Table 2.
Characteristics of the study population
| Characteristic | Group A (control individuals; n = 26) | Group B (moderate brain injury; n = 18) | Group C (severe brain injury; n = 32) |
| Age (years; mean ± SD) | 49 ± 19 | 43 ± 14 | 49 ± 18 |
| Sex (male/female; n) | 21/5 | 12/6 | 25/7 |
| BMI (kg/m2; mean ± SD) | 20 ± 4.9 | 20 ± 4.5 | 19.2 ± 6.0 |
| GCS (1 to 14; median [range]) | 14 | 11.1 (8 to 13) | 4.9 (3 to 7)* |
| Diagnosis upon admission (n [%]) | Trauma: 11 (42%) | Head injury: 18 (100%) | Head injury: 32 (100%) |
| Sepsis: 8 (31%) | |||
| ARDS: 5 (19%) | |||
| Burn: 2 (8%) | |||
| ONSD (mm; mean ± SD [range]) | 3.6 ± 0.6 (2.2 to 4.9) | 4.2 ± 1.2 (3.0 to 6.2) | 6.1 ± 0.7 (5.2 to 7.8)* |
| eICP (mmHg; mean ± SD [range]) | 10.3 ± 3.1 (3.5 to 14.7) | 12.0 ± 3.6 (6.3 to 18.4) | 26.2 ± 8.7 (14.4 to 51.1)† |
| ICP (mmHg; mean ± SD [range]) | - | - | 26.0 ± 7.3 (16.0 to 47.0) |
| CPP (mmHg; mean ± SD [range]) | - | - | 61.8 ± 12.0 (29.0 to 85.0) |
| Brain CT injury scale upon admission (I to VI; n [%]) | Normal | I: 18 (100%) | II: 4 (12.5%) |
| III: 16 (50.0%) | |||
| IV: 4 (12.5%) | |||
| V: 4 (12.5%) | |||
| VI: 4 (12.5%) |
*Statistically significant difference in GCS and ONSD values between group C and groups A and B (P < 0.0001; Student's t-test). †Statistically significant difference in eICP values between group C and groups A and B (P < 0.0001; Student's t-test). ARDS, adult respiratory distress syndrome; BMI, body mass index; CPP, cerebral perfusion pressure; CT, computed tomography; eICP, non-invasive intracranial pressure; GCS, Glasgow Coma Scale; ICP, invasive intracranial pressure; ONSD, optic nerve sheath diameter; SD, standard deviation.