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. 2025 Jul 7;143(4):835–850. doi: 10.1097/ALN.0000000000005646

Table 4.

Odds Ratio and 95% CI for the Risk Factors Associated with Any Adverse Events during Airway Management

Patient and Airway Management Characteristics Univariate Analysis (n = 17,007) Multivariable Analysis (n = 16,990)
Yes No OR (95% CI); P Value OR (95% CI); P Value
Total SD, IQR, or No. (%) Total SD, IQR, or No. (%)
Mean age, yr 4.7 4.4 6.3 4.8 0.92 (0.90–0.94); P < 0.001 0.92 (0.90–0.95); P < 0.001
Sex (male vs. female) 9,959 227 (2.3) 7,045 119 (1.7) 1.39 (1.10–1.76); P = 0.007 1.42 (1.12–1.80); P = 0.004
Median body weight, kg* 13.9 8.5, 21.2 17.5 10.7, 29.5
Place for airway management
 Mixed adult–pediatric hospital   
vs. pediatric hospital
2,584 58 (2.2) 14,423 288 (2.0)
 Catheter laboratory vs. operating room 262 4 (1.5) 16,624 337 (2.0) 1.00 (0.349–2.89); P = 0.99 1.01 (0.337–3.02); P = 0.99
 CT, MRI, radiation therapy rooms vs. operating room 49 4 (8.2) 16,624 337 (2.0) 5.3 (1.59–17.3); P = 0.006 5.7 (1.64–19.9); P = 0.006
Respiratory comorbidity
 Respiratory support 771 25 (3.2) 16,236 321 (2.0)
 Hypoxemia§ 507 12 (2.4) 16,500 334 (2.0)
 Apneic events 101 2 (2.0) 16,906 344 (2.0)
 Upper airway obstruction 381 13 (3.4) 16,626 333 (2.0)
 Laryngeal abnormalities 376 6 (1.6) 16,631 340 (2.0)
 Respiratory comorbidity 1,561 41 (2.6) 15,446 305 (2.0) 1.36 (0.96–1.94); P = 0.086 0.78 (0.51–1.20); P = 0.258
Airway sensitivity
 Active URI symptoms 422 20 (4.7) 16,585 326 (2.0)
 URI within 14 days without active symptoms 486 18 (3.7) 16,521 328 (2.0)
 Asthma 195 7 (3.6) 16,812 339 (2.0)
 Living with an active smoker 2,048 38 (1.9) 14,959 308 (2.1)
 Airway sensitivity 2,983 79 (2.7) 14,024 267 (1.9) 1.47 (1.11–1.96); P = 0.008 1.46 (1.09–1.94); P = 0.010
Environmental sensitivity
 Allergy for food or medication 807 17 (2.1) 16,200 329 (2.0)
 Allergic rhinitis 463 9 (1.9) 16,544 337 (2.0)
 Atopic dermatitis 407 6 (1.5) 16,600 340 (2.1)
 Environmental sensitivity 1,532 30 (2.0) 15,475 316 (2.0) 0.97 (0.65–1.45); P = 0.883 1.09 (0.73–1.65); P = 0.667
Cardiovascular comorbidity
 Shock status or cardiac arrest 51 2 (3.9) 16,956 344 (2.0)
 Congenital cardiac diseases 2,355 51 (2.2) 14,652 295 (2.0)
 Pulmonary hypertension 193 4 (2.1) 16,814 342 (2.0)
 Cardiovascular conditions 2,403 53 (2.2) 14,604 293 (2.0) 1.16 (0.84–1.59); P = 0.367 1.09 (0.74–1.62); P = 0.658
Physical condition
 ASA-PS score of III or higher 2,445 59 (2.4) 14,562 287 (2.0)
 Decreased muscle strength 200 3 (1.5) 16,807 343 (2.0)
 Preterm birth 2,448 68 (2.8) 14,559 278 (1.9)
 Low birth weight 2,222 60 (2.7) 14,785 286 (1.9)
 Physical condition 4,368 107 (2.5) 12,639 239 (1.9) 1.27 (0.99–1.62); P = 0.058 1.11 (0.84–1.48); P = 0.467
Chromosomal abnormality
 Trisomy 21 vs. none 327 5 (1.5) 16,320 328 (2.0)
 Trisomy 13 vs. none 16 1 (6.3) 16,320 328 (2.0)
 Trisomy 18 vs. none 20 2 (10.0) 16,320 328 (2.0)
 Other abnormalities vs. none 314 10 (3.2) 16,320 328 (2.0) 1.64 (0.82–3.28); P = 0.160
Gastrointestinal condition
 Noncompliance to nil per os 291 11 (3.8) 16,716 335 (2.0)
 Full-stomach pathophysiology# 379 16 (4.2) 16,626 330 (2.0)
 Nausea or vomiting 132 6 (4.6) 16,875 340 (2.0)
 Gastrointestinal condition 604 25 (4.1) 16,403 321 (2.0) 2.28 (1.44–3.63); P < 0.001 1.73 (0.97–3.07); P = 0.061
Type of surgery
 Cerebral 636 13 (2.0) 16,371 333 (2.0)
 Cardiac surgery 705 13 (1.8) 16,302 333 (2.0) 0.93 (0.51–1.67); P = 0.796 0.70 (0.36–1.36); P = 0.296
 Craniocervical 5,803 138 (2.4) 11,204 208 (1.9) 1.24 (0.98–1.56); P = 0.074 1.41 (1.09–1.83); P = 0.009
 Emergency surgery 1,076 36 (3.4) 15,931 310 (2.0) 1.77 (1.21–2.58); P = 0.003 1.47 (0.91–2.38); P = 0.116
Difficult airway evaluation
 Syndrome assuming difficult airway 359 25 (7.0) 16,648 321 (1.9) 3.98 (2.41–6.6); P < 0.001
 Difficult mask ventilation** 152 25 (16.5) 16,555 314 (1.9) 9.7 (5.6–17.1); P < 0.001
Preoperative difficult airway evaluation
 History of difficult airway 145 8 (5.5) 16,862 338 (2.0) 3.17 (1.41–7.1); P = 0.005
Anatomical features of difficult airway
 Limited cervical range of motion 70 1 (1.4) 16,937 345 (2.0) 0.64 (0.081–5.0); P = 0.669
 Limited mouth opening 78 6 (7.7) 16,929 340 (2.0) 4.3 (1.66–11.4); P = 0.003
 Short hyomental distance 27 2 (7.4) 16,980 344 (2.0) 3.60 (0.70–18.7); P = 0.127
 Upper airway obstruction 122 5 (4.1) 16,885 341 (2.0) 2.01 (0.75–5.4); P = 0.167
 Midface hypoplasia 74 1 (1.4) 16,933 345 (2.0) 0.58 (0.075–4.5); P = 0.604
 Macroglossia 87 3 (3.5) 16,920 343 (2.0) 1.75 (0.50–6.1); P = 0.380
 Micrognacia 348 21 (6.0) 16,659 325 (2.0) 3.39 (2.00–5.7); P < 0.001
 Macrocephaly 47 1 (2.1) 16,960 345 (2.0) 1.09 (0.14–8.8); P = 0.932
Preoperative difficult airway features
 One feature vs. none 530 20 (3.8) 16,336 317 (1.9) 2.00 (1.20–3.32); P = 0.007 1.74 (1.02–2.95); P = 0.042
 Two or more features vs. none 141 9 (6.4) 16,336 317 (1.9) 3.49 (1.59–7.7); P = 0.002 2.82 (1.21–6.6); P = 0.017
Airway management
 Attempt frequency (three times or more) 487 68 (14.0) 16,520 278 (1.7) 13.3 (8.3–21.5); P < 0.001
Reason for initiating a course
 Airway issue vs. planned 157 33 (21.0) 16,850 313 (1.9)
Least experienced provider in each course
 Frequent or occasional vs. specialist 2,199 45 (2.1) 3,434 92 (2.7) 0.82 (0.53–1.26); P = 0.363 0.88 (0.57–1.37); P = 0.575
 Trainee vs. specialist 10,158 180 (1.8) 3,434 92 (2.7) 0.77 (0.57–1.04); P = 0.086 0.80 (0.59–1.09); P = 0.159
Airway devices at first attempt
 Uncuffed ETT vs. cuffed ETT 965 21 (2.2) 11,502 262 (2.3)
 SGD placement vs. direct laryngoscopy†† 4,762 63 (1.3) 12,118 280 (2.3) 0.46 (0.340–0.62); P < 0.001 0.42 (0.288–0.62); P < 0.001
 Video laryngoscopy vs. direct laryngoscopy 2,015 67 (3.3) 9,978 219 (2.2) 1.82 (1.32–2.50); P < 0.001 0.70 (0.45–1.08); P = 0.109
Supportive maneuvers at first attempt
 Cricoid pressure 399 17 (4.3) 16,608 329 (2.0)
 External laryngeal manipulation 2,107 76 (3.6) 14,900 270 (1.8) 2.22 (1.66–2.96); P < 0.001 1.90 (1.41–2.56); P < 0.001
 Apneic oxygenation 191 9 (4.7) 16,816 337 (2.0)
Anesthesia management
 Induction method
  Intravenous vs. inhalational 5,921 118 (2.0) 11,067 223 (2.0) 0.92 (0.73–1.18); P = 0.526 1.05 (0.78–1.41); P = 0.749
  Rapid sequence 246 8 (3.3) 16,761 338 (2.0) 1.65 (0.76–3.59); P = 0.204 0.88 (0.36–2.15); P = 0.781
 Muscle relaxant use at first attempt 12,481 240 (1.9) 4,526 106 (2.3) 1.02 (0.78–1.34); P = 0.890 0.62 (0.43–0.89); P = 0.009
 Premedication 5,324 118 (2.2) 11,683 228 (2.0)

The data are described as numbers (%), means ± SDs, or medians (IQRs). The mean ± SD or median (IQR) values are shown in continuous variables (age and weight) by the presence (yes) and absence (no) of adverse events. The number (%) shows the occurrence of adverse events in nominal variables (sex [male vs. female], place for airway management (mixed adult–pediatric hospital vs. pediatric hospital; catheter laboratory vs. operating room; CT, MRI, or radiation therapy room vs. operating room), perioperative difficult airway features, reasons for initiating a course, least experienced provider in each course, airway devices at first attempt, and induction method). The multivariable regression analysis included the variables reported in the multivariable analysis columns. The maximal value of variance inflation factor of incorporated variables in the multilevel logistic regression model was 1.45.

*

Median body weight included one missing value.

Catheter laboratory vs. operating room included three missing values.

CT, MRI, radiation therapy rooms vs. operating room included three missing values.

§

Hypoxemia was defined as a peripheral arterial oxygen saturation of 94% or lower on room air.

Chromosomal abnormality included 10 missing values.

#

Full-stomach pathophysiology included two missing values.

**

Difficult mask ventilation included three missing values.

††

SGD placement vs. direct laryngoscopy included seven missing values.

ASA-PS, American Society of Anesthesiologists Physical Status; CT, computed tomography; ETT, endotracheal tube; IQR, interquartile range; MRI, magnetic resonance imaging; OR, odds ratio; SGD, supra glottic device; URI, upper respiratory infection.