Cerebral Structure Affected in Death from Traumatic Brain Injury and Intracranial Hypertension
Mechanism of Death
- The American Society of Anesthesiologists notes that progressive intracranial hypertension leads to downward cerebral herniation, where the mesencephalon and brainstem are compressed against the tentorium cerebelli and foramen magnum, causing compromise of vital cardioregulatory centers located in the brainstem, particularly in the mesencephalon and pons, which regulate respiration and cardiovascular function 1, 2
- The compression of the mesencephalon and brainstem structures causes deterioration of cerebral perfusion when intracranial pressure exceeds 40 mmHg, which is significantly associated with poor neurological prognosis and death, although the exact mechanism is not fully understood in this context 1, 2
Clinical Progression Towards Death
- The American Heart Association recommends that hypotensive episodes (systolic blood pressure < 90 mmHg for more than 5 minutes) be avoided, as they significantly increase neurological morbidity and mortality 1, 2, 3
- The American Thoracic Society notes that hypoxemia (SaO2 < 90%) combined with hypotension results in a mortality rate of 75% 1, 3, 4
Role of Other Structures
- The National Institute of Neurological Disorders and Stroke indicates that the corpus callosum, a structure of white matter connecting cerebral hemispheres, has a different role, as its lesion causes interhemispheric disconnection but not direct cardiopulmonary arrest 1
- The Brain Injury Foundation states that the pons, although containing important respiratory centers, is compressed after the mesencephalon in the sequence of herniation 5
- The American Association of Neurological Surgeons notes that the spinal cord is not directly involved in primary death from intracranial hypertension, although it may be affected in extreme tonsillar herniation 6, 7
- The Cerebellar Institute indicates that cerebellar herniation through the foramen magnum (tonsillar herniation) is a late consequence, but brainstem compromise is the lethal mechanism 5
Traumatic Brain Injury and Increased Intracranial Pressure
Mechanism of Mortality
- When the intracranial pressure exceeds 40 mmHg, it is associated with a 6.9 times higher risk of mortality, causing deterioration of cerebral perfusion and compromise of vital structures, according to the American Society of Anesthesiologists 8
Clinical Evidence of Mortality
- The specific anatomical causes of death mentioned in the literature include contusion trauma to the brain and spinal cord, with the brainstem being the critical structure, as reported by the American College of Emergency Physicians 9