the patient until the problem can be treated. Positive pressure ventilation will help improve oxygenation.
STROKE There are three major types of stroke. The ischemic stroke can be thrombotic or embolic in origin. A thrombotic stroke involves an in-situ clot in an artery that either supplies a part of the brain, such as the vertebral or carotid artery, or that is within the brain itself. An embolic stroke is similar but involves a clot that originated elsewhere in the body that traveled to the brain, occluding an artery within the brain itself. On the other hand, a hemorrhagic stroke involves a disruption of an artery of the brain itself, which bleeding into the brain. Ischemic strokes have both modifiable and nonmodifiable risk factors. The modifiable risk factors include hypertension, which is perhaps the most significant risk factor, cigarette smoking, diabetes, dyslipidemia, abdominal obesity, insulin resistance, sedentary lifestyle, alcoholism, poor dietary habits, psychological stress, such as depression, certain heart conditions, such as atrial fibrillation, myocardial infarction, and infective endocarditis, the use of cocaine or amphetamines, vasculitis, and hypercoagulability states. Nonmodifiable risk factors include advanced age, family history of stroke, and previous stroke. If an embolic stroke is anticipated, you will need to look for a possible source. The most common source is atrial fibrillation. In this case, the embolism comes from a fibrillating left atrium. Much less likely, an embolic stroke can come from a prosthetic heart valve, post-MI situation, rheumatic heart disease, bacterial endocarditis with vegetations, or a mechanical circulatory assist device, such as an LVAD. Long bone fractures can lead to fat emboli and compression sickness can lead to an air embolism. Lacunar infarcts are also ischemic strokes. These are small strokes that do not involve thrombosis but that involve degeneration of the small arteries that get replaced by collagen and lipids. The deep cortical structures are what are mostly involved in these types of strokes, with things like uncontrolled hypertension, diabetes, and old age being the most common underlying factors.
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