Intracranial Aneurysm

INTRACRANIAL ANEURYSM INTRACRANIAL ANEURYSM • •

Also called Cerebral Aneurysm Localized dilatation of a cerebral artery resulting from weakness in the arterial wall

CAUSES • • • • •

Atherosclerosis Congenital defect of vessel wall Hypertensive vascular disease Head trauma Advancing age

RISK FACTORS • • • • • • •

Smoking HTN Previous family history CT disorder Older age Females Over 40 y/o

PATHOPHYSIOLOGY • •

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Artery enlarges, presses on surrounding cranial nerves of brain tissue Aneurysm ruptures, causing subarachnoid hemorrhage o Normal brain metabolism disrupted by brain being exposed to blood o Increased ICP due to blood occupying space – sudden entry o Ischemia from reduced perfusion and vasospasm o Most occur at the Circle of Willis and look like berries 10-20cc bleed 50cc Massive bleed

CLINICAL MANIFESTATIONS • • • • • • •

Sudden, Very severe headache – “worst headache ever had” Loss of consciousness Nuchal rigidity – Pain and rigidity in back of neck and spine o Meningeal Irritation Visual disturbances, visual loss, diplopia, ptosis o Aneurysm adjacent to oculomotor nerve Tinnitus, dizziness, hemiparesis Aneurysm may leak blood, clot off and have no symptoms May have 50% mortality from subarachnoid hemorrhage

Prognosis depends on: Neurologic condition, age, any associated diseases, and extent / location of aneurysm

Major Threats: Initial bleed, Rebleed, Vasospasm

DIAGNOSTIC TESTS • • •

CT Scan o Shows location/size, information about affected artery, vessels, vascular branches Cerebral angiography Lumbar Puncture o Only if no evidence of Increased ICP(Danger of herniation) and CT scan is negative – confirm hemorrhage by the blood in the LP

MEDICAL MANAGEMENT •

Recover From Initial Bleed o Is the goal of treatment – Stable enough for surgery o Stages of Aneurysms 1-3 are OK and 4,5 are pretty bad ??????????

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Prevent Rebleeding o Minimize risk o 3-11 days with peak on 7th day they are at high risk for rebleed o May be given Amicar to prevent rebleed. Amicar is a Antifibronolytic  Cannot give if clotting problems

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Control Vasospasm o When the aneurysm ruptures it releases certain substances that cause vasospasm o Resulting in cerebral ischemia due to decreased blood flow o Death/disability;  headache,  LOC or new deficit o Risk for Vasospasm peaks on 7th day o Nemotop (CCB) is given to prevent vasospasm. Not when a vasospasm is occurring  Monitor for  LOC – May signal that a vasospasm is occurring  CCB Lowers BP and if you have a vasospasm---nothing is happening 

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When a person has a vasospasm they want the BP to be higher, so maybe given a medication to elevate the BP, (Dopamine, Fluid Volume Expanders) Keep the blood flowing

Treat Acute Hydrocephalus o Results when free blood obstructs reabsorption of CSF o CT Scan will show dilated ventricles with temporary shunt, sign  LOC; drain temporary

MEDICAL CARE Drug Therapy •

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Steroids Osmotic Diuretics Antihypertensives Antipyretics Stool Softeners Anticonvulsants Sedatives Antifibrinolytic Agent (Amicar)

Surgical Management • • • •

Aneurysm clip o Before rupture ASAP Trapping of aneurysm o Clipped above and below the aneurysm o You would need good collateral circulation Wrapping of aneurysm o Reinforcement, induce scarring Interventional Neuroradiology o Perform lab; small coils to solidify and prevent rebleeding; cath through femoral artery o Home within 24 hours

NURSING PLAN OF CARE •

SUBARACHNOID PRECAUTIONS – Same as  ICP o Airway o Neuro and VS checks o Bed rest with limited activity o Dark, quiet private room – NO TV or Phone o Elevate HOB 20-30 degrees or keep flat (depends on MD) o Turn every 2 hrs – Deep breathe, ROM o No external stimuli o Visitors restricted o Light sedation or analgesic – NO Narcotics, or Sedatives – Codeine & Tylenol are OK o No coughing, sneezing, straining (valsava) o No enemas, Give stool softeners o Safety measures o Anti-embolism stockings o DO not restrain o I&O; avoid overhydration o Seizure precautions

DANGER SIGNALS • • •

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 LOC Unilateral enlarged pupil Onset of hemiparesis  BP,  Pulse Sudden new headache

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Renewed nuchal rigidity; Renewed vomiting