Question 1

Causes of respiratory acidosis include:

Accepted Answer

Respiratory acidosis is caused by the retention of carbon dioxide (CO2) due to inadequate breathing, which can be caused by conditions such as pneumonia that make it harder to breathe. Vomiting can cause metabolic alkalosis, not respiratory acidosis. Hyperventilation leads to respiratory alkalosis, not respiratory acidosis. An increase in noncarbonic acids may result in metabolic acidosis but not respiratory acidosis.

Question 2

A 19-year-old male presents to his physician complaining of restlessness, muscle cramping, and diarrhea. Lab tests reveal that he is hyperkalemic. Which of the following could have caused his condition?

Accepted Answer

Acidosis can cause hyperkalemia because hydrogen ions move into cells to buffer the acidosis, causing potassium ions to move out of cells into the blood, increasing serum potassium levels.

Question 3

Which of the following conditions is commonly associated with hyperkalemia and metabolic acidosis?

Accepted Answer

Renal failure can lead to impaired excretion of potassium, leading to hyperkalemia. In addition, the kidneys play a role in the regulation of acid-base balance, so renal failure can also lead to metabolic acidosis.

Question 4

Which of the following would most likely cause hypochloremia?

Accepted Answer

Increased bicarbonate levels in the blood can lead to an excess of negative charges, which can cause chloride ions to shift out of the blood and into cells, leading to hypochloremia.

Question 5

Physiologic pH is maintained around 7.4 because carbonic acid and bicarbonate exist in a ratio of:

Accepted Answer

The physiologic pH of 7.4 is maintained by the bicarbonate buffer system, where the ratio of bicarbonate (HCO3-) to carbonic acid (H2CO3) is approximately 20:1.

Question 6

Acute compensation for metabolic acidosis includes:

Accepted Answer

During metabolic acidosis, the body compensates by increasing ventilation in order to decrease carbon dioxide levels and increase pH. This is known as respiratory compensation. Kidney excretion of hydrogen ions (H+) and retention of bicarbonate ions (HCO3-) is a form of chronic compensation. Retention of vitamin B12 or aldosterone secretion is not known to be a compensatory mechanism for metabolic acidosis.

Question 7

Chronic compensation for respiratory acidosis includes:

Accepted Answer

Chronic compensation for respiratory acidosis involves the kidneys excreting hydrogen ions (H+) and reabsorbing bicarbonate ions (HCO3-); this is represented by the equation: H+ + HCO3- -> H2CO3 -> CO2 + H2O. Therefore, choice A is the correct answer as it represents the correct ions that the kidneys excrete when compensating for respiratory acidosis. Choices B, C and D are not correct as they do not represent the correct compensation mechanism for respiratory acidosis.

Question 8

One cause of metabolic alkalosis is:

Accepted Answer

Excessive loss of Cl^- (chloride) can lead to metabolic alkalosis as it causes an increase in bicarbonate levels in the blood. This can occur with conditions such as prolonged vomiting or the use of diuretics. Retention of metabolic acids, hypoaldosteronism, and hyperventilation can all lead to metabolic acidosis, not alkalosis.

Question 9

A 60-year-old female is diagnosed with hyperkalemia. Which of the following would be an expected symptom?

Accepted Answer

Hyperkalemia can lead to oliguria due to its effects on the kidneys and potential for causing renal impairment.

Question 10

Which of the following buffer pairs is considered the major plasma buffering system?

Accepted Answer

The bicarbonate (HCO₃)/carbonic acid (H₂CO₃) buffer system is the primary buffer system in plasma, helping to maintain pH balance in the blood.

Question 11

Regulation of acid-base balance through removal or retention of volatile acids is accomplished by the:

Accepted Answer

The lungs regulate acid-base balance by removing or retaining carbon dioxide, a volatile acid, through respiration.

Question 12

A 55-year-old female presents to her physician complaining of dizziness, confusion, and tingling in the extremities. Blood tests reveal an elevated pH, decreased PCO₂, and slightly decreased HCO₃^-. Which of the following is the most likely diagnosis?

Accepted Answer

The elevated pH and decreased PCO2 indicate respiratory alkalosis. The slightly decreased HCO3- suggests renal compensation.

Question 13

A 54-year-old male with a long history of smoking complains of excessive tiredness, shortness of breath, and overall ill feelings. Lab results reveal decreased pH, increased CO₂, and normal bicarbonate ion. The most likely diagnosis is:

Accepted Answer

The symptoms of excessive tiredness and shortness of breath, along with the lab results of decreased pH (indicating acidosis) and increased CO₂ (a measure of carbon dioxide), suggest that the patient is experiencing respiratory acidosis. This condition is often seen in individuals with chronic obstructive pulmonary disease (COPD), such as those with a long history of smoking. The normal bicarbonate ion level suggests compensation by the kidneys to try and correct the acidosis.

Question 14

Long-term potassium deficits result in damage to the:

Accepted Answer

Long-term potassium deficits can cause damage to the kidneys, leading to renal failure. Potassium is important for maintaining the proper function of the kidney tubules, and a deficiency can lead to tubular damage and eventual loss of kidney function. Potassium deficits can also cause damage to the gastrointestinal tract and the central nervous system, but the primary organ affected in the long term is the kidneys. Lungs are not directly affected by potassium deficits.

Question 15

A 42-year-old female presents to her physician complaining of muscle weakness and cardiac abnormalities. Laboratory tests indicate that she is hypokalemic. Which of the following could be the cause of her condition?

Accepted Answer

Primary hyperaldosteronism can cause excessive secretion of aldosterone, resulting in hypokalemia, muscle weakness, and cardiac abnormalities. Respiratory acidosis, constipation, and hypoglycemia are not directly related to hypokalemia.

Question 16

Which of the following would result in hyperkalemia?

Accepted Answer

Acute acidosis can lead to hyperkalemia because hydrogen ions enter cells in exchange for potassium ions, causing an increase in extracellular potassium levels.

Quiz 4: Fluids and Electrolytes, Acids and Bases