Table 2 Frequency of extreme hypoxemic and hyperoxemic episodes

 Total

103(15–175)

216 (118–352)

< 0.001

 < 5 s

42 (22–74)

67 (34–116)

< 0.05

 5- < 30 s

45 (22–92)

61 (36–105)

ns

 30- < 60 s

9 (3–17)

14 (9–23)

< 0.01

 60 - < 120 s

1 (0–3)

6 (3–11)

< 0.001

 120+ s

0 (0–1)

2 (1–4)

< 0.001

 Total

24 (8–63)

75 (34–147)

< 0.001

 < 5 s

11 (3–24)

23 (11–47)

ns

 5- < 30 s

11 (4–29)

26 (12–63)

< 0.05

 30- < 60 s

3 (0–8)

8 (3–17)

< 0.001

 60 - < 120 s

0 (0–3)

3 (1–8)

< 0.001

 120+ s

0 (0–1)

1 (0–4)

< 0.001