Stroke Case Study Pathophysiology: In the Present

Stroke Case Study

Pathophysiology:

In the present case study, the patient is a 61-year-old male named Mr. Black. Mr. Black has presented at the Emergency Room with symptoms of stroke. Further investigation revealed a Middle Cerebral Artery (MCA) distribution stroke with substantially impacted physical function on the left side of his body. The patient also showed signs of impeded speech and reasoning abilities. According to Slater (2013), "middle cerebral artery stroke describes the sudden onset of focal neurologic deficit resulting from brain infarction or ischemia in the territory supplied by the middle cerebral artery (MCA)." (Slater, p. 1) Evidence suggests that the major contributor the Mr. Black's condition has been his chronic hypertension. Whereas many of his vital signs indicate relatively normal functionality at the time leading up to his episode, Mr. Black's blood pressure is registered at a decidedly hypertensive rate of 150/80. At 90 beats per minute, Mr. Black's pulse rate falls on the higher end of the normal function spectrum. Additionally, his respiratory rate of 20 breaths per minute also trends on the elevated end though not excessively so.

Additional consideration must be given to the presence of certain lifestyle conditions that will have contributed to Mr. Black's susceptibility to the stroke. Though Mr. Black has no family history of heart disease or stroke, his wife would report that the patient habitually smoked roughly a pack of cigarettes a day. There is a close correlation between cigarette smoking and a wide battery of serious health concerns. According to the National Stroke Association (NSA), "smoking doubles the risk for stroke when compared to a nonsmoker. It reduces the amount of oxygen in the blood, causing the heart to work harder and allowing blood clots to form more easily. Smoking also increases the amount of build-up in the arteries, which may block the flow of blood to the brain, causing a stroke." (NSA, p. 1)

In Mr. Black's case, the fact that he persisted in this habit even after beginning a hypertensive medication course ten years prior to the presenting incident would substantially undermine the effectiveness of his treatment. This case is strengthened by an otherwise normalcy in the patient's blood levels, brain imaging as well as kidney and urinary analysis. Ultimately, it may be deduced that the cigarette smoking habit contributed directly to the patient's chronic hypertension and ultimately led to the stroke resulting in Mr. Black's current hospitalization.

Explain the pathogenesis that leads to the structural and functional changes resulting from Mr. Black's stroke.

Using CT-scan imaging, we can determine to some degree the structural and functional changes that are occurring in Mr. Black's brain. Within just a few hours of the initial incident, this allows us to project the likely range of long-term neurological damage that might be resultant from the stroke. In the case of Mr. Black, the scan would reveal early ischemic changes in the left hemisphere on his brain. This suggest occlusion has occurred which has prevented the brain from properly distributing oxygen to its left hemisphere. According to Slater, "the MCA supplies most of the outer convex brain surface, nearly all the basal ganglia, and the posterior and anterior internal capsules. Infarcts that occur within the vast distribution of this vessel lead to diverse neurologic sequelae." (Slater, p. 1)

For Mr. Black, an infarction has resulted in the prevention of distribution to the left-hemisphere with evidence of potentially long-term and irreversible neurological impairment. The consequences of this clotting include a dramatic impingement on the subject's motor control as well as his speech and reasoning abilities.

Explain how two of Mr. Black's clinical manifestations are related to the structural and functional changes caused by the stroke.

Two of the most immediately evident clinical manifestations are Mr. Black's complete loss of bodily function and control on his right side and his loss of comprehensive ability. Though Mr. Black retains the ability of speech and consciousness, he remains disoriented and incapable of responding to questions with recognition or understanding. These clinical manifestations denote that the early ischemic changes (EIC) revealed by the CT-scan are connected directly to an imposing neurological impairment.

The structural implications of these impairments are described in the text by Tocco (2011). Here, the author explains that the middle cerebral artery, "feeds an enormous territory of brain, including the frontal, temporal, and parietal lobes and the brain's deep structures -- basal ganglia and internal capsule. The MCA has a main stem and several branches arising from it. Occlusion of the main stem affects the entire territory of brain supplied by the MCA" (Tocco, p. 1)

This means that the occlusion has resulted in a loss of blood-flow, and therefore oxygen, to the Basal Ganglia that impacts motor selection, Broca's Area, which impacts speech, and a number of other parts of the brain that have a critical impact on the patient's faculties. There also remains concern given the evidence at hand, of the re-occurrence of a major neurological incident in the patient. The Early Ischemic Changes demonstrated by the CT-scan invite some speculation about the threat of further incident. According to Dzialowski et al. (2006), "the Alberta Stroke Program Early CT Score (ASPECTS) semiquantitatively assesses EICs within the middle cerebral artery territory using a10-point grading system. We hypothesized that dichotomized ASPECTS predicts response to intravenous thrombolysis and incidence of secondary hemorrhage within 6 hours of stroke onset." (Dzialowski et al., p. 973) This denotes that in the case of Mr. Black, there is cause to take preventative measures or to make preparations for the possibility of hemorrhage. This may result in yet further impairment, greater permanency of the impairments already evidenced or even the patient's fatality.

Relating your discussion to the pathogenesis of Mr. Black's condition, explain the mode of action of Alteplase and Assasantin®.

In the case of most individuals suffering heart attack or stroke resulting from hypertension, heart disease, tobacco addiction on some combination of these risk factors, blood clotting is typically the culprit. This is why the far-reaching treatment capacity of Alteplase makes it a preferred drug course. According to the Mayo Clinic (2011), Alteplase is used in a wide range of clotting-derived pathologies. The Mayo Clinic reports that "Alteplase is used to dissolve blood clots that have formed in the blood vessels. It is used immediately after symptoms of a heart attack occur to improve patient survival. It is also used after symptoms of a stroke and to treat blood clots in the lungs." (Mayo Clinic, p. 1)

For Mr. Black, the first step in treatment must be addressing the clotting and occlusion where are at the root of the initial incident. This makes Alteplase the appropriate course of treatment for the patient in question.