Pressure system low pressure, while As depict anticyclonic flow or likely positions of high-pressure areas. An area of confluent streamlines shows the location of shearlines within the tropics and subtropics. Pressure system A low-pressure area, or "low", is a region where the atmospheric pressure at sea level is below that of surrounding locations. Low-pressure systems form under areas of wind divergence that occur in upper levels of the troposphere. The formation process of a low-pressure area is known as cyclogenesis. Within the field of atmospheric dynamics, areas of wind divergence aloft occur in two areas: Diverging winds aloft ahead of these troughs
Pulse pressure aorta wall. 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 cardiogenic shock. A narrow pulse pressure is also caused by aortic valve stenosis and cardiac tamponade. Usually, the resting