Cerebral Vasospasm M. Christopher Wallace M.D. The Toronto Western Hospital, University Health Network University of Toronto Postgraduate Lecture Series

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  • Cerebral VasospasmM. Christopher Wallace M.D.The Toronto Western Hospital, University Health NetworkUniversity of Toronto

    Postgraduate Lecture Series Division of NeurosurgeryFriday October 20, 2000

  • Subarachnoid HemorrhageDelayed presentationHeadache, no deficitMinimal subarachnoid blood

  • Cause of Subarachnoid Hemorrhage?

  • Post surgical CT

  • Post-op Angiography

  • Comparison Angiograms

  • Post surgical CTs

  • History1927Moniz - angiography1937Dandy describes the clipping of intracranial aneurysm1949Robertson described post-mortem lesions after aneurysmal SAH.Brain 72:150, 19491951Ecker & Reimenschneider angiographic spasm

  • Time CourseAfter aneurysmal subarachnoid hemorrhageDelayed onsetRarely present before Day 3Peak Day 6-7

  • Significance1970sDoes it exist?Time course in humansKwak, NiizumaSurg Neurol 11:257, 1979Niizuma, Kwak Surg Neurol 11:263, 1979Cause of death or disability in 13.5% in co-operative studyJ. Neurosurgery 73:18-36, 1990

  • Vasospasm and SAHRelationship to the amount of subarachnoid hemorrhageFisher CT GradeI2/11 angiographic spasm, 0/11II0/7III23/24 clinical vasospasm

    Fisher, Kistler, Davis Neurosurgery 6:1 1980

  • EtiologyReversible?Smooth muscle contraction vs morphological change in vascular wallWeir, Findlay, MacDonaldDemonstration of role of oxyhemoglobin leads to documented contraction of smooth muscleDelayed thickening of intima and adventitia day 28

  • EtiologyFresh serum and platelet rich plasma are vasoreactiveWashed rbcs are inertContractility of rbcs linked to incubation with plasmaTrapped rbcs in subarachnoid space day 7

  • Treatment of cerebral vasospasmDiagnosisHypervolemic-hypertensive therapyCalcium channel blockersCerebral angioplastyIntracisternal thrombolytic therapy

  • Diagnosis

    Clinical suspicion:patient/time periodTranscranial dopplerCerebral angiographyNeurological deficit

  • Hypervolemic-hypertensive therapyProphylactic use of euvolemia in patients with aneurysmal hemorrhage post-therapy Kosnik & HuntJ Neurosurg 45:148, 1976Kassell, Peerless et alNeurosurgery 11:337, 1982Reversal of deficit in 43/58 patientsUse of colloids and inotropesClinical detection of deficit and angiographic proof of spasm

  • Calcium channel blockersUse of nimodipine 60mg q4h x 3 weeksReduces morbidity/poor outcomes but does not alter the incidence of angiographic spasm.?mechanismAllen NEJM 308:619, 1983Petruk J Neurosurg 68:505, 1988Pickard Br Med J 298:636, 1989

  • Cerebral angioplastyMechanical vs chemical (papaverine)Early, minimal deficit, radiological contraindicationsPermanenceRisk of rupture?prophylaxisPolin et al Neurosurgery 42:1256-1264, 1998Eskridge et al Neurosurgery 42:510-516, 1998

  • Intracisternal thrombolytic therapyCisternal clot removalLaboratory evidenceProspective study failed to demonstrate efficacyN=100, high risk patients in main centre (p=0.02) mild/no spasmseverePlacebo42%23%rt-PA69%15%

    Findlay et al Neurosurgery 37:168-176, 1995

  • Endothelin and VasospasmIsolated from endothelial cells, 1988Three isoforms:ET-1, -2, -3, 21 AAPrepro ET-1 gene, conversion to proendothelin then Big-ETET-1 most vasoactiveVasoconstriction, elevates arterial pressure, bronchoconstrictionEndothelin receptors: ETA, ETB1, ETB2Neurosurgery 43:863-876, 1998

  • Endothelin ReceptorsETAlocalized to smooth musclemediates vasoconstrictionETB1Localized to vascular endothelial cellsMediates endothelium-dependant vasodilation action of ETETB2Similar localization and action to ETA

  • Endothelin and VasospasmDocumented in CSF after aneurysmal SAHMarker vs mediatorLikely not over expression of ET1Potential for therapy with selective agonists/antagonists to receptors

  • Approach to Patient with Delayed Neurological DeficitPost-opHemorrhageIschemiaVessel occlusionClipping or coiling errorPost temporary clipping

  • Approach to Patient with Delayed Neurological DeficitDay1-3HyponatremiaFeverOxygenationHydrocephalusMedicationsRebleed/unsecured aneurysm

  • Approach to Patient with Delayed Neurological DeficitDay3-10VasospasmVasospasmVasospasmHydrocephalusFever/pneumonia

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