44 terms

Hemorrhagic Strokes

Ch. 62, p. 1910

Terms in this set (...)

Hemorrhagic stroke
caused by bleeding into the brain tissue, the ventricles, or the subarachnoid space
Hemorrhagic stroke etiology
-Cerebral amyloid angiopathy (elderly)
-Intracranial aneurysms or neoplasms
-Certain meds (anticoagulants, amphetamines)
Types of hemorrhagic strokes
-intracerebral hemorrhage
-intracranial (cerebral) aneurysm
-arteriovenous malformation
-subarachnoid hemorrhage
Hemorrhagic stroke patho
hemorrhage, aneurysm, or AVM presses on cranial nerves or brain tissue OR aneursym or AVM ruptures→ SAH & vasospasm→ normal brain metabolism is disrupted by brain's exposure to blood→ ↑ in ICP→↓ in cerebral perfusion→brain tissue injury or secondary ischemia
Intracerebral hemorrhage
bleeding into brain tissue commonly caused by HTN & cerebral atherosclerosis; can result from certain types of arterial pathology, brain tumors, & meds (oral anticoagulants, amphetamines, & illicit drugs)
Intracerebral hemorrhage: most common bleeding sites
-cerebral lobes
-basal ganglia
-brain stem (mostly pons)
*sometimes bleeding ruptures lateral ventricle wall & causes intraventricular bleed which is frequently fatal
Intracranial (cerebral) aneurysm
lesions usually occur at bifurcations of large arteries at the circle of Willis
Intracranial (cerebral) aneurysm: most common arteries affected by aneurysm
-internal carotid artery (ICA)
-anterior cerebral artery (ACA)
-anterior communicating artery (ACoA)
-posterior communicating artery (PCoA)
-Posterior cerebral artery (PCA)
-middle cerebral artery (MCA)
Arteriovenous Malformation
caused by an abnormality in embryonal development that leads to a tangle of arteries & veins in the brain w/o capillary beds; leads to dilation of arteries & veins & eventual rupture; most common cause of hemorrhagic stroke in young people
Subarachnoid hemorrhage (SAH)
results from an AVM, intracranial aneurysm, trauma or HTN
Most common causes of SAH
-leaking aneurysm in area of circle of Willis
-congenital AVM of brain
Hemorrhagic stroke s/s
-SEVERE headache
-early sudden change in LOC
-focal seizures (due to brain stem involvement)
-neurologic deficits seen w/ischemic strokes
S/S of Hemorrhagic stroke due to aneurysm or AVM rupture
-sudden, unusually SEVERE headache
-loss of consciousness (often)
-pain & rigidity of back/neck (nuchal rigidity) & spine (due to meningeal irritation)
-visual disturbances (visual loss, diplopia, ptosis-droopy eyelid) *Occurs if aneurysm is adjacent to CN III
Pt may show little neurologic deficit w/an anuerysm or AVM if
the blood forms a clot that seals the site of rupture
Severe bleeding due to an aneurysm or AVM results in
cerebral damage, followed rapidly by coma & death
Catastrophic event with significant morbidity & mortality
SAH from an aneurysm
Hemorrhagic stroke: Assessment & Diagnositic Findings
-CT scan or MRI (determines type of stroke, the size & location of hematoma, presence or absence of ventricular blood & hydrocephalus)
-Cerebral angiography (confirms dx of intracranial aneurysm or AVM - shows location, lesion size, & info about affected arteries, veins, adjoining vessels, & vascular branches)
-Lumbar puncture (only if no sign of ↑ ICP, CT is negative, & SAH must be confirmed)
Hemorrhagic stroke: Lumbar puncture is only performed if
-No evidence of ↑ ICP
-CT scan results are negative
-SAH must be confirmed
Lumbar puncture in the presence of ↑ ICP can result in
brain stem herniation or rebleeding
Hemorrhagic stroke prevention
-manage HTN (espec. if >55 years)
-change modifiable risk factors
Hemorrhagic stroke risk factors
-↑ age
-male gender
-excessive alcohol intake
Hemorrhagic stroke complications
-hematoma expansion
-cerebral vasospasm→cerebral ischemia
-acute hydrocephalus (results when free blood obstructs the reabsorption of CSF by arachnoid villi)
Hemorrhagic stroke complication: cerebral hypoxia & ↓ blood flow interventions
-Administer O2
-Maintain Hgb & HCT (assists w/tissue oxygenation)
-Maintain BP, CO, & cerebral blood vessel integrity
-IV fluids (ensure hydration, ↓ blood viscosity, & improve cerebral blood flow)
-Avoid HTN/hypotension extremes
-Observe for seizure activity & initiate appropriate tx
Hemorrhagic stroke complication: Vasospasm
frequently occurs 3-14 days after initial hemorrhage, when clot undergoes lysis & chance of bleeding increases
Hemorrhagic stroke: Vasospasm s/s
-worsening headache
-decrease LOC (confusion, lethargy, & disorientation)
-new focal neurologic deficit (aphasia, hemiparesis)
Hemorrhagic stroke: Vasospasms are possibly caused by
increased influx of Ca+ into cell
Hemorrhagic stroke: Vasospasm tx
-CCB: nimodipine (Nimotop)
-Triple-H therapy: fluid volume expanders, induced arterial hypertension, & hemodilution
-Endovascular techniques (used in selected pts to occlude artery supplying aneurysm w/a balloon, coils, or other techniques to occlude the aneurysm itself)
Hemorrhagic stroke complication: Increased intracranial pressure interventions
-CSF drainage via VCD
-Mannitol (monitor for dehydration & electrolyte imbalances)
-Elevate HOB
-hyperosmolar therapy
Hemorrhagic stroke complication: HTN
most common cause of intracerebral hemorrhage & treatment is critical
Hemorrhagic stroke complication: HTN interventions
-BP mgmt (individualized for each pt)
SBP may be lowered to prevent hematoma enlargement
-Elevated BP=antihypertensives: labetalol (Trandate), nicardipine (Cardene), nitroprusside (Nitropress), hydralazine (Apresoline)
-Arterial hemodynamic monitoring
-Stool softener
Hemorrhagic stroke complication: Hydrocephalus
-can occur w/i first 24h (acute) after SAH or several days (subacute) to several weeks (delayed) later
Hemorrhagic stroke complication: seizure interventions
-maintain patent airway
-prevent injury
-phenytoin (Dilantin)
Hemorrhagic stroke complication: acute hydrocephalus s/s & tx
-sudden onset of stupor or coma
-managed w/ventriculostomy drain to ↓ ICP
Hemorrhagic stroke complication: subacute & delayed hydrocephalus s/s & tx
-gradual onset of drowsiness
-behavioral changes
-ataxic gait
-ventriculoperitoneal shunt surgically placed to treat
Hemorrhagic stroke medical mgmt goals
-allow brain to recover from initial insult (bleeding)
-prevent or minimize risk of rebleeding
-prevent/treat complications
Hemorrhagic stroke: medical mgmt
-bed rest w/sedation to prevent agitation/stress
-vasospasm mgmt
-fresh frozen plasma & Vit. K (if bleeding is caused by anticoagulation w/warfarin (Norm. INR=1; Therapeutic 2-2.5)
-Antiseizure agents (seizures can occur after intracerebral hemorrhage)
-Analgesics (for head/neck pain)
-SCDs (prevent DVT)
-Insulin (hyperglycemia)
NOT treated surgically
primary intracerebral hemorrhage
Surgical evacuation is strongly recommended for pts w/a cerebellar hemorrhage if
-hematoma diameter > 3cm
-Glascow Coma Scale score decreases
Surgical tx of intracranial aneurysm is done when
pts condition is considered stable
Surgical tx of unruptured aneurysm is
Less invasive endovascular procedures to treat hemorrhagic strokes
-endovascular tx (occlusion of the parent artery)
-aneurysm coiling (obstruction of aneurysm site w/a coil)
*lower risk than intracranial surgery but can still lead to secondary complications: 2ndry stroke or aneurysm rupture
Hemorrhagic stroke: postoperative complications
-psycholocial symptoms (disorientation, amnesia, Korsakoff's syndrome, personality changes)
-Intraoperative embolization
-Postoperative internal artery occlusion
-fluid & electrolyte disturbances
-GI bleeding
Korsakoff's Syndrome
characterized by psychosis, disorientation, delirium, insomnia, & hallucinations
Most frequently used surgical evacuation for hemorrhagic strokes