Research of Optimal Cerebral Perfusion Pressure Diagnosis

Study Overview
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Brief Summary
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The research will investigate the hypothesis that timely identification of the optimal value of the cerebral perfusion pressure (optCPP) or optimal arterial blood pressure (optABP) is possible after detecting informative episodes of arterial blood pressure (ABP) that reflects the physiological autoregulatory reactions of the cerebral blood flow, This biomedical study will be conducted to test this hypothesis and to develop an algorithm for identification of optimal brain perfusion pressure within limited time (several tens of minutes). The goal of this observational study is to test the method of timely optimal cerebral perfusion pressure value or optimal arterial pressure value in intensive care patients after brain surgery. The main question it aims to answer are: how long it takes to identify optimal cerebral perfusion value when arterial blood pressure is changing within safe physiological limits. Objectives of the study To perform a prospective observational study by collecting multimodal physiological brain monitoring data: intracranial pressure (ICP), arterial blood pressure (ABP), End-tidal carbon dioxide (ETCO2), cerebral blood flow velocity (CBFV), ECG. To perform a retrospective analysis of the accumulated clinical monitoring data, in order to create an algorithm for the identification of informative monitoring data fragments, according to which it would be possible to identify the optimal cerebral perfusion pressure (optCPP) value in a limited time interval (within a few or a dozen minutes). To perform a retrospective analysis of accumulated clinical monitoring data, determining correlations of cerebral blood flow autoregulation and optCPP-related parameters with the clinical outcome of patients and with the risk of cerebral vasospasm or cerebral ischemia.

Detailed Description
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Optimal cerebral perfusion pressure (optCPP) management requires at least 4 hours of patients' physiological data monitoring. Critical pathophysiological events in the injured brain happen in minutes, not in hours. The research will investigate the hypothesis that timely identification of the optimal value of the cerebral perfusion pressure (optCPP) or optimal arterial blood pressure (optABP) is possible after detecting informative episodes of arterial blood pressure (ABP) that reflects the physiological autoregulatory reactions of the cerebral blood flow, This biomedical study will be conducted to test this hypothesis and to develop an algorithm for identification of optimal brain perfusion pressure within limited time (several tens of minutes). The goal of this observational study is to test the method of timely optimal cerebral perfusion pressure value or optimal arterial pressure value in intensive care patients after brain surgery. The main question it aims to answer are: how long it takes to identify optimal cerebral perfusion value when arterial blood pressure is changing within safe physiological limits. Objectives of the study To perform a prospective observational study by collecting multimodal physiological brain monitoring data: intracranial pressure (ICP), arterial blood pressure (ABP), End-tidal carbon dioxide (ETCO2), cerebral blood flow velocity (CBFV), ECG. To perform a retrospective analysis of the accumulated clinical monitoring data, in order to create an algorithm for the identification of informative monitoring data fragments, according to which it would be possible to identify the optimal cerebral perfusion pressure (optCPP) value in a limited time interval (within a few or a dozen minutes). To perform a retrospective analysis of accumulated clinical monitoring data, determining correlations of cerebral blood flow autoregulation and optCPP-related parameters with the clinical outcome of patients and with the risk of cerebral vasospasm or cerebral ischemia. Timely identification of optCPP value and diagnosis of cerebrovascular autoregulation (CA) will be performed according to the measured reaction of cerebral hemodynamics during the detected ABP(t) changes.

Official Title
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Research and Development of Innovative Method and Technology for Cerebral Perfusion Pressure Diagnosis

Conditions
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Trauma, Brain, Hemorrhage Cerebral

Intervention / Treatment
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* Diagnostic Test: Multimodal physiological monitoring and cerebral autoregulation monitoring


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Traumatic brain injury patients Subarachnoid hemorrhage patients Exclusion Criteria: persons with mental disorders, but who can give consent to participate in biomedical research; minors; students, if their participation in biomedical research is related to studies; persons living in care institutions; soldiers during their actual military service; employees of health care institutions where biomedical research is conducted, subordinate to the researcher;

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Multimodal physiological monitoring and cerebral autoregulation monitoring|Patients are monitored routinely during their treatment in ICU. Multimodal physiological monitoring include continuous monitoring of arterial blood pressure (ABP), intracranial pressure (ICP) (if available), ETCO2 (if available), cerebral perfusion pressure (if available), cerebral blood flow velocity (CBFV) and ECG. Non-invasive cerebral autoregulation index Mx will by calculated as a Pearson correlation coefficient between slow ABP and slow CBFV waves. Invasive cerebral autoregulation index (Pressure reactivity index PRx) will by calculated as a Pearson correlation coefficient between slow ABP and slow ICP waves. Non invasive CBFV will be measured by using TCD device DWL Multi Dop-T. Invasive ICP will be measured by using Codman ICP Express or Raumedic ICP monitor.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cerebral autoregulation index (pressure reactivity index PRx) | Negative values of cerebral autoregulation index (PRx<0) represent intact cerebral autoregulation, positive values (PRx>0) show impaired cerebral autoregulation. | PRx is measured when invasive intracranial pressure slow waves and arterial pressure slow waves are available during multimodal clinical data collection in ICU (up to 7 days). | 
| Cerebral autoregulation index (mean flow index Mx) | Negative values of cerebral autoregulation index (Mx<0) represent intact cerebral autoregulation, positive values (Mx>0) show impaired cerebral autoregulation. | Mx is measured when non-invasive cerebral blood flow slow waves and arterial pressure slow waves are available during multimodal clinical data collection in ICU (up to 7 days). | 
| Optimal arterial blood pressure value | Optimal arterial blood pressure value is identified at the conditions of lowest values of cerebral autoregulation indexes by applying U-shape approximation on ABP and PRx (or Mx) data. Identified optimal arterial blood pressure value is assumed as a targeted arterial blood pressure value for personalized cerebral perfusion management in the cases when U-shape approximation is determined. | Optimal arterial blood pressure value is identified when PRx or Mx data are available during multimodal clinical data collection in ICU (up to 7 days). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patients' outcome | Patients' outcome is evaluated according to Glasgow Outcome Score (GOS). GOS scores are: 1 - death, 2 - persistent vegetative state, 3 - severe disability, 4 - moderate disability, 5 - low disability. | GOS is evaluated at discharge from hospital and after 30 days of patient's hospital admission. | 
| Occurrence of cerebral ischemia and cerebral vasospasms | Occurrence of cerebral ischemia and cerebral vasospasms evaluated from Computed Tomography (CT) and Computed Tomography Angiography (CTA) scans | CT and CTA scans is performed routinely on 7th day after SAH or within period of 3-21 day after SAH if necessary. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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optimal arterial pressure, optimal cerebral perfusion pressure, cerebral autoregulation