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CHAPTER 84: Cerebrovascular Disease 775

recurrence. 54,55 Studies of acute anticoagulation are not available. Acute weeks, deteriorate due to rebleeding, hydrocephalus, or delayed isch-
anticoagulation of spontaneous or traumatic dissections of the carotid or emic deficits caused by vasospasm. Management can be complicated
vertebral arteries is often recommended. Data to support this approach by spontaneous volume contraction, cardiac and pulmonary dysfunc-
are derived only from small nonrandomized, nonblinded studies, and tion, electrolyte abnormalities, infections, and a catabolic state. The
even these data are weak. 56 treatment team should include neurosurgeons, radiologists, anesthe-
■ INTRACEREBRAL HEMORRHAGE siologists, intensivists, and nurses experienced in the management of
SAH patients. Because of the complicated nature of their surgical and
Supportive care of patients with primary intracerebral hemorrhage medical management, SAH patients are best cared for in centers that
(ICH) requires attention to the same basic factors as for patients specialize in this care.
with cerebral infarction. Any underlying coagulopathy should be cor- The management of patients following rupture of intracranial aneu-
rected as rapidly as possible. No randomized trials on management of rysms has changed significantly over the past decades. The calcium
warfarin-associated ICH have been carried out. Prothrombin complex channel blocker nimodipine is now routinely used to reduce the impact
concentrates, recombinant factor VIIa, and fresh frozen plasma alone of vasospasm. Attempts at early obliteration of the ruptured aneurysm
or in combination have all been recommended. Fresh frozen plasma with surgical clipping or endovascular placement of detachable coils
57
administration may cause pulmonary edema. Early use of Factor VIIa within the aneurysm have become routine. Hemodynamic augmenta-
58
in patients with normal hemostasis resulted in a small reduction in clot tion is now the cornerstone of the management of vasospasm with
expansion but no difference in clinical outcome. Prophylaxis for deep adjunctive endovascular treatment employed in selected cases. New
59
venous thrombosis with low-dose subcutaneous heparin or heparinoids and promising therapies that specifically target the underlying cause or
may be instituted safely on or after the second day posthemorrhage and direct effects of cerebral vasospasm are currently under investigation. 77
reduces subsequent deep venous thrombosis if begun before day 4. 60,61 Initial Stabilization and Evaluation: Initial evaluation should assess air-
Systemic blood pressure is often elevated acutely, sometimes to very way, breathing, circulation, and neurologic function. Patients with a
high levels. In patients with systolic blood pressure of 150 to 220 mm Hg, diminished level of consciousness often have impaired airway reflexes.
a randomized trial has demonstrated that rapid pharmacological reduc- In general, patients with a Glasgow Coma Scale score of 8 or less should
tion of systolic pressure by 27 mm Hg within the first hour was safe in be intubated. This should be performed under controlled conditions by
that it resulted in equivalent clinical outcomes when compared to a experienced personnel using a rapid sequence protocol. Premedication
lesser decrease of 13 mm Hg. There are insufficient data to permit des- with short-acting agents such as propofol or etomidate should be used
62
ignation of any target blood pressure levels as effective. 27,63 to prevent elevations in blood pressure (BP) with tracheal stimulation in
Clinically evident seizures are more common with lobar ICH com- order to minimize the risk of rebleeding.
pared to basal ganglia hemorrhage. Prolonged electroencephalographic As soon as the patient is stabilized, a complete neurologic examina-
64
monitoring shows electrical epileptiform events without motor convul- tion, head CT, and, if indicated, lumbar puncture should be performed.
sions in 20% to 30% of patients with acute ICH. 65,66 The value of treating Patients are graded on the basis of clinical and radiographic criteria. The
the electrographic events is under study. Prophylactic anticonvulsant two common clinical grading scales that are predictive of outcome are
treatment does not prevent seizures and may worsen outcome. 67,68 the Hunt-Hess scale and the World Federation of Neurological Surgeons
The value of ICP monitoring and treatment remains unknown. scale (Table 84-3). The Fisher Scale is based on the amount of blood
Neither mannitol nor corticosteroids reduce morbidity and mortality. visible on CT scan and is predictive of cerebral vasospasm. 78
69
Although the area of perihematomal edema on CT or MRI increases in
the several weeks following ICH, this growth is not associated with early
clinical deterioration or worse eventual outcome. 70-72 Ventriculostomy
is of unproven value as observational studies have shown no benefit. 73,74
The efficacy of ventriculostomy in combination with instillation of TABLE 84-3 The Hunt-Hess, the World Federation of Neurologic Surgeons,
and the Fisher Scales
thrombolytic drugs is currently under study in patients with intraven-
tricular hemorrhage. 75 Hunt-Hess Scale
The value of surgery is best accepted for cerebellar hemorrhages Grade Criteria
resulting in brain stem compression, although no data other than anec-
dotal reports are available. Ideally such surgical intervention should be I Asymptomatic or mild headache
undertaken before brain stem damage occurs. Patients with small cere- II Moderate to severe headache, nuchal rigidity, with or without cranial nerve deficits
bellar hematomas (<2 cm) may do well without surgical intervention, or III Confusion, lethargy, or mild focal symptoms
simply with ventricular drainage for hydrocephalus. Those with larger
cerebellar hematomas usually undergo surgical evacuation, although IV Stupor and/or hemiparesis
no prospectively validated criteria for the necessity and the timing of V Comatose and/or extensor posturing
cerebellar hematoma evacuation are available. Multiple randomized World Federation of Neurologic Surgeons Scale
controlled trials of patients with supratentorial ICH, either superficial
or deep, have shown no benefit from craniotomy and clot evacuation. 76 Grade Glasgow Coma Scale Score Motor Deficits
■ SUBARACHNOID HEMORRHAGE DUE TO RUPTURED I 15 Absent

INTRACRANIAL ANEURYSM II 14-13 Absent
III 14-13 Present
Aneurysmal SAH remains a devastating neurologic problem, with a IV 12-7 Present or absent
mortality rate of up to 45% within the first 30 days. Of those patients
that survive, more than half are left with neurologic deficits as a result V 6-3 Present or absent
of the initial hemorrhage or delayed complications. SAH presents the Fisher Scale (Based on Initial CT Appearance and Quantification of Subarachnoid Blood)
intensivist with a unique and challenging series of management issues.
SAH usually presents as an acute neurologic event that is frequently 1. No subarachnoid hemorrhage on computed tomography
followed by a series of processes leading to delayed central nervous 2. Broad diffusion of subarachnoid blood, no clots and no layers of blood greater than 1 mm thick
system and systemic complications. Patients who are minimally 3. Either localized blood clots in the subarachnoid space or layers of blood greater than 1 mm thick
affected by the initial hemorrhage can, over the course of hours to 4. Intraventricular and intracerebral blood present, in absence of significant subarachnoid blood

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