Table 1 Baseline characteristics of 140 dogs treated surgically for pyometra, stratified by allocated treatment (pre/intraoperative antibiotics: yes/no)

Age (in years; median, range)

9

1; 14

9

3; 15

0.433

Weight (in kg; median, range)

14

2; 65

10.5

2; 40

0.280

Type of pyometra (n, %)

0.111

 Open

70

78.0

33

66.0

 Closed

19

21.0

17

34.0

 Not recorded

1

1.0

0

0.0

ASA classification (n, %)

0.001*

 < 3

43

47.8

10

20.0

 ≥ 3

18

20.0

20

40

 Not recorded

29

32.2

20

40.0

Preoperative temperature (in ℃; mean, sd)

38.7

0.70

39.0

0.81

0.019*

General demeanour (n, %)

< 0.001*

 Good or mildly depressed

83

92.2

7

14.0

 Moderately depressed

5

5.6

35

70.0

 Severely depressed

2

2.2

8

16.0

Concurrent diseases present (n, %)

41

45.6

28

56.0

0.290

 Mammary tumour

11

12.2

6

12.0

1

 Cardiac disease

11

12.2

6

12.0

1

 Dermatological disease

8

8.9

2

4.0

0.495

 Osteoarthritis

5

5.6

5

10.0

0.329

 Other

16

17.8

14

28.0

0.198

Peritonitis present (n, %)

1

1.1

16

32.0

< 0.001*

Duration of surgery (in minutes; median, range)

60

10; 185

67.5

20; 235

0.055