Table 2 Respiratory depression occurrence when patients were breathing room air, intermittently receiving SO, or always receiving SO

 ≥ 1 OIRD Episode

 Percent of patients with ≥ 1 OIRD episode (n/N)

54.1% (40/74)

60.2% (53/88)

62.5% (25/40)

0.615

 Number of OIRD episodes per patient (Median, IQR)

4.5 (2.0- 9.5)

6.0 (2.0- 18.0)

8.0 (2.0- 20.0)

0.420

 Number of OIRD episodes per patient per monitored hour (Median, IQR)

0.3 (0.1- 0.4)

0.3 (0.1- 0.6)

0.9 (0.2- 1.3)

0.017

Respiratory Depression Episode Subtype

 ≥ 1 Apnea Episode

 Percent of patients with ≥ 1 apnea episode

48.6% (36/74)

56.8% (50/88)

60.0% (24/40)

0.427

 Number of apnea episodes per patient (Median, IQR)

4.0 (2.0- 9.0)

5.0 (2.0- 17.0)

8.0 (2.5- 18.5)

0.238

 Number of apnea episodes per patient per monitored hour (Median, IQR)

0.2 (0.1- 0.4)

0.3 (0.1- 0.6)

0.7 (0.3- 1.3)

0.005

 ≥ 1 Respiratory Rate Episode

 Percent of patients with ≥ 1 respiratory rate episodes

13.5% (10/74)

19.3% (17/88)

12.5% (5/40)

0.488

 Number of respiratory rate episodes per patient (Median, IQR)

1.0 (1.0- 1.0)

1.0 (1.0- 2.0)

3.0 (2.0- 3.0)

0.096

 Number of RR episodes per patient per monitored hour (Median, IQR)

0.1 (0.0- 0.1)

0.1 (0.0- 0.1)

0.1 (0.1- 0.1)

0.108

 ≥ 1 SpO₂ Episode

 Percent of patients with ≥ 1 SpO₂ episodes

9.5% (7/74)

9.1% (8/88)

12.5% (5/40)

0.825

 Number of SpO₂ episodes per patient (Median, IQR)

3.0 (1.0- 9.0)

1.0 (1.0- 2.5)

1.0 (1.0- 3.0)

0.157

 Number of SpO₂ episodes per patient per monitored hour (Median, IQR)

0.1 (0.1- 0.5)

0.1 (0.0- 0.1)

0.0 (0.0- 0.1)

0.241