Question 1

Insensible water losses are those that occur as the result of water that is lost in:

Accepted Answer

Insensible water losses refer to the water lost through processes that are not easily measured, such as breathing and sweating.

Question 2

Which of the following statements is true as it relates to acid-base balance?

Accepted Answer

Renal mechanisms are slower than respiratory mechanisms in correcting acid-base imbalances, but they are more effective in the long term and continue to function until the pH is normalized.

Question 3

Which of the following is the highest priority for meeting the needs of a patient who presents with a 3-day history of vomiting and diarrhea, blood pressure of 85/60 mm Hg, heart rate of 105 beats/min, and temperature of 99°F?

Accepted Answer

The patient's low blood pressure and elevated heart rate indicate hypovolemia due to fluid loss from vomiting and diarrhea. Replacing fluid loss is the highest priority to stabilize the patient's hemodynamic status.

Question 4

Reduced capillary osmotic pressure can be caused by:

Accepted Answer

Reduced capillary osmotic pressure is primarily caused by a low concentration of plasma proteins, as these proteins are responsible for maintaining osmotic pressure in the blood.

Question 5

Which of the following signs would indicate a fluid deficit?

Accepted Answer

Tachycardia, acute weight loss, weakness, and dry mucous membranes are signs of fluid deficit, indicating dehydration or insufficient fluid in the body.

Question 6

Aldosterone's main effect is the regulation of:

Accepted Answer

Aldosterone primarily regulates sodium by increasing its reabsorption in the kidneys, which also indirectly affects water retention and potassium excretion.

Question 7

In which of the following data would acidosis be more likely?

Accepted Answer

Acidosis is often associated with hyperkalemia, which is a high level of potassium in the blood. A serum potassium level of 6.2 mEq/L indicates hyperkalemia, making acidosis more likely.

Question 8

Which of the following patients should be evaluated first?

Accepted Answer

The 52-year-old female with acute renal failure has a critically low pH indicating acidosis, high potassium (hyperkalemia), and high sodium, which are life-threatening conditions requiring immediate attention.

Question 9

Which of the following would be appropriate treatment for a patient on a ventilator with respiratory alkalosis, a low CO₂, and normal sodium bicarbonate?

Accepted Answer

Decreasing the respiratory rate on the ventilator will help retain CO2, which can correct respiratory alkalosis by allowing CO2 levels to rise back to normal.

Question 10

Classify the following arterial blood gas: pH = 7.35, PaCO₂ = 50 mm Hg, HCO₃^- = 29 mEq/L.

Accepted Answer

The pH is on the lower end of normal, indicating acidosis. The elevated PaCO2 suggests a respiratory cause, and the elevated HCO3- indicates renal compensation, making it a compensated respiratory acidosis.

Question 11

Classify the following arterial blood gas: pH = 7.52, PaCO₂ = 30 mm Hg, HCO₃^- = 24 mEq/L.

Accepted Answer

The pH is elevated, indicating alkalosis. The PaCO2 is low, which suggests that the alkalosis is due to respiratory causes, as CO2 is being blown off, leading to respiratory alkalosis.

Question 12

Which of the following would be used to treat severe hyperkalemia?

Accepted Answer

Insulin and Dextrose 50% are used to treat severe hyperkalemia by driving potassium back into cells, thereby lowering blood potassium levels.

Question 13

What fluid and electrolyte changes will occur in a patient with diabetes and a very high blood glucose?

Accepted Answer

Hyperkalemia develops, and water shifts by osmosis from the cells into the extracellular fluid (ECF).

Question 14

Respiratory acidosis occurs most commonly in:

Accepted Answer

Respiratory acidosis is most commonly associated with conditions that impair lung function and gas exchange, such as emphysema, leading to an accumulation of carbon dioxide in the blood.

Question 15

Which of the following compensatory mechanisms occur when osmolality increases?

Accepted Answer

When osmolality increases, the body stimulates the thirst mechanism to encourage water intake and also releases antidiuretic hormone to conserve water, not suppress it.

Question 16

A patient with decompensated heart failure with reduced ejection fraction has edema and shortness of breath. The patient has hyponatremia. Which of the following is the most likely cause of the hyponatremia?

Accepted Answer

In heart failure, the body retains excess water due to mechanisms like increased antidiuretic hormone (ADH) secretion, leading to dilutional hyponatremia.

Question 17

A patient just ran a marathon in extreme heat and is diagnosed with dehydration. What is an expected finding in the urine-specific gravity?

Accepted Answer

Dehydration typically leads to concentrated urine, resulting in a high urine-specific gravity.

Question 18

A patient with a history of angina and hypertension is getting a preoperative evaluation for a knee replacement. His preoperative history and physical examination revealed no abnormalities. The preoperative labs, however, reveal a serum potassium level of 5.9 mEq/L. The next intervention would be to:

Accepted Answer

A repeat serum potassium level should be drawn to confirm the hyperkalemia before initiating any treatment, as lab errors can occur.

Question 19

Which serum value can cause an abnormal total calcium levels and, if known, should be used to calculate a corrected serum calcium level?

Accepted Answer

Albumin levels can affect total calcium levels because a significant portion of calcium in the blood is bound to albumin. Therefore, when albumin levels are abnormal, a corrected calcium level should be calculated to assess the true calcium status.

Question 20

In which scenario is hypercalcemia likely?

Accepted Answer

Hypercalcemia is commonly associated with hyperparathyroidism, as the condition leads to increased secretion of parathyroid hormone, which raises calcium levels in the blood.

Quiz 6: Fluid, Electrolyte, and Acid-Base Homeostasis