Table 4 Multivariate hurdle model of factors predicting duration of postoperative oxygen therapy use in children undergoing non-cardiac surgery

Probable difficult airway

2.19 (1.39, 3.48)

0.0008

History of delayed development

2.31 (1.49, 3.57)

0.0002

ASA physical status (Ref: 1)

0.03^a

 2

0.75 (0.43, 1.32)

 3

1.07 (0.61, 1.88)

Site/type of procedure (Ref: Eye)

<0.0001

 Urologic

1.98 (0.99, 3.96)

 Airway

3.01 (1.55, 5.83)

 Ear-nose-face

2.27 (1.06, 4.82)

 Thoracic

4.86 (2.34, 10.1)

 Intra-abdomen

4.15 (2.13, 8.11)

 Orthopedic

2.14 (1.08, 4.25)

 Intra-cranial

1.26 (0.52, 3.02)

 Gastrointestinal scope

2.73 (1.23, 6.04)

 Cardiac catheterization

1.18 (0.53, 2.60)

Narcotic used (Ref: None)

0.049^b

 Morphine

0.69 (0.40, 1.20)

 Fentanyl

1.10 (0.72, 1.68)