Gender and Low Albumin and Oxygen Levels are Risk Factors for Perioperative Pneumonia in Geriatric Hip Fracture Patients

Figures & data

Table 1 Demographic Characteristics and Major Comorbidities

Item	Non-POP (n=260)	POP(n=33)	χ^2 or t value	P-value
Age (years)	85.1±3.4	84.5±3.2	0.692	0.490
Gender(male/female)	76/184	20/13	13.086	0.000*
Smoking(%)	24(9.2%)	8(24.2%)	6.783	0.009*
COPD(%)	8(3.1%)	2(6.1%)	0.791	0.374
Hypertension	130(50%)	18(54.6%)	0.242	0.623
Coronary heart disease	48(18.5%)	10(30.3%)	2.586	0.108
Arrhythmia	14(5.4%)	2(6.1%)	0.026	0.872
Type 2 diabetes	44(16.9%)	6(18.2%)	0.033	0.856
Prior stroke	45(17.3%)	6(18.2%)	0.016	0.901
Chronic renal failure	10(3.9%)	3(9.1%)	1.900	0.168
Dementia	4(1.5%)	1(3.0%)	0.389	0.533
Parkinson’s disease	10(3.9%)	1(3.0%)	0.054	0.816
Tumors	34(13.1%)	4(12.1%)	0.024	0.878

Note: *P<0.05.

Abbreviations: Non-POP, non- perioperative pneumonia; POP, perioperative pneumonia; COPD, chronic obstructive pulmonary disease.

Table 2 Fractures and Treatment Details

Items	Non-POP (n=260)	POP(n=33)	χ^2	P-value
Fracture type			0.042	0.837
Intertrochanteric	131	16
Femoral neck	129	17
Surgical procedures			1.394	0.498
Intramedullary fixation	36	2
Hip replacement	184	18
Other procedures	4	1
ASA scores			0.390	0.532
I/II	209	25
III/IV	51	8
Anesthesia method			0.029	0.866
General	24	2
Regional	200	19

Notes: Other procedures included extramedullary fixation, external fixation, and simple fixation.

Abbreviations: Non-POP, non- perioperative pneumonia; POP, perioperative pneumonia; ASA, American society of anesthesiologists.

Table 3 Baseline Laboratory Examinations

Items	Non-POP (n=260)	POP(n=33)	t value	P value
Arterial Blood Gas Analysis
Oxygen pressure	73.00±13.45	67.57±17.78	1.492	0.138
Carbon dioxide pressure	34.40±6.24	33.71±5.19	0.439	0.661
Oxygen saturation	94.47±2.56	92.39±4.61	1.824	0.085
Blood Routine Test
Leukocyte	9.28±3.56	10.70±2.19	−1.605	0.111
Hemoglobin	124.02±15.33	123.71±16.36	0.080	0.937
Platelet	204.42±68.06	221.00±88.53	−0.908	0.365
Neutrophilic granulocyte percentage	78.15±9.162	81.96±6.14	−2.243	0.033*
Serum Biochemical Analyses
Alanine transaminase	14.97±25.87	30.41±68.69	−0.918	0.372
Aspartate transaminase	21.48±36.71	31.06±41.55	−0.994	0.322
Serum albumin	39.90±5.20	34.99±8.55	2.246	0.039*
Alkaline phosphatase	76.05±46.76	55.94±18.11	1.788	0.076
Gamma-glutamyl transpeptidase	31.13±29.49	38.75±28.16	−0.976	0.331
Creatinine	72.38±27.70	80.65±19.71	−1.189	0.237
Urea nitrogen	7.38±3.10	8.88±3.08	−1.867	0.064
Electrolytes
Potassium	4.19±0.47	4.07±0.43	1.002	0.318
Sodium	139.83±10.01	138.75±5.66	0.435	0.664
Chlorine	105.07±3.59	104.41±4.64	0.685	0.494

Note: *P<0.05.

Abbreviations: Non-POP, non- perioperative pneumonia; POP, perioperative pneumonia.

Table 4 Univariate Logistic Regression Analyses for Risk Factors of POP

Variables	χ^2 value	p value
Gender, male	13.086	0.000*
Smoking history	6.783	0.009*
Oxygen level	6.707	0.035*
Hypoalbuminemia	14.350	0.000*
Neutrophilic granulocyte level, elevated	2.299	0.129

Note: *P<0.05.

Abbreviation: POP, perioperative pneumonia.

Table 5 Multivariate Logistic Regression Analyses for Risk Factors of POP

Variables	OR	95% CI		p value
		Lower	Upper
Gender, male	3.402	1.012	11.439	0.048*
Smoking	2.580	0.440	15.113	0.293
Hypoalbuminemia	10.159	2.698	38.251	0.001*
Oxygen level	2.916	1.346	6.316	0.007*

Note: *P<0.05.

Abbreviations: POP, perioperative pneumonia; OR, odds ratio; CI, confidence interval.