Table 1.

Demographics of patients undergoing elective cranial neurosurgery for malignant brain tumors between 2002 and 2011.

Variable	No surgical complication	Surgical complication	P-value
No. cases	15,963	567
Age	53.9 ± 16.3	54.7 ± 17.3	0.126
Sex (male, %)	57.5	59.8	0.286
Elixhauser comorbidity score (median, IQR)	1 (0–8)	2 (0–6)	<0.001
Urban hospital (%)	97.6	96.7	0.234
Teaching hospital (%)	84.2	82.6	0.394
Complications (%)	5.4	19.2	<0.001
Pneumonia (%)	0.6	3.5	<0.001
Myocardial infarction (%)	0.1	1.9*	0.059
Acute kidney injury (%)	0.5	1.9*	<0.001
Respiratory complication (%)	1.1	9.0	<0.001
Pancreatitis (%)	0.1*	1.9*	0.075
UTI (%)	2.4	9.9	<0.001
DVT (%)	1.0	5.1	<0.001
PE (%)	0.2	1.9*	0.034
Surgical site complication (%)	0.3	3.9	<0.001
Length of stay (mean)	4.4 ± 4.7	11.8 ± 11.8	<0.001
Mortality (%)	0.7	9.0	<0.001
Total charges ($)	53,638 ± 41,801	111,518 ± 105,304	<0.001

IRQ: interquartile range, UTI: urinary tract infection, DVT: deep vein thrombosis, PE: pulmonary embolism.

Boldface denotes statistically significant results.

^*NIS does not allow the publication of values that are less than or equal to 10 observations, so the number 11 was used to calculate percentages.