What are the signs of dehydration in an adult patient?

The signs of dehydration in an adult patient typically include increased thirst, dry mucous membranes, and decreased urine output. Increased thirst occurs as the body's natural response to signal the need for more fluids. Dry mucous membranes, particularly in the mouth and nose, indicate a lack of adequate moisture, which is another common physical manifestation of dehydration. Decreased urine output also signals dehydration, as the body conserves fluids when it senses a deficiency. When the body is dehydrated, it prioritizes maintaining essential functions and reduces urine production as a protective mechanism.

The other symptoms listed in the other options may not directly correlate with dehydration. For example, swelling is often associated with fluid retention rather than loss, while headache and dizziness can stem from a range of causes, not just dehydration. Weight gain, anxiety, and fatigue are also not indicative of dehydration, as they relate to different health issues. Frequent urination, increased heart rate, and high blood pressure typically suggest fluid overload or other conditions rather than the absence of adequate hydration. This reinforces the importance of recognizing the specific signs of dehydration to effectively monitor and address fluid balance in patients.