Table 2.

Patient’s clinical characteristics

Variable	Delirium (n = 59)	Non-delirium (n = 247)
Age	81.9 ± 5.4	76.4 ± 8.1	t = − 0.647	p = 0.000
Gender(M/F)	23/36	81/166	χ2 = 0.813	p = 0.367
Hypertension (n)	27	147	χ2 = 3.672	p = 0.550
Coronary heart disease (n)	35	187	χ2 = 6.421	p = 0.011
Diabetes (n)	36	192	χ2 = 7.006	p = 0.008
Cerebral infarction (n)	44	214	χ2 = 5.240	p = 0.020
Hospitalization	24.2 ± 15.1	16.0 ± 7.2	t = − 4.102	p = 0.000
Preoperative hospitalization	5.5 ± 3.4	3.7 ± 1.7	t = − 3.677	p = 0.000
Albumin infusion	16.7 ± 33.1	1.8 ± 7.1	t = − 3.449	p = 0.000
Preoperative HCT	33.5 ± 4.9	35.2 ± 5.2	t = 2.327	p = 0.021
Postoperative HCT	28.2 ± 4.9	29.4 ± 4.8	t = 1.641	p = 0.102
BMI	22.2 ± 3.2	22.7 ± 3.2	t = 1.080	p = 0.281
Blood transfusion volume	1.4 + 2.1	0.5 ± 1.0	t = − 3.296	p = 0.002
Preoperative leucocyte count	9.6 ± 2.6	8 ± 2.1	t = − 4.072	p = 0.000
Preoperative Hb	11.3 ± 1.6	12.0 ± 5.5	t = 0.840	p = 0.402
Preoperative albumin	36.5 ± 3.7	37.8 ± 4.0	t = 2.132	p = 0.034
Preoperative TP	64.6 ± 4.8	64.7 ± 5.8	t = 0.046	p = 0.963
NYHA	2.2 ± 0.7	1.8 ± 0.6	t = − 3.606	p = 0.001
ASA	2.9 ± 0.5	2.4 ± 0.5	t = − 7.713	p = 0.000
Anesthesia	25/34	126/121	χ2 = 1.422	p = 0.233
Surgery	30/29	114/133	χ2 = 0.421	p = 0.516
Operation time	88.5 ± 40.3	79.0 ± 24.3	t = − 1.733	p = 0.088
The anesthesia time	157.7 ± 50.9	150.3 ± 33.4	t = − 1.066	p = 0.290
Intraoperative blood loss	127.1 ± 95.2	105.1 ± 33.4	t = − 1.666	p = 0.046
Postoperative Na+	139.0 ± 4.7	139.6 ± 4.0	t = 0.922	p = 0.357
Postoperative K+	4.3 ± 0.5	4.3 ± 0.4	t = 0.309	p = 0.758
Postoperative leucocyte count	9.6 ± 2.6	8.6 ± 2.4	t = − 2.717	p = 0.007
Postoperative Hb	9.4 ± 1.9	9.7 ± 1.6	t = 1.237	p = 0.217
DVT (N)	15	52	t = 0.523	p = 0.466

ASA American Society of Anesthesiologists, NYHA New York Heart Association, BMI body mass index, DVT deep venous thrombosis, HCT hematocrit, Hb hemoglobin, TP total protein, F female, M male, N numbers