the nurse is admitting a patient with a suspected fluid imbalance the most sensitive indicator of body fluid balance is

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Fluid and Electrolytes ATI

1. The nurse is admitting a patient with a suspected fluid imbalance. The most sensitive indicator of body fluid balance is:

A. Daily weight
B. Serum sodium levels
C. Measured intake and output
D. Blood pressure

Correct answer: A

Rationale: Daily weight is the most sensitive indicator of body fluid balance because it can show trends over time, helping in assessing the effectiveness of interventions and medications. While serum sodium levels provide objective data on electrolyte balance, they may not accurately reflect fluid balance, especially if a patient is dehydrated. Measured intake and output are crucial for assessing fluid balance, but it can be challenging to match the two due to various ways fluid is lost from the body. Blood pressure and other vital signs may not always be reliable indicators of fluid balance as they can be influenced by other factors beyond fluid status.

2. Which of the following statements is correct?

A. People with less body fat have more body water.
B. Infants have more water per pound than adults.
C. Females have more body water per pound than males.
D. Infants have the same water content per pound as adults.

Correct answer: A

Rationale: The correct statement is that people with less body fat have more body water. This is because fat tissue contains less water compared to lean tissue, so individuals with less body fat generally have a higher percentage of body water. Choice B is incorrect as infants actually have more water per pound than adults due to their higher body water content. Choice C is incorrect as males typically have more body water per pound than females. Choice D is incorrect as infants have a higher water content per pound compared to adults.

3. A patient with a longstanding diagnosis of generalized anxiety disorder presents to the emergency room. The triage nurse notes upon assessment that the patient is hyperventilating. The triage nurse is aware that hyperventilation is the most common cause of which acid-base imbalance?

A. Respiratory acidosis
B. Respiratory alkalosis
C. Increased PaCO2
D. CNS disturbances

Correct answer: B

Rationale: The correct answer is B: Respiratory alkalosis. Hyperventilation, which can be caused by extreme anxiety, is the most common cause of acute respiratory alkalosis. This leads to a decrease in PaCO2 levels. Respiratory acidosis, choice A, occurs in conditions like hypoventilation, leading to an increase in PaCO2 levels. Choice C, Increased PaCO2, is not the correct term for an acid-base imbalance related to hyperventilation. Choice D, CNS disturbances, is not directly related to the acid-base imbalance caused by hyperventilation.

4. A 73-year-old man who slipped on a small carpet in his home and fell on his hip is alert and oriented; PERRLA (pupils equally round and reactive to light and accommodation) is intact, and he has come by ambulance to the emergency department (ED). Heart rate elevated, he is anxious and thirsty. A Foley catheter is in place and 40mL of urine is present. The nurse's most likely explanation for the urine output is:

A. The man urinated prior to his arrival in the ED and will probably not need to have the Foley catheter kept in place.
B. The man has a brain injury, lacks ADH, and needs vasopressin.
C. The man is in heart failure and is releasing atrial natriuretic peptide, which results in decreased urine output.
D. He is having a sympathetic reaction, which has stimulated the renin-angiotensin-aldosterone system that results in diminished urine output.

Correct answer: D

Rationale: Renin is released by the juxtaglomerular cells of the kidneys in response to decreased renal perfusion. Angiotensin-converting enzyme converts angiotensin I to angiotensin II. Angiotensin II, with its vasoconstrictor properties, increases arterial perfusion pressure and stimulates thirst. As the sympathetic nervous system is stimulated, aldosterone is released in response to an increased release of renin, which decreases urine production. Based on the nursing assessment and mechanism of injury, this is the most likely cause of the lower urine output. Choices A, B, and C are incorrect because there is no indication of urination prior to arrival, brain injury, lack of ADH, or heart failure present in the scenario provided. The symptoms and context described point more towards a physiological response related to the sympathetic nervous system and the renin-angiotensin-aldosterone system rather than the other conditions mentioned.