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

Medical University of Vienna

Status: Enrolling

Conditions: Subarachnoid Hemorrhage, Aneurysmal; Vasospasm, Cerebral; Delayed Cerebral Ischemia

Treatments: Drug: Nimodipine

Study type: Observational

Funder types: Other

Identifiers

NCT04649398

Brain_MD_Nimodipine

Details and patient eligibility

About

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

Enrollment: 30 estimated patients

Sex: All

Ages: 18 to 95 years old

Volunteers: No Healthy Volunteers

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

Trial design

30 participants in 3 patient groups

oral nimodipine

Description:

60mg of nimodipine is orally administered every 4 h,

Treatment:

Drug: Nimodipine

intra-venous nimodipine

Description:

nimodipine 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

Treatment:

Drug: Nimodipine

intra-arterial nimodipine

Description:

during endovascular procedure 2mg of nimodipine is infused via a microcatheter into the internal carotid artery for 20 minutes

Treatment:

Drug: Nimodipine