Question 1

Which of the following best describes the role of the bicarbonate buffer system in the blood?

Accepted Answer

It buffers extracellular fluid by converting strong acids and bases into weak acids and bases.

Question 2

A patient presents with the following arterial blood gas values: pH = 7.30, pCO2 = 50 mmHg, HCO3- = 26 mEq/L. What is the most likely diagnosis?

Accepted Answer

Respiratory acidosis without compensation

Question 3

Which equation correctly calculates the anion gap?

Accepted Answer

$$\mathrm{Anion\ Gap} = [\mathrm{Na}^+] - ([\mathrm{Cl}^-] + [\mathrm{HCO}_3^-])$$

Question 4

Which of the following is a cause of high anion gap metabolic acidosis?

Accepted Answer

Methanol poisoning

Question 5

What is the effect of hypoventilation on blood pH and why?

Accepted Answer

It decreases blood pH by increasing CO2 retention, leading to respiratory acidosis.

Question 6

Which buffer system is most important for buffering the pH of intracellular fluid?

Accepted Answer

Phosphate buffer system

Question 7

A patient with a history of vomiting presents with pH = 7.48, pCO2 = 48 mmHg, HCO3- = 30 mEq/L. What is the most likely acid-base disturbance?

Accepted Answer

Metabolic alkalosis with respiratory compensation

Question 8

Which of the following best explains why proteins are effective buffers in both intracellular and extracellular fluid?

Accepted Answer

Proteins are amphoteric, meaning they can act as both acids and bases.

Question 9

Which of the following is a physiological response to metabolic acidosis?

Accepted Answer

Increased respiratory rate to blow off CO2

Question 10

A patient has the following lab values: [Na+] = 140 mEq/L, [Cl-] = 110 mEq/L, [HCO3-] = 20 mEq/L. Calculate the anion gap and determine if it is normal.

Accepted Answer

Anion gap = 10 mEq/L; normal

Question 11

Which renal mechanism is responsible for generating new bicarbonate ions during acidosis?

Accepted Answer

Type A intercalated cells secrete H+ into the filtrate and move HCO3- into the blood

Question 12

Which of the following is a likely cause of normal anion gap metabolic acidosis?

Accepted Answer

Diarrhea

Question 13

What is the effect of a decrease in blood pH on calcium levels and neuromuscular excitability?

Accepted Answer

Blood Ca++ increases, leading to CNS depression

Question 14

Which of the following best describes the compensation for respiratory alkalosis?

Accepted Answer

The kidneys excrete more HCO3- and reabsorb more H+

Question 15

A patient with chronic kidney failure is most likely to develop which acid-base disturbance?

Accepted Answer

High anion gap metabolic acidosis

Question 16

Which of the following statements about the phosphate buffer system is correct?

Accepted Answer

It is most effective in intracellular fluid and renal tubular fluid.

Question 17

Which of the following is a direct effect of acetazolamide on renal acid-base handling?

Accepted Answer

It inhibits carbonic anhydrase, reducing HCO3- reabsorption.

Question 18

Which of the following best explains why the kidneys are essential for long-term acid-base balance?

Accepted Answer

They excrete fixed acids and regenerate chemical buffers, providing a permanent solution.

Question 19

A patient with a panic attack is hyperventilating. What acid-base disturbance is most likely to occur?

Accepted Answer

Respiratory alkalosis

Question 20

Which of the following is true regarding the normal range for arterial blood pH?

Accepted Answer

$$7.35 - 7.45$$

Fluid, Electrolyte, and Acid-Base Balance: Buffer Systems and Clinical Acid-Base Disorders

Study Guide - Practice Questions

Study Guide - Flashcards