الفهرس 
Anatomy of cerebral circulationOnly 14 pages are availabe for public view
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Abstract
Around 15 million of stroke cases occur each year worldwide causing prolonged disability than any other medical condition.
History, symptoms, examination and early recognition by FAST system are primary tools for suspecting stroke.
CT is the most commonly used Neuroimaging, the principal role is to confirm or exclude presence of hemorrhage which is a contraindication to thrombolytic therapy, antiplatelet and anticoagulation.
The most important lines of stroke management are stabilization of general condition and vital signs, adequate oxygenation and ventilation, and airway protection (aspiration pneumonia is one of the most common causes of death in stroke patient). Good hydration, prophylaxis against stress ulcer and against DVT and control brain edema or seizures are also extremely important.
Current recommendations include avoiding more than 10% reduction of BP within the first 24 hours, unless exceeds 200 mmHg systolic and 115 mmHg diastolic. Hypertension helps to maintain blood flow to the ischemic penumbra region, where cerebral autoregulation is impaired.
Thrombolytics, Antiplatelets, Anticoagulants are important to be considered in ischemic stroke.
Temperature control is a cornerstone in treatment of stroke because fever is associated with poor neurological outcome.
Hypothermia is any body temperature below 36 ºC. Therapeutic Hypothermia is induced hypothermia and can be mild (34-35.9 °C), moderate (32-33.9 °C), moderately deep (30.1-31.9 °C) or deep (less than 30 °C).
Therapeutic Hypothermia seems to be the most promising neuroprotective therapy in experimental models with encouraging results in the clinical trials.
Hypothermia acts through decreasing metabolism, reduction of Glutamate release, regulation of Inflammation, and apoptosis.
Various cooling systems are currently available. These can be roughly divided into invasive methods and noninvasive methods, with infusion of cold fluid can be used as an accessory tool in the induction phase of hypothermia. The choice of cooling systems should enable rapid induction and maintenance of temperature at the desired level within a narrow range for prolonged periods of time.
Therapeutic hypothermia can be divided into 4 phases: Induction, maintenance, de-cooling (re-warming) and normothermia.
Induction is usually achieved by infusion of cold isotonic fluid. The precautions in this phase included avoidance of over-cooling, hypokalemia, hyperglycemia, and shivering.
Therapeutic hypothermia can be maintained by many different methods, varying in their level of invasiveness, cost and effectiveness. Issues including changes in pharmacokinetics and hemodynamics, and susceptibility to infection need to be addressed. The optimal duration of maintenance is unknown but the usual practice is 12-24 hours.
De-cooling and rewarming is especially challenging because complications can be serious if temperature rise by more than 1°C every 3-5 hours, life-threatening hyperkalemia can occur especially if patient suffers from renal insufficiency.
Fever is a frequent complication either due to infection or post-cardiac arrest syndrome but patient must be kept normothermic for 72 hours.
There is no adequate information on the optimal technique of hypothermia in patients with acute ischemic stroke. On theoretical grounds, longer durations may be more effective, but these may also be less well tolerated by awake patients and may be associated with a higher risk of complications.
Patients with massive brain injuries may experience rebound intracranial hypertension when rapidly rewarmed after prolonged periods of mild to moderate hypothermia. Slow and controlled re-warming (longer than 12- hour) should be achievable.
The temperature of the body is regulated by temperature-regulating centers located in the hypothalamus. The main responses to external cold are shivering to increase heat production and vasoconstriction to decrease heat loss.
These initial responses to maintain homeostasis are detrimental to a patient in whom hypothermia is induced. Anti-shivering protocols make routine clinical use of hypothermia after ischemic stroke possible.
Finally even if hypothermia has no solid evidence of feasibility by wide trials to be used in stroke, “Temperature control is still recommended”.