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Cerebral Nimodipine Concentrations Following Oral, Intra-venous and Intra-arterial Administration

Recruiting
Conditions
Delayed Cerebral Ischemia
Vasospasm, Cerebral
Subarachnoid Hemorrhage, Aneurysmal
Interventions
Registration Number
NCT04649398
Lead Sponsor
Medical University of Vienna
Brief Summary

Nimodipine reduces the risk of poor outcome and delayed cerebral ischemia in patients suffering aneurysmal subarachnoid haemorrhage (SAH), but its mode of action is unknown. Its beneficial effect is assumed to be due its neuroprotective effects by reducing intracellular calcium and thereby cellular apoptosis, but higher concentrations might induce marked systemic hypotension, thereby inducing cerebral ischemia. Since several dosing regimes and routes of administration with inconclusive superiority exist and since the target site concentration of nimodipine - the unbound drug concentrations beyond the blood-brain barrier - is still not known, it is reasonable to measure nimodipine concentrations within the blood, cerebrospinal fluid (CSF) and interstitial brain tissue following oral, intra-venous and intra-arterial administration and correlate intra-arterial nimodipine administration to measures of cerebral metabolism and oxygenation.

Therefore, the investigators propose to investigate in 30 patients suffering severe aneurysmal SAH and requiring cerebral microdialysis for cerebral neurochemical monitoring:

* the ability of nimodipine to penetrate into the brain of neurointensive care patients by comparing exposure in brain, CSF and plasma, dependent on the route of administration (i.e. oral, intra-venous, and intra-arterial) and dosing intra-venously (0.5 - 2mg/h)

* the impact of orally, intra-venously, and intra-arterially delivered nimodipine on cerebral metabolism, i.e. lactate/pyruvate ratio, pbtO2 and transcranial doppler flow velocities

* the effect of oral and intra-venous nimodipine on systemic hemodynamic and cardiac parameters, using continuous Pulse Contour Cardiac Output (PiCCO) monitoring

* the penetration properties of ethanol - as an excipient of nimodipine infusion - into the brain by comparing exposure in brain, CSF and plasma and quantifying the neuronal exposure to alcohol dependent on blood levels

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
30
Inclusion Criteria
  • patient age > 18 years
  • aneurysmal subarachnoid hemorrhage
  • sedated and mechanically ventilated
  • application of brain microdialysis as standard care (due to the severity of subarachnoid haemorrhage or secondary deterioration)
  • oral, intra-venous or intra-arterial administration of nimodipine due to clinical indication
Exclusion Criteria
  • contraindication for nimodipine
  • no need of intensive care and bedside cerebral microdialysis as standard care
  • any disease considered relevant for proper performance of the study or risks to the patient, at the discretion of the investigator

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
oral nimodipineNimodipine60mg of nimodipine is orally administered every 4 h,
intra-venous nimodipineNimodipinenimodipine is continuously administered intra-venously, starting with 0.5 mg/h on day 1 and increased every day for 0.5 mg/h to a maximum dose of 2.0mg/h on day 4
intra-arterial nimodipineNimodipineduring endovascular procedure 2mg of nimodipine is infused via a microcatheter into the internal carotid artery for 20 minutes
Primary Outcome Measures
NameTimeMethod
cerebral nimodipine concentrationsduring the intervention

Area under the concentration-time curve in brain, cerebrospinal fluid and serum, dependent on the route of administration (i.e. oral, intra-venous, and intra-arterial)

cerebral ethanol concentrationsduring the intervention

Area under the concentration-time curve and maximum concentrations in brain tissue, CSF and blood after intravenous administration

Secondary Outcome Measures
NameTimeMethod
brain tissue oxygen tension (pbtO2)during the intervention for oral and intravenous administered nimodipine, 12 hours after the intervention for intra-arterial nimodipine administration

determined by cerebral parenchymal probes

extravascular lung water indexduring the intervention

measured by Pulse Contour Cardiac Output (PiCCO) monitoring

transcranial doppler flow velocitiesduring the intervention for oral and intravenous administered nimodipine, 12 hours after the intervention for intra-arterial nimodipine administration

measured in the middle cerebral artery ipsilateral to the microdialysis probe

cerebral perfusion pressureduring the intervention for oral and intravenous administered nimodipine, 12 hours after the intervention for intra-arterial nimodipine administration

measured continuously via intra-arterial and intracranial probes

fluid responsivenessduring the intervention

measured by Pulse Contour Cardiac Output (PiCCO) monitoring

cerebral lactate/pyruvate ratio (LPR)during the intervention for oral and intravenous administered nimodipine, 12 hours after the intervention for intra-arterial nimodipine administration

determined by cerebral microdialysis

angiographic vasospasmimmediately after the intervention

mild: vessel diameter from 60-99%, moderate: vessel diameter from 30-59%, severe: vessel diameter \<30% of the physiological lumen

cardiac outputduring the intervention

measured by Pulse Contour Cardiac Output (PiCCO) monitoring

systemic vascular resistance indexduring the intervention

measured by Pulse Contour Cardiac Output (PiCCO) monitoring

incidence of delayed ischemic strokes3-21 days following subarachnoid haemorrhage

ischemic strokes on CT scans

Trial Locations

Locations (1)

Medical University of Vienna

šŸ‡¦šŸ‡¹

Vienna, Austria

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