Is a Second Transcranial Doppler Study Needed to Confirm Neurocirculatory Arrest?

Area of Science:

• Neurology
• Critical Care Medicine
• Diagnostic Imaging

Background:

• Transcranial Doppler (TCD) is recommended for brain death determination when clinical exams are contraindicated.
• Current guidelines suggest two TCDs 30 minutes apart to diagnose neurocirculatory arrest.
• This study questions the necessity of a second TCD if the initial one indicates neurocirculatory arrest.

Purpose of the Study:

• To evaluate if a second TCD is necessary when the first TCD shows neurocirculatory arrest.
• To assess the consistency of TCD findings in diagnosing neurocirculatory arrest.
• To potentially refine brain death diagnostic protocols.

Main Methods:

• Retrospective analysis of 48 intensive care unit patients from January 2021 to February 2025.
• Inclusion criteria: first TCD showed neurocirculatory arrest, followed by a confirmatory TCD at least 30 minutes later.
• Comparison of findings between the first and second TCD studies.

Main Results:

• The second TCD confirmed neurocirculatory arrest in 100% of patients (48/48).
• 91.7% (44/48) had identical flow patterns on both TCDs.
• 8.3% (4/48) showed different but still consistent neurocirculatory arrest patterns on the second TCD.

Conclusions:

• A single TCD demonstrating neurocirculatory arrest may be sufficient for diagnosis.
• The requirement for two sequential TCDs might be unnecessary in certain cases.
• Further large-scale studies are warranted to validate these findings.