This was not a smooth process. The rise of executive power sometimes hurt important interests and always rubbed against the republican sensibilities that Americans inherited from the founders. From time to time, Congress reaped political benefits from thwarting the president. But today Congress reacts rather than leads.
1 Dehydration can sometimes cause blood pressure to drop. 2  However, dehydration does not automatically signal low blood pressure. 3  Fever, vomiting, severe diarrhea, overuse of diuretics and strenuous exercise can all lead to dehydration, a potentially serious condition in which your body loses more water than you take in.
A pulse pressure is considered abnormally low if it is less than 25% of the systolic value. The most common cause of a low (narrow) pulse pressure is a drop in left ventricular stroke volume.In trauma a low or narrow pulse pressure suggests significant blood loss (insufficient preload leading to reduced cardiac output).If the pulse pressure is extremely low, i.e. 25 mmHg or less, the cause may be low stroke volume, as in Congestive Heart Failure and/or shock.A narrow pulse pressure is also caused by aortic valve stenosis and cardiac tamponade. pulse pressure is considered abnormally low if it is less than 25% of the systolic value. The most common cause of a low (narrow) pulse pressure is a drop in left ventricular stroke volume.