	V̇o2	56.8	−0.07	0.046	−0.33–0.39	<0.0001
	ERo2	61.1	−33.2	<0.0001	−91.7–−5.3	<0.0001
Sso2	Svo2	49.2	0.26	<0.0001	0.11–0.54	0.32
	Sao2	33.9	0.39	0.0001	Infinite likelihood
	Pao2	46.9	0.41	0.002	0.19–0.83	0.22
	Haemoglobin	58.2	0.30	0.48
	MAP	51.7	0.22	0.03	Infinite likelihood
	Qp	60.0	1.48	0.23
	Qs	59.3	1.73	0.03	0.46–10.3	0.28
	Do2	58.2	0.015	0.004	0.006–0.066	0.11
	V̇o2	63.3	−0.007	0.84
	ERo2	68.9	−20.3	0.0002	Infinite likelihood
Svo2	Qp	47.1	2.49	0.02	−9.3–10.8	0.04
	Qs	40.5	5.82	<0.0001	3.1–11.3	0.02
	Do2	36.4	0.05	<0.0001	0.032–0.097	0.001
	V̇o2	69.7	−0.20	<0.0001	−0.45–0.028	0.008
	ERo2	77.9	−83.2	<0.0001	−91.9–−69.4	0.18

Do₂, systemic oxygen delivery; ERo₂, oxygen extraction ratio; MAP, mean arterial pressure; Pao₂, arterial oxygen pressure; Qp, pulmonary blood flow; Qs, systemic blood flow; Sao₂, arterial oxygen saturation; Sco₂, cerebral oxygen saturation; Sso₂, splanchnic oxygen saturation; Svo₂, superior vena caval oxygen saturation; V̇o₂, systemic oxygen consumption.