Table 5.
Bivariate analysis of transport variables and presence of adverse eventsa
| Variable | Adverse event (n = 40) | No adverse event (n = 140) | P value |
| Patient characteristics | |||
| Age, years | 57 ± 16 | 55 ± 16 | 0.44 |
| Female gender | 43 | 43 | 0.97 |
| Glasgow Coma Scale score | 5 (3–8) | 5 (3–9) | 0.57 |
| Outside hospital length of stay, days | 1 (1–2) | 1 (1–3) | 0.52 |
| Pre-flight presence of vasopressors, number (percentage) | 18 (45) | 30 (21) | <0.01 |
| Pre-flight fraction of inspired oxygen, percentage | 0.77 ± 27 | 0.72 ± 30 | 0.39 |
| PEEP prior to flight | 5 ± 5 | 6 ± 4 | 0.25 |
| Patient in emergency room when transferred | 39 | 37 | 0.84 |
| Use of manual ventilation during flight, number (percentage) | 5 (12.5) | 17 (12) | 1.0 |
| Hospital characteristics | |||
| Bed size | |||
| <200 | 9 (26%) | 38 (30%) | 0.6 |
| 200–400 | 13 (37%) | 53 (42%) | |
| >400 | 13 (37%) | 36 (28%) | |
| Academic institution | 15 (43%) | 58 (46%) | 0.77 |
| Transfer characteristics | |||
| Landing zone on site at transferring hospital | 19 (49) | 61 (46) | 0.75 |
| Nighttime transfer | 15 (38%) | 58 (41%) | 0.66 |
| Winter transfer | 6 (15%) | 33 (24%) | 0.25 |
| Distance, km | 57 (35–95) | 47 (31–82) | 0.02 |
| Flight time, minutes | 15 (10–24) | 12 (8–20) | 0.32 |
Values are presented as number (percentage), mean ± standard deviation, or median (interquartile range), as appropriate. aFor 180 patients with complete physiologic data during flight. PEEP, positive end-expiratory pressure.