Traumatic brain injury affects millions of people worldwide each year. The first peak in incidence occurs in young adults from car accidents, and the second in older adults from falls. In this group of patients, it is important to early select people at risk of premature death and sudden deterioration of health, and to early implement individual, “tailor-made” clinical therapy after trauma. Another intracranial pathology that affects young adults and middle-aged people is subarachnoid hemorrhage from a ruptured aneurysm. In patients with a ruptured aneurysm, spasms of the cerebral vessels are a major problem, which can lead to poor treatment results and paresis, hence early vasospasm detection and selecting patients at risk is so important. Both these groups of patients are linked by the occurrence of changes in the autonomic nervous system and cerebral autoregulation. However, the relationship between autonomic nervous system impairment and cerebral autoregulation in terms of treatment outcomes and mortality prediction remains under investigation. My research project aimed to analyze the dynamics of changes in the activity of the autonomic nervous system and to understand the influence of the potential relationship between cerebral autoregulation and the activity of the autonomic nervous system in the context of brain perfusion, treatment outcomes, and mortality in patients with intracranial pathologies. This analysis is possible using three elements: firstly, biosignals that are routinely monitored in intensive care units (such as blood pressure or intracranial pressure), secondly, advanced algorithms and mathematical methods that allow determining parameters and metrics describing the recorded signals, and that we can program in a computer-readable language and, thirdly, expert knowledge that allows us to interpret the results and propose a clinical application.

My research results indicate that in patients with cerebral vasospasm, there is no significant relationship between cerebral autoregulation and the activity of arterial baroreceptors, both before and during vasospasm. In other words, if a patient does not develop such a correlation, he is at risk of vasoconstriction. In addition, my research results indicate that in patients with ruptured aneurysms, the impairment of the autonomic nervous system is related to the degree of disturbance in perfusion, i.e. brain oxygenation – the greater the decrease in oxygen content in the brain tissue, the worse the activity of the autonomic nervous system. In patients with brain injuries, there is a desynchronization between the activity of arterial baroreceptors and intracranial pressure. In my research, I found that the weaker the relationship between one signal and another, the worse the patient’s prognosis. Thus, monitoring the dynamics and synchronization of the autonomic nervous system and intracranial pressure can help clinicians predict mortality. What is more, I showed that the trend that we observe in the activity of arterial baroreceptors after a brain injury may carry valuable information about the patient’s condition. If after 2-3 days of suppressing the baroreflex, which is caused by the brain injury, there is an increase in baroreceptors activity – the patient has a good chance of a favorable result of the treatment.

I presented the results of my work on the autonomic nervous system and cerebral autoregulation in patients with brain trauma and subarachnoid hemorrhage at the Brain Physics Lab, Department of Clinical Neurosciences, University of Cambridge (UK) seminar during my visit, which was financed by the MINIATURE program. These results were enthusiastically received by scientists from this world-renowned research center. Therefore, there is a chance that thanks to the use of advanced methods of signal and data processing, we will be able to better and more effectively treat intracranial pathologies shortly.