Nomogram to predict postoperative complications in elderly with total hip replacement

Table 1 Comparison of clinical data between no complications and complications

Patient characteristics	No complications (n = 355)	Complications (n = 59)	t/χ2/Z value	P value
Age (yr)1	74.06 ± 7.25	81.29 ± 8.19	6.96	0.000
Male gender (%)2	149 (41.9)	24(40.7)	0.03	0.852
Weight (kg)1	58.93 ± 10.23	57.2 ± 9.93	1.2	0.226
Comorbidities
Hypertension (%)2	114 (32.1)	30 (50.8)	7.83	0.006
Diabetes (%)2	50 (14.1)	16 (27.1)	6.41	0.017
Coronary heart disease (%)2	30 (5)	10 (16.9)	4.19	0.041
Stroke (%)2	16 (4.5)	12 (20.3)	20.11	0.000
Renal failure (%)2	13 (3.7)	7 (11.9)	7.404	0.017
Fractures (%)2	123 (34.6)	45 (76.3)	36.35	0.000
Laboratory data
WBC (109/L)1	7.6 ± 2.46	8.69 ± 2.93	2.7	0.003
RBC (1012/L)1	4.21 ± 0.59	3.89 ± 0.69	3.81	0.000
Hb (g/L)1	123.37 ± 20.99	111.89 ± 22.64	3.85	0.000
PLT (109/L)1	235.66 ± 71.56	247.91 ± 115.27	0.79	0.272
ALB (g/L)1	39.37 ± 4.51	35.75 ± 4.41	5.72	0.000
BUN (mmol/L)1	6.05 ± 4.02	7.71 ± 5.08	2.39	0.019
Intraoperative characteristics
EBL (mL)3	203.79 (50-1500)	229.8 (50-1000)	1.5	0.134
Lowest heart rate (bpm)1	59.39 ± 10.49	65.37 ± 13.88	3.16	0.001
Operation time (min)1	100.85 ± 40.26	89.41 ± 37.24	2.04	0.505
General anesthesia (%)2	159 (44.8)	24 (40.7)	0.35	0.556
ASA class ΙΙΙ or ΙV (%)2	159 (44.8)	518 (86.4)	39.35	0.000

¹t test;

²Chi-square test;

³Wilcoxon rank-sum test.

Preoperative patient characteristics for 414 total hip replacement procedures between March 1, 2017 and August 31, 2019. Results are presented as number (percentage) of patients, or as mean ± SD. The P values were obtained from chi-square tests, t-tests, or Wilcoxon rank-sum tests, as indicated. EBL: Estimated blood loss; ASA: American Society of Anesthesiologists.

Table 2 Multivariable logistic regression analysis results

Variables	OR	SE	Z	95%CI	P value
Age	1.05	0.02	2.04	1.00-1.09	0.041
Renal failure	3.96	2.44	2.23	1.18-13.27	0.026
Hypertension	1.31	0.47	0.74	0.65-2.64	0.457
Coronary heart disease	0.84	0.41	0.36	0.32-2.18	0.722
Diabetes	2.37	1.00	2.05	1.04-5.40	0.040
Stroke	2.41	1.15	1.84	0.94-6.16	0.066
Fractures	2.21	0.95	1.86	0.96-5.12	0.063
ASA class ΙΙΙ or ΙV	1.85	0.68	1.69	0.91-3.79	0.090
Lowest heart rate	1.02	0.01	1.10	0.99-1.05	0.272
RBC	1.05	0.34	0.16	0.56-1.99	0.869
WBC	1.03	0.64	0.44	0.91-1.16	0.657
Hb	1.00	0.01	0.10	0.98-1.02	0.922
ALB	0.90	0.04	2.73	0.83-0.97	0.006
BUN	1.00	0.04	0.13	0.94-1.08	0.893

RBC: Red blood cell; WBC: White blood cell; Hb: Hemoglobin; ALB: Albumin; BUN: Blood urea nitrogen; ASA: American Society of Anesthesiologists.