Evaluation of posttraumatic vasospasm, hyperaemia, and autoregulation by transcranial colour-coded duplex sonography

Area of Science:

• Neuroscience
• Medical Imaging
• Critical Care Medicine

Background:

• Severe head injury (GCS ≤ 8) poses significant risks for cerebral complications.
• Cerebral vasospasm and impaired autoregulation are critical concerns in traumatic brain injury (TBI).

Purpose of the Study:

• To evaluate cerebral hemodynamics using serial transcranial colour-coded duplex sonography (TCCS) in severe head injury patients.
• To assess the incidence and impact of vasospasm and impaired autoregulation on outcomes.

Main Methods:

• Serial TCCS was performed on 24 adult patients with severe head injury.
• Flow velocities in the middle cerebral artery (MCA) and extracranial internal carotid artery (EICA) were measured.
• Transient hyperaemic response test was used for autoregulation assessment.

Main Results:

• Vasospasm (MCA velocity > 100 cm/s, Lindegaard ratio > 3) was detected in 37% of patients, significantly associated with poor outcomes (p < 0.05).
• Vasospasm onset was around day 2, peaking around day 4, and persisting for two weeks.
• Impaired autoregulation was observed in 29% of patients and significantly associated with hyperaemia (p < 0.05).
• No correlation was found between subarachnoid hemorrhage (SAH) extent on CT and vasospasm.

Conclusions:

• TCCS provides non-invasive evaluation of cerebral hemodynamics in head-injured patients.
• Early detection and monitoring of vasospasm are crucial for managing severe head injury.
• Cerebral vasospasm is a significant predictor of poor outcomes in severe head injury.