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Clinically Relevant Blood Pressure Elevation During Apnea Testing for Brain Death Determination: Association With
Geon Hwee Jeon1, Dong-Keun Hyun1
1Department of Neurosurgery, Inha University Hospital, Incheon, Korea.
Korean Journal of Neurotrauma
|August 7, 2026
Summary
Apnea testing for brain death determination significantly elevates blood pressure and heart rate. These hemodynamic changes occur without a corresponding rise in catecholamines, suggesting other mechanisms are involved.
Area of Science:
- Cardiology
- Neurology
- Critical Care Medicine
Background:
- Apnea testing is crucial for diagnosing brain death.
- Hemodynamic responses during apnea testing are not fully understood.
- The role of catecholamines in these responses requires further investigation.
Purpose of the Study:
- To characterize hemodynamic changes during apnea testing.
- To evaluate the clinical relevance of these hemodynamic changes.
- To explore associations between apnea testing and circulating catecholamines.
Main Methods:
- Retrospective analysis of 27 patients undergoing apnea testing.
- Measurement of heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) at baseline and post-test.
- Measurement of plasma catecholamines in a subset of patients.
Main Results:
- Apnea testing significantly increased SBP, HR, and DBP (p<0.001).
- Post-test SBP frequently exceeded 140 mmHg and 160 mmHg.
- Epinephrine levels increased modestly, while norepinephrine and dopamine remained unchanged.
Conclusions:
- Apnea testing induces significant hemodynamic changes.
- These responses occur independently of significant catecholamine elevations.
- Additional mechanisms likely mediate the observed hemodynamic effects during apnea testing.
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