Table 5.

Univariate and multivariate analyses of factors associated with postoperative delirium (PD) in the entire cohort.

variable	Univariate			Multivariate
	OR	95% CI	P-value	OR	95% CI	P-value
Individualized vs. standard anesthesia	0.592	0.251–1.398	0.232
Age	1.113	1.016–1.220	0.021
BMI	0.992	0.869–1.132	0.902
Gender (Male vs. Female)	0.711	0.308–1.643	0.425
ASA classification ≥3	4.328	1.655–11.318	0.003
Organic brain disease	6.767	2.761–16.585	0.000	6.308	2.458–16.187	0.000
Minimally invasive approach	0.522	0.208–1.310	0.166
Anesthesia technique
GA	1	Referent
GA+EA	0.570	0.231–1.406	0.222
GA+PVB	0.916	0.277–3..031	0.886
Duration of anesthesia	1.001	0.995–1.008	0.685
Duration of surgery	1.002	0.995–1.009	0.623
Intraoperative fluid infusion	1.000	0.999–1.001	0.983
BIS baseline	0.887	0.797–0.989	0.030
BIS minimal during surgery	1.026	0.978–1.076	0.296
BIS maximal during surgery	0.989	0.938–1.043	0.688
Hypertension during surgery	0.592	0.251–1.398	0.232
Hypotension during surgery	1.991	0.850–4.664	0.113
Inadequate emergence	4.370	1.866–10.234	0.001	4.063	1.645–10.033	0.002
Perioperative blood transfusion	2.913	1.045–8.120	0.041

PD – postoperative delirium; BMI – body weight index; ASA – American Society of Anesthesiologist; GA – general anesthesia; PVB – paravertebral block; EA – epidural anesthesia; BIS – bispectral index; OR – odd ratios; CI – confidence intervals.