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Key
Clinical Questions Case
Outcome Optimizing
the Treatment of Cerebral Case
Presentation
Key Clinical Questions and Learning Points What
are the most common etiologies, locations, and symptoms of ICH? Putamen-Contralateral hemiparesis, contra lateral sensory loss, contra lateral conjugate gaze paresis, aphasia, neglect Thalamus-Contra lateral sensory loss, contra lateral hemiparesis, gaze paresis, miosis, aphasia or confusion Lobar-Contalateral hemiparesis or sensory loss, contra lateral gaze paresis, aphasia, neglect, or apraxia Caudate nucleus-contra lateral hemiparesis, contra lateral gaze paresis, confusion Brain stem-facial weakness,
decreased level of consciousness, gaze paresis, miosis, Cerebellum-Ataxia, ipsilateral facial weakness, ipsilateral sensory loss, gaze paresis, miosis, decreased level of consciousness The best diagnostic test in the Emergency Department is a CT scan.
The goals of blood pressure
management should be based on individual factors such as previous hypertension,
and increased intracranial pressure. In treating blood pressure the physician
is balancing two opposing theories. On the one hand elevated blood pressure
needs to be lowered to decrease the ongoing bleeding of small arterioles
which is increasing the volume of the hemorrhage, and possibly worsening
the outcome. Conversely, overaggressive treatment of blood pressure may
decrease cerebral perfusion pressure and lead to increased brain injury.
What are the optimal strategies for managing ICP? ICP is a major contributor to mortality after ICH, so controlling it is considered essential. The therapeutic goal for elevated ICP is an ICP < 20 mm Hg, and a cerebral perfusion pressure > 70 mm Hg. Managing elevated ICP can be done in several way including intubation, osmotherapy, blood pressure management, and surgery. Elevating the head of the bed to 30 degrees is one of the simplest ways to decrease ICP. The patient may be intubated for airway protection and to monitor the PCO2 which should be kept between 30-35. Although lowering the PCO2 to improve outcome has not definitely been proven, it acutely lowers ICP by cerebral vasoconstriction. Sedation and paralytic agents may be added to an intubated patient. These will prevent the patient from increasing intrathoracic and venous pressures associated with coughing, suctioning, or “bucking” the vent and raising ICP. Nondepolarizing agents such as Vecuronium or Pancuronium are the preferred agents. Osmotic diuresis with Mannitol should be given. If the above measures are unsuccessful, an induced barbiturate coma or therapeutic hypothermia may be tried. Both work by reducing cerebral blood flow and volume. Barbituate coma and hypothermia should be viewed as last ditch efforts and not part of a standard algorithm. If there is the expertise available, an ICPmonitor should be placed to directly measure the ICP. It is recommended that an ICP monitor should be place in patients with a GCS of < 9, and all patients whose condition is thought to be deteriorating secondary to an elevated ICP.
What other ICH treatments
are available to the ED physician?
Surgical candidates include: (1) Cerebellar hemorrhage > 3 cm who are deteriorating or who have brain stem compression and hydrocephalus from ventricular obstruction, (2) Vascular malformation if the lesion is surgically accessible and the patient has a chance for a good outcome, and (3)young patients with a moderate or large lobar hemorrhage who are clinically deteriorating. Patients with small hemorrhages <10 cm3, or minimal neurological deficits may be managed medically. Patients with a GCS less than 4 should be treated medically because they either die or have extremely poor functional outcome that cannot be improved by surgery.
The old concept of ICH is that the bleeding was completed in a few minutes. Recently this concept has changed. It is now felt that bleeding occurs over several hours. It is the continued bleeding that may lead to poor neurological outcome. A few studies have been published regarding increases in hemorrhage volume with a prospective study by Brott; Early Hemorrhage Growth in Patients with Intracerebral hemorrhage: published in the journal Stroke in 1997. The article found that hemorrhages grew about 33% in at least 38% of the patients in the first 24 hours. The conclusion was that substantial early hemorrhage growth in patients with ICH is common and associated with neurological deterioration. There have been other studies with similar results.
Annually, more than 20,00o
people in the United States die of an intracranial hemorrhage, with the
30 day mortality rate about 50%. The American Heart Association published
practice guidelines in 1999 for the management of ICH. In the guidelines
they emphasized a desperate need for randomized controlled trials. With
the emergence of the concept of increased volume of hemorrhage as a cause
of neurological deterioration in ICH, a therapy to decrease bleeding is
being studied. There is a phase II study showing that Factor rVIIa (commonly
used in Hemophilia) is safe to give in the setting of ICH, and may limit
bleeding and therefore the size of an ICH. A phase III trial is needed
to elucidate if Factor rVIIa has a role in the management of ICH.
Patient
Case Outcome Patient Outcome
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