The brain and spinal cord can be affected by a variety of conditions related to the vascular system:
Ischemic stroke: lack of blood flow to a portion of the brain (or more rarely the spinal cord)
Intracranial or spinal hemorrhage at five possible sites:
Epidural hematoma: between the skull or spine and dura
Subdural hematoma: between the dura and arachnoid
Subarachnoid hemorrhage: between the arachnoid and brain or spinal cord
Intraparenchymal (intracerebral) hemorrhage: in the brain itself (or less commonly hemorrhage into the spinal cord (hematomyelia))
Intraventricular hemorrhage (within the ventricular system of the brain)
Cerebral venous sinus thrombosis
Vasculopathies, including vasculitis and reversible cerebral vasoconstriction syndrome (RCVS)
OVERVIEW OF ISCHEMIC STROKE AND INTRACEREBRAL HEMORRHAGE
The term stroke refers to the clinical scenario in which a patient is “struck” by a sudden-onset neurologic deficit localizable to the brain (or more rarely the spinal cord; see “Vascular Diseases of the Spinal Cord”). The vascular conditions that are collectively referred to as stroke (or cerebrovascular accident) include ischemic stroke and intracerebral hemorrhage. Intracerebral hemorrhage is sometimes referred to as “hemorrhagic stroke.” Although subarachnoid hemorrhage is sometimes included as a cause of stroke, its clinical presentation and management are distinct from ischemic stroke and intracerebral hemorrhage. Although both ischemic stroke and intracerebral hemorrhage can present similarly, their management differs. Although the potential etiologies of ischemic stroke and intracerebral hemorrhage overlap, there are unique causes of each that must be considered.
Ischemic stroke and intracerebral hemorrhage both present with sudden-onset focal neurologic deficits, but intracerebral hemorrhage is more commonly accompanied by headache, nausea/vomiting, and depressed level of consciousness at onset due to increased intracranial pressure and brain displacement from mass effect of the hematoma. However, ischemic stroke may also present with headache, nausea/vomiting, and/or depressed level of consciousness depending on the size and location of the area of ischemia, so distinction between ischemic stroke and intracerebral hemorrhage often cannot be made on clinical grounds alone. Therefore, a CT scan is necessary for diagnosis as soon as stroke is suspected.
Acute management of ischemic stroke and acute management of intracerebral hemorrhage share many aspects of supportive care but differ with respect to two parameters: coagulation and blood pressure (Table 19–1). In acute ischemic stroke, the goals are to decrease thrombosis (thrombolysis, antiplatelet agents, or in some instances anticoagulation) and allow autoregulation of blood pressure (to restore/maintain tissue perfusion). In acute intracerebral hemorrhage, the goals are to stop bleeding (reversal of anticoagulation, administration of clotting factors) and reduce blood pressure (to decrease the likelihood of hematoma expansion).
TABLE 19–1Comparison of Acute Management of Ischemic Stroke Versus Intracerebral Hemorrhage. ||Download (.pdf) TABLE 19–1 Comparison of Acute Management of Ischemic Stroke Versus Intracerebral Hemorrhage.
|Reduce (thrombolysis, antiplatelets)
|Permissive hypertension (autoregulation)