Table 2 Descriptive statistics of patients' data

Age (y.o.)

27

73

52.93

11.564

Preoperative BUN (mmol/L)

3.90

12.90

9.2357

2.28065

Preoperative Cr (umol/L)

54.50

339.50

175.7619

82.80711

Indwelling time of drainage tube (month)

6

9

6.64

1.246

Hematuria disappearance time (day)

1

4

1.86

.872

BUN before tube removal (mmol/L)

3.80

9.10

6.2774

1.36499

Cr before tube removal (umol/L)

45.20

189.60

84.3786

27.25897

Follow-up time (month)

12

60

42.57

16.805

Narrow length (cm)

.20

2.10

1.0738

.53468