A large Venous-Arterial PCO₂ Is Associated with Poor Outcomes in Surgical Patients

Table 1

Patient characteristics and comparison between patients with [P(v-a) CO₂] < 5.0 and [P(v-a)CO₂] ≥ 5.0.

Variables	All patients; (𝑛=66)	[P(v-a)CO2] < 5.0 mmHg; (𝑛=22)	[P(v-a)CO2] ≥ 5.0 mmHg; (𝑛=44)	𝑃
Age	65.6±12.2	64.6±13.5	66.0±11.7	0.67
Males (%)	56.1	50.0	59.1	0.48
APACHE II	16.9±5.6	15.8±5.1	17.4±5.8	0.29
MODS	3 (1.0–4.0)	3.0 (1.0–4.0)	3.5 (1.0–4.5)	0.46
ASA (%)				0.65
I	6.6	9.5	5.0
II	68.9	71.4	67.5
III	24.6	19.0	27.5
Elective surgery (%)	95.5	95.5	95.5	1.00
Emergency surgery (%)	4.5	4.5	4.5	1.00
Gastrointestinal surgery (%)	78.8	81.8	73.3	0.38
[P (v-a) Co2] (mmHg)	5.4±2.0	3.3±1.2	6.5±1.4	0.00
Lactate (mmol/L)	1.5±0.8	1.4±0.6	1.6±0.9	0.35
Base excess (mmol/L)	−0.7 (−3.0–0.6)	−1.6 (−3.4–0.7)	−0.5 (−2.4–0.6)	0.35
ScvO2 (%)	74.1±7.6	77.0±6.2	72.7±7.9	0.03
Ventricular dysfunction (%)	77.3	54.5	88.6	0.002
Ejection fraction (%)	63.7±9.5	63.5±9.9	63.9±92	0.93
Hemoglobin (g/dL)	11.4±1.7	11.3±1.7	11.5±1.7	0.70
Glucose (mg/dL)	120.0±54.2	120.7±61.7	120.3±50.8	0.98

ScvO₂-central venous oxygen saturation; ASA: American Society of Anesthesiologists; values between brackets represent the median and percentile 25–75%.