Demographic characteristics
| Characteristic | % of entire cohort* | % of propensity score–matched cohort* | ||||
|---|---|---|---|---|---|---|
| Nondelayed n = 12 340 | Delayed n = 2820 | Absolute standardized difference† | Nondelayed n = 2820 | Delayed n = 2820 | Absolute standardized difference† | |
| Priority level | ||||||
| A | 4.6 | 7.4 | 11.8 | 6.4 | 7.4 | 3.9 |
| B | 7.5 | 5.4 | 8.6 | 5.4 | 5.4 | 0 |
| C | 10.2 | 7.1 | 16.7 | 7.3 | 7.1 | 0.8 |
| D | 29.9 | 12.2 | 44.5 | 12.0 | 12.2 | 0.6 |
| E | 47.9 | 67.9 | 41.4 | 68.9 | 67.9 | 2.2 |
| Age, yr, mean ± SD | 56.7 ± 20.7 | 60.8 ± 20.3 | 14.7 | 59.5 ± 20.8 | 60.8 ± 20.3 | 6.3 |
| Sex, female | 50.0 | 51.9 | 3.8 | 50.3 | 51.9 | 3.2 |
| Elixhauser Index, mean (IQR) | 2.0 (4.4) | 2.0 (4.4) | 0 | 1.9 (4.3) | 2.1 (4.4) | 4.6 |
| Hospital admission status, urgent | 95.2 | 95.6 | 1.9 | 95.7 | 95.6 | 0.5 |
| Hospital entry through ED | 84.8 | 84.7 | 0.3 | 84.6 | 84.7 | 0.3 |
| ASA physical status score | ||||||
| I and II | 32.0 | 25.8 | 13.7 | 28.3 | 25.8 | 5.6 |
| III and IV | 65.7 | 71.8 | 13.2 | 69.7 | 71.8 | 4.6 |
| V | 2.2 | 2.3 | 0.7 | 1.9 | 2.3 | 2.8 |
| Surgical service of record | ||||||
| Dental | 1.0 | 1.9 | 7.5 | 2.0 | 1.9 | 0.7 |
| General surgery | 32.3 | 21.1 | 25.5 | 21.1 | 21.1 | 0 |
| Gynecology | 5.0 | 2.6 | 12.6 | 2.4 | 2.6 | 1.3 |
| Neurosurgery | 7.2 | 8.2 | 3.8 | 8.6 | 8.2 | 1.4 |
| Ophthalmology | 1.5 | 1.2 | 2.6 | 1.3 | 1.2 | 0.9 |
| Orthopedic surgery | 27.3 | 42.2 | 31.7 | 41.9 | 42.2 | 0.6 |
| Otolaryngology | 2.0 | 1.9 | 0.7 | 1.8 | 1.9 | 0.7 |
| Plastic surgery | 1.6 | 0.8 | 7.4 | 0.8 | 0.8 | 0 |
| Thoracic surgery | 2.2 | 2.6 | 2.6 | 2.6 | 2.6 | 0 |
| Urology | 12.0 | 9.5 | 37.5 | 9.9 | 9.5 | 1.4 |
| Vascular surgery | 7.2 | 7.6 | 1.5 | 7.1 | 7.6 | 1.9 |
| Other | 0.8 | 0.1 | 3.7 | 0.1 | 0.1 | 0 |
| Direct to operating theatre from ED | 9.3 | 3.5 | 23.9 | 3.2 | 3.5 | 1.7 |
| In ICU when surgery booked | 3.2 | 3.5 | 1.7 | 3.2 | 3.5 | 1.7 |
| PIMR score, mean ± SD | 0.7 ± 1.5 | 0.9 ± 1.5 | 10.0 | 0.9 ± 1.6 | 0.9 ± 1.5 | 0 |
| CTAS | ||||||
| 1 | 3.6 | 2.7 | 5.2 | 4.0 | 2.7 | 7.2 |
| 2 | 40.8 | 37.4 | 7.0 | 37.5 | 37.4 | 0.2 |
| 3 | 52.8 | 57.8 | 10.1 | 56.4 | 57.8 | 2.8 |
| 4–5 | 2.9 | 2.2 | 4.4 | 2.9 | 2.2 | 4.4 |
| Transfusion within 24 h before surgery | 3.7 | 5.5 | 8.6 | 4.3 | 5.5 | 5.6 |
| Piperacillin–tazobactam or meropenem before arrival in operating room | 6.6 | 8.2 | 6.1 | 7.4 | 8.2 | 3.0 |
| Preoperative steroids | 4.0 | 5.6 | 7.5 | 5.2 | 5.6 | 1.8 |
| Preoperative insulin | 11.5 | 14.9 | 10.1 | 13 | 14.9 | 5.5 |
| LAPS, mean ± SD | 22.6 ± 24.1 | 22.0 ± 37.2 | 1.9 | 22.4 ± 21.7 | 22.0 ± 37.2 | 3.2 |
Note: ASA = American Society of Anesthesiology physical status score (higher categories predict higher risk of death), CTAS = Canadian Emergency Department Triage and Acuity Scale, ED = emergency department, ICU = intensive care unit, IQR = interquartile range, LAPS = Laboratory Acute Physiology Score (range 0–256; higher scores predict higher risk of death), PIMR = Procedural Index for Mortality Risk, SD = standard deviation.
↵* Except where indicated otherwise.
↵† Absolute standardized differences > 10 are considered represent an important difference.