Hi Badri
Thanks for the review of Stroke one of the common medical problems every of us face. We know that despite all modern development in the field of medicine, we are not able to do much for stroke patients. The deeper we dwell in the subject, more depressed we become.
As you correctly mentioned hypertension is the most important factor in the causation of this malady. A few random points I want to make for the sake of junior colleagues.
Hypertension is common in patients admitted with an acute stroke, and a transient blood pressure rise can be found also in previously normotensive patients, whereas in patients with haemorrhagic stroke hypertension in the acute phase is more severe than the usual blood pressure elevation.
The appropriate management of raised blood pressure at stroke onset remains an unsolved question. In fact, blood pressure may decline spontaneously and unpredictably without intervening medications. Furthermore, the incorrect use of antihypertensive drugs in acute stroke may reduce the pressure-dependent cerebral perfusion to the ischemic penumbra, the area surrounding the ischemic necrotic core perfused by collaterals at low flow, and therefore may worsen cerebral damage.
We have noted in our practice that there are so many patients under our care who show much variability or instability in the BP recordings despite two or three drugs. Such persons who show this type of instability are prone to chronic repeated small stroke like events leading to brain atrophy, subcortical ischemic lesions and cognitive impairment. Calcium channel blockers are said to be better for these patients.
It has been known for years that blood pressure at night is typically lower than blood pressure during the day. There is a somewhat arbitrary cut-off of about 10%. If your blood pressure declines less than 10% during the night compared with what it was during the day, you are defined as a non-dipper. There is a fair amount of data that have shown that if you are a non-dipper or if your blood pressure at night remains elevated, the risks for subsequent cardiovascular disease and renal disease are higher. These variability of BP can be identified and treated only by ambulatory BP measuring devices.
Another category of patients who have risk of stroke is persons who have obstructive sleep apnoea. Experts on sleep apnoea have data showing that if you fix the sleep apnoea, you can restore dipping status in many cases, although not all of them.
The significance and best management of hypertension observed during the first hours after stroke onset are still a matter of debate. Recent guidelines recommend clinical trials to ascertain whether antihypertensive therapy in the acute phase of stroke is beneficial. This review summarizes previous reports on blood pressure management during the first 72 hours after an acute ischemic stroke and shows that a large number of papers published in the past 20 years failed to convince that early use of antihypertensives in unselected patients with acute ischemic stroke is beneficial. The authors stress that only blood pressure values repeatedly higher than 220/120 mm Hg should be gradually lowered and kept in the range of 180-220 mm Hg systolic and 100-120 mm Hg diastolic. (Ref:
http://www.medscape.com/viewarticle/473113).
UA Mohammed