Table 1.
Baseline patient and monitoring characteristics
| Low TIL(N = 445) | High TIL (N = 313) | p-value | |
|---|---|---|---|
| Age (median, IQR) | 51 [30.0–65.0] | 41 [27.0–65.0] | < 0.001 |
| Gender, male (N,%) | 326/445 (73.3) | 235/313 (75.1) | 0.632 |
| Injury severity (GCS at baseline) | |||
| Mild > = 13 (N, %) | 77/414 (18.6) | 29/296 (9.8) | 0.002 |
| Moderate > = 9—< 13(N, %) | 78/414 (18.8) | 51/296 (17.2) | 0.653 |
| Severe < 9 (N, %) | 259/414 (62.6) | 216/296 (73.0) | 0.005 |
| ISS without head injury (median, IQR) | 10 [0.0–25.0] | 13 [0.0–25.0] | 0.286 |
| CT (N,%) | |||
| tSAH | 306/367 (− 83.4) | 228/253 (− 90.1) | 0.023 |
| EDH | 73/366 (− 19.9) | 58/254 (− 22.8) | 0.443 |
| Marshall (N, %) | |||
| 1 | 11/367 (− 3) | 5/253 (− 2) | < 0.001 |
| 2 | 168/367 (− 45.8) | 94/253 (− 37.2) | |
| 3 | 30/367 (− 8.2) | 57/253 (− 22.5) | |
| 4 | 8/367 (− 2.2) | 5/253 (− 2) | |
| 5 | 2/367 (− 0.5) | 2/253 (− 0.8) | |
| 6 | 148/367 (− 40.3) | 90/253 (− 35.6) | |
| Preinjury ASA (N, %) | 0.001 | ||
| 1) Normal healthy | 230/428 (− 53.7) | 194/296 (− 65.5) | |
| 2) Mild systemic disease | 144/428 (− 33.6) | 88/296 (− 29.7) | |
| 3) Severe systemic disease | 51/428 (− 11.9) | 13/296 (− 4.4) | |
| 4) Severe systemic disease, a constant threat to life | 3/428 (− 0.7) | 1/296 (− 0.3) | |
| Cause of injury (N, %) | 0.295 | ||
| Road traffic incident | 212/430 (− 49.3) | 148/301 (− 49.2) | |
| Incidental fall | 166/430 (− 38.6) | 106/301 (− 35.2) | |
| Violence/assault | 15/430 (− 3.5) | 18/301 (− 6) | |
| Suicide attempt | 10/430 (− 2.3) | 4/301 (− 1.3) | |
| Other | 27/430 (− 6.3) | 25/301 (− 8.3) | |
| Prehospital1 (N, %) | |||
| Hypoxia | 89/445 (− 20) | 39/313 (− 12.5) | 0.009 |
| Hypotension | 80/445 (− 18) | 47/313 (− 15) | 0.329 |
| Lab1 (median, IQR) | |||
| Hemoglobin (g/dL) | 13.1 [11.6–14.4] | 13.2 [11.9–14.3] | 0.694 |
| Glucose (mmol/L) | 7.9 [6.7–9.9] | 7.8 [ 6.7–9.8] | 0.933 |
| Type ICP monitor (N, %) | 0.511 | ||
| Ventricular | 53/445 (− 11.9) | 38/312 (− 12.2) | |
| Ventricular + inbuilt sensor | 7/445 (− 1.6) | 10/312 (− 3.2) | |
| Parenchymal | 366/445 (− 82.2) | 250/312 (− 80.1) | |
| Other | 19/445 (− 4.3) | 14/312 (− 4.5) | |
| Multimodal cerebral monitoring (N, %) | |||
| Jugular oximetry | 9/445 (− 2) | 20/312(− 6.4) | 0.004 |
| Brain tissue PbtO2 | 84/445 (− 18.9) | 65/312 (− 20.8) | 0.555 |
| Transcranial Doppler | 34/444 (− 7.7) | 78/312 (− 25) | < 0.001 |
| Microdialysis | 48/445 (− 10.8) | 30/311 (− 9.6) | 0.7 |
| Continuous EEG | 21/445 (− 4.7) | 38/311 (− 12.2) | < 0.001 |
| Electrocorticography | 4/444 (− 0.9) | 1/311 (− 0.3) | 0.61 |
| Systemic monitoring (N, %) | |||
| Invasive blood pressure monitoring | 432/445 (− 97.1) | 306/312 (− 98.1) | 0.53 |
| Cardiac output | 74/444 (− 16.7) | 80/312 (− 25.6) | 0.003 |
| Pulse oximetry | 436/445 (− 98) | 303/312 (− 97.1) | 0.6 |
| End tidal CO2 | 335/444 (− 75.5) | 213/312 (− 68.3) | 0.036 |
| Central venous pressure | 261/444 (− 58.8) | 190/312 (− 60.9) | 0.612 |
| Mechanical ventilation | |||
| Present | 416/441 (− 94.3) | 287/312 (− 92) | 0.261 |
This table describes the baseline characteristics of patients with a high versus a low therapy intensity level (TIL). High TIL was defined as any high intensity treatment (decompressive craniectomy excluding day 1, barbiturates, intensive hypothermia, intensive hyperventilation) during the ICU stay. Significant group differences were determined by using the chi-square or Fisher’s exact test (non-normal distributions) for categorical variables and an ANOVAS or Kruskal Wallis test (non-normal distributions) for continuous variables
1IMPACT, first available
ASA score: American Society of Anesthesiologists (ASA) Physical Status score, CO2: carbon dioxide, CT: Computed tomography, CRBSI: catheter-related blood-stream infection EEG: electroencephalogram, GCS: Glasgow Coma Scale, ICP: intracranial pressure, ISS: injury severity score, IQR: interquartile range, PbtO2: brain tissue partial pressure of oxygen, TIL: therapy intensity level