Target Blood Pressure Management in Head Trauma

Blood Pressure Targets

The American College of Anaesthesia recommends that for patients with traumatic brain injury, the target systolic blood pressure should be maintained above 110 mmHg with a mean arterial pressure (MAP) above 90 mmHg, and kept below 150 mmHg if within 6 hours of symptom onset when immediate surgery is not planned 1, 2, 3, 4
For patients with combined hemorrhagic shock and severe traumatic brain injury, the target MAP should be ≥80 mmHg 5
The cerebral perfusion pressure (CPP) target should be between 60-70 mmHg in the absence of multi-modal monitoring, and higher CPP values (>90 mmHg) may worsen neurological outcomes by aggravating vasogenic cerebral edema 6

The Anaesthesia society recommends using transduced direct arterial pressure monitoring with the transducer placed at the level of the tragus for accurate measurements, and if invasive monitoring is not immediately available, use NIBP measurements at 1-minute intervals during critical periods 1, 2
For hypotension management, vasoconstrictors such as ephedrine and metaraminol should be readily available to treat immediate hypotension, and 0.9% saline should be used as the preferred intravenous fluid for resuscitation 1, 2, 3
Hypotonic solutions such as Ringer's lactate should be avoided in patients with severe head trauma 5
For hypertension management, labetalol is recommended as a vasoactive agent, and aggressive BP reduction that might compromise cerebral perfusion should be avoided 1, 2

During intubation, maintaining target BP should be prioritized over concerns about cerebral stimulation, and high-dose fentanyl, alfentanil, or remifentanil TCI may be considered for induction 1, 2
Ketamine 1-2 mg/kg may be useful in hemodynamically unstable trauma patients, and lower doses should be used in unstable patients with multiple trauma 1, 2
For threatened intracranial hypertension or signs of brain herniation, mannitol 20% or hypertonic saline solution may be used, and prolonged hypocapnia should be avoided as a treatment for intracranial hypertension 6
PaCO₂ should be maintained between 4.5-5.0 kPa, with brief periods of 4.0-4.5 kPa allowed if impending uncal herniation 1, 2, 3
Hyperoxia should be avoided, especially in acute ischemic stroke, while maintaining adequate oxygenation (PaO₂ ≥13 kPa) 1, 2, 7

The American College of Critical Care recommends maintaining a mean arterial pressure (MAP) ≥80 mmHg in patients with traumatic head injury and hemorrhagic shock until major bleeding is controlled 8
The target MAP ≥80 mmHg should be maintained in patients with combined hemorrhagic shock and severe traumatic brain injury, as recommended by the Critical Care and Anaesthesia societies 8, 9, 10
A systolic blood pressure >90 mmHg should be maintained, as even brief episodes of hypotension below this threshold for ≥5 minutes are associated with significantly increased neurological morbidity and mortality 9, 10

Secondary brain injury prevention requires higher perfusion pressures, as hypotension is a key predictor of poor neurological outcome at 6 months following TBI 9, 10
Impaired cerebral autoregulation after TBI makes the brain dependent on systemic MAP, highlighting the importance of maintaining adequate blood pressure 9, 10

The Critical Care society recommends avoiding hypotonic solutions such as Ringer's lactate in patients with severe head trauma, as they may worsen cerebral edema 8
Permissive hypotension strategies used in isolated hemorrhagic shock should not be applied to patients with concurrent TBI, as recommended by the Critical Care and Anaesthesia societies 8, 9, 10