Table 3: Univariate associations between level of daytime sleep on POD1 and patient and surgery characteristics.

 

Daytime inactivity/sleep ≤ 20%

(N  = 11)

Daytime inactivity/sleep 20% to 40%

(N  =  43)

Daytime inactivity/sleep > 40%

(N  =  102)

p-value

Patient Characteristics

Age, % 75+ years

64%

58%

72%

0.30*

Gender, % male

64%

56%

52%

0.73

Race, % White

55%

86%

74%

0.07*

Surgery Characteristics

Surgery type, %

 

 

 

 

General

27%

35%

57%

 

Major joint

45%

21%

10%

0.01*

Spine

27%

44%

33%

 

Surgery End Time, % 19:00 and later

18%

2%

14%

0.06*

Surgery Duration, % 6 hours or more

27%

18%

38%

0.07*

Postoperative Events

Postoperative pain, % ≤ 5

27%

35%

29%

0.77*

ICU, % admitted

0%

0%

6%

0.27*

Sleep Characteristics

Preoperative WASO

 

 

 

0.25*

≤ 15%

45%

51%

57%

 

15 to 25%

27%

40%

25%

 

> 25%

27%

9%

19%

 

Preoperative daytime sleep

 

 

 

0.41*

≤ 20%

36%

28%

18%

 

20 to 40%

55%

56%

58%

 

> 40%

9%

16%

24%

 

*Results from Fisher’s exact test

WASO: Wake After Sleep Onset; ICU: Intensive Care Unit; POD1: Postoperative Day 1

Daytime inactivity groupings are based on the frequency distribution of daytime inactivity for our cohort.