[Transcranial Doppler in anesthesia and intensive care]

Area of Science:

• Neurology
• Medical Imaging
• Vascular Ultrasound

Background:

• Transcranial Doppler (TCD) sonography is a non-invasive ultrasound technique.
• It utilizes a low-frequency probe to record signals from basal cerebral arteries.
• Established normal reference values exist for Doppler parameters in these arteries.

Purpose of the Study:

• To review the principles, methodology, and clinical applications of Transcranial Doppler sonography.
• To highlight the utility of TCD in various medical scenarios, including anesthesia and intensive care.
• To emphasize the importance of careful interpretation of TCD results in conjunction with other diagnostic data.

Main Methods:

• Utilizes three primary approaches: transtemporal, transorbital, and sub-occipital.
• Examines specific arteries including anterior, middle, and posterior cerebral arteries, ophthalmic artery, carotid canal, basilar artery, and intracranial vertebral arteries.
• Measures Doppler parameters influenced by vessel diameter, PaCO2, cerebral blood flow, and cerebrovascular resistances.

Main Results:

• TCD has numerous clinical applications in anesthesia (e.g., cardiopulmonary bypass, carotid endarterectomy) and critical care.
• It is valuable for assessing vasospasm after subarachnoid hemorrhage.
• Monitoring cerebral blood flow velocities aids in managing meningitis, head injuries, and ischemic-anoxic diseases.

Conclusions:

• Transcranial Doppler sonography is a versatile tool with expanding clinical applications.
• TCD provides crucial information for managing patients with cerebrovascular conditions.
• Results from TCD should always be interpreted cautiously alongside other clinical investigations.