Advanced Patient Assessment Practice Exam

In cases of severe dehydration, which parameter is most likely to decrease?

1. Urine osmolality

2. Blood pressure

3. Blood volume

4. Heart rate

The correct answer is: Blood pressure

In cases of severe dehydration, blood pressure is most likely to decrease. When a person becomes severely dehydrated, there is a significant reduction in the volume of circulating blood, which can lead to a drop in blood pressure. The body typically attempts to compensate for this decreased blood volume by increasing heart rate and directing blood flow to vital organs. Blood volume naturally decreases due to fluid loss, and while urine osmolality typically increases in dehydration due to the kidneys concentrating urine, blood pressure will notably decline. Heart rate may also increase as the body compensates for lower blood volume and pressure. Thus, the decrease in blood pressure is a critical indicator of the severity of dehydration and the body’s compensatory mechanisms in response to it.