Table 3.

Univariate Cox regression analysis results

Variables	β	SE	Wald	HR	95%CI	P
Age	0.006	0.011	0.308	1.006	0.985–1.027	0.579
BMI	0.002	0.027	0.952	1.002	0.949–1.057	0.952
Hypertension
No	Reference
Level 1	0.242	0.322	0.566	1.274	0.678–2.393	0.452
Level 2	0.619	0.297	3.342	1.857	1.037–3.325	0.068
Level 3	0.553	0.303	3.343	1.739	0.961–3.147	0.068
Nature of occupation
Manual worker	Reference
Non-manual worker	−0.706	0.241	8.582	0.494	0.308–0.792	0.003
Medical payment method	0.159	0.202	0.618	1.172	0.789–1.740	0.432
First blood sugar	0.009	0.021	0.168	1.009	0.967–1.052	0.682
Mechanical ventilation duration	0.001	0.001	0.269	1.001	0.998–1.003	0.604
APACHE-II score
< 15	Reference
≤15–20	0.664	0.233	8.126	1.943	1.231–3.069	0.004
> 20	1.622	0.303	28.740	5.064	2.779–9.165	< 0.001
ICU stay	−0.044	0.024	3.335	0.956	0.912–1.003	0.068
Hypoxemia	0.894	0.213	17.545	2.445	1.609–3.715	< 0.001
Analgesics and sedatives
0–2	Reference
3–4	0.896	0.266	11.381	2.450	1.456–4.123	0.001
> 4	1.760	0.387	20.650	5.811	2.720–12.413	< 0.001
Aortic cross-clamping duration	0.001	0.002	0.315	1.001	0.997–1.006	0.575

SE Standard error, HR Hazard ratio, CI Confidence intervals

BMI Body mass index, APACHE-II Acute physiology and chronic health evaluation II