Table 1.
Case mix, outcome and activity for admissions with primary or secondary reason for admission to ICU of asthma
| All (n = 2152) | Mechanically ventilateda (n = 1223) | Not mechanically ventilateda (n = 929) | |
| Case mix | |||
| Age (mean ± SD; years) | 43.6 ± 19.2 | 47.4 ± 18.6 | 38.6 ± 18.8 |
| Sex (% male) | 33.2 | 34.8 | 31.0 |
| Steroid treatment during previous 6 months (%) | 14.1 | 13.9 | 14.3 |
| CPR within 24 hours before ICU admission (%) | 8.0 | 12.4 | 2.0 |
| Neurological insult during the first 24 hours (%) | 10.3 | 17.0 | 1.5 |
| Highest heart rate (mean ± SD; beats/min) | 133 ± 21.8 | 134 ± 21.9 | 132 ± 21.7 |
| Highest nonventilated respiratory rate (mean ± SD; breaths/min) | 30 ± 10.3 | 26 ± 9.8 | 32 ± 9.9 |
| Lowest PaO2 (median [IQR]; kPa) | 10.9 (9.3–13.4) | 10.7 (9.2–12.9) | 11.3 (9.4–14.3) |
| pH from ABG with lowest PaO2 (median [IQR]) | 7.37 (7.29–7.42) | 7.34 (7.25–7.40) | 7.40 (7.35–7.44) |
| PaCO2 from ABG with lowest pH (median [IQR]; kPa) | 6.9 (5.2–9.5) | 8.2 (6.3–10.7) | 5.3 (4.5–6.6) |
| Acute Physiology Score (mean ± SD)b | 11.0 ± 5.5 | 12.5 ± 5.7 | 8.6 ± 4.2 |
| APACHE II score (mean ± SD)b | 13.8 ± 6.6 | 15.7 ± 6.7 | 11.0 ± 5.2 |
| Outcomec | |||
| Mortality in CMP unit (n [%]) | 133 (6.3) | 123 (10.3) | 10 (1.1) |
| Mortality in any hospital (n [%]) | 199 (9.8) | 177 (15.4) | 22 (2.5) |
| Activity | |||
| Stay in CMP unit (median [IQR]; days) | 1.5 (0.7–3.5) | 2.6 (1.3–6.7) | 0.8 (0.5–1.5) |
| Stay in any hospital (median [IQR]; days) | 8 (5–15) | 10 (6–19) | 6 (4–10) |
| Transfers in from another hospital (%) | 11.8 | 17.4 | 4.4 |
| Readmissions within the same hospital stay (%) | 2.3 | 2.1 | 2.6 |
aDuring first 24 hours after admission to the Case Mix Programme (CMP) unit. b248 (11.5%) admissions aged <16 years or staying <8 hours in the intensive care unit (ICU) excluded from the calculation of Acute Physiology Score and Acute Physiology and Chronic Health Evaluation (APACHE) II score. cExcluding 50 (2.3%) readmissions to ICU within the same hospital stay. ABG, arterial blood gas; IQR, interquartile range; PaO2, arterial oxygen tension; SD, standard deviation.