Fundamentals of Nursing Q 427
An elderly nursing home resident has refused to eat or drink for several days and is admitted to the hospital. The nurse should expect which assessment finding?
A. Increase blood pressure
B. Weak, rapid pulse
C. Moist mucous membranes
D. Jugular vein distention
Correct Answer: B. Week, rapid pulse
All other options are indicated by fluid volume excess. A client who has not eaten or drunk anything for several days would be experiencing a fluid volume deficit. The primary control of water homeostasis is through osmoreceptors in the brain. Dehydration, as perceived by these osmoreceptors, stimulates the thirst center in the hypothalamus, which leads to water consumption. These osmoreceptors can also cause conservation of water by the kidney. When the hypothalamus detects lower water concentration, it causes the posterior pituitary to release antidiuretic hormone (ADH), which stimulates the kidneys to reabsorb more water.
Option A: Decreased blood pressure, which often accompanies dehydration triggers renin secretion from the kidney. Renin converts angiotensin I to angiotensin II, which increases aldosterone release from the adrenals. Aldosterone increases the absorption of sodium and water from the kidney. Using these mechanisms, the body regulates body volume and sodium and water concentration.
Option C: Some of the most common presenting symptoms of dehydration include but are not limited to fatigue, thirst, dry skin and lips, dark urine or decreased urine output, headaches, muscle cramps, lightheadedness, dizziness, syncope, orthostatic hypotension, and palpitations. The physical examination could show dry mucosa, skin tenting, delayed capillary refill, or cracked lips.
Option D: A 2015 Cochrane review evaluated predictors of dehydration in the elderly. Historical and physical findings tested were dry axilla, mucous membranes, tongue, increased capillary refill time, poor skin turgor, sunken eyes, orthostatic blood pressure drop, dizziness, thirst, urine color, weakness, blue lips, altered mentation, tiredness, and appetite. Of all these factors only fatigue and missed drinks between meals predicted the diagnosis of dehydration.