Table 2 Multivariate Cox regression of IRE based on period of anesthesia (n = 42,055)

Age (ref= > 6)

_

1^a 0.004

1^a < 0.001

1^a 0.048

1-6

1.5 (0.94, 2.3)^a

2.3 (1.6, 3.4)^b

2.0 (1.0, 4.1)^a

< 1

2.5 (1.5, 4.2)^b

3.0 (1.8, 4.8)^b

3.1 (1.2, 8.2)^b

Respiratory disease (ref = no)

_

1^a < 0.001

1^a 0.008

1^a 0.2

URI

1.4 (0.67, 2.9)^a

2.2 (1.3, 3.7)^b

2.1 (0.72, 6.3)^a

Pulmonary disease

3.5 (2.3, 5.5)^b

1.6 (0.9, 2.8)^a

2.1 (0.81, 5.7)^a

Site of operation (ref = superficial)

1^a < 0.001

_

_

_

Broncho/laryngoscopy

3.6 (2.0, 6.6)^b

Ear-nose-throat

1.6 (0.86, 2.8)^a

Eye

1.0 (0.55, 1.8)^a

Thoracic

1.1 (0.59, 2.2)^a

Abdomen

1.4 (0.83, 2.4)^a

Spine & extremity

1.3 (0.74, 2.3)^a

Remote*

1.3 (0.48, 2.8)^a

Position (ref = supine)

1^a 0.009

_

_

_

Lateral

2.0 (1.3, 3.1)^b

Lithotomy

0.50 (0.23, 1.1)^a

Prone

1.1 (0.51, 2.2)^{a b}

ASA classification (ref = 1)

1^a < 0.001

1^a 0.83

1^a 0.75

2

_

1.7 (0.96, 3.1)^a

1.0 (0.66,1.5)^a

1.3 (0.64, 2.7)^a

3

4.0 (2.1, 7.8)^b

1.1 (0.66, 2.0)^a

1.2 (0.38, 3.8)^a

Airway device (ref = ETT-C)

1^a < 0.001

Jet ventilation-C

2.4 (1.1, 5.1)^b

_

_

_

Facemask-A

2.4 (1.4, 4.0)^b

LMA-A

2.0 (1.2, 3.3)^b

Intubating agent (ref = NDMR)

1^a < 0.001

Succinylcholine

1.7 (1.2, 2.2)^b

_

_

_

Sevoflurane

1.6 (0.9, 2.7)^ab

Inhalation agent (ref = sevoflurane)

1^a 0.0013

Isoflurane

0.77 (0.58, 1.0)^a

Halothane

0.82 (0.26, 2.6)^a

_

_

_

Desflurane

3.9 (2.1, 7.2)^b