Question 1

Which of the following is NOT a cause of hyperchloremic metabolic acidosis?

Accepted Answer

Methanol intoxication causes metabolic acidosis through the formation of formic acid, not through an increase in chloride levels, making it not a cause of hyperchloremic metabolic acidosis. Hyperchloremic metabolic acidosis is typically associated with conditions that lead to an excess of chloride in the body, such as hyperalimentation, severe diarrhea, or the administration of certain chloride-rich solutions, but not with methanol intoxication.

Question 2

Compensation for respiratory alkalosis occurs through which of the following?

Accepted Answer

Compensation for respiratory alkalosis involves the kidneys excreting bicarbonate in order to restore the acid-base balance in the body. The correct chemical formula for bicarbonate is HCO₃F1F1F1S1^F1F1F10, which is found in option B. Therefore, the answer is B.

Question 3

What compensates for a metabolic alkalosis?

Accepted Answer

Hypoventilation compensates for a metabolic alkalosis by retaining carbon dioxide (CO2) in the bloodstream, which increases the concentration of hydrogen ions (H+) through the reaction: CO2 + H2O → H2CO3 → H+ + HCO3-. This helps to decrease the pH and correct the alkalemia. Hyperventilation would exacerbate the alkalosis by decreasing the CO2 concentration and increasing the pH. Renal excretion of bicarbonate (HCO3-) or retention of hydrogen ions (H+) would also exacerbate the alkalosis.

Question 4

What is the treatment for severe metabolic acidosis?

Accepted Answer

The treatment for severe metabolic acidosis is to correct the underlying cause, and NaHCO3 infusion can help to correct the acidosis by raising the systemic pH level. Insulin may be helpful in cases of diabetic ketoacidosis. Mechanical ventilation may be necessary if respiratory failure is present. Charcoal is not a treatment option for metabolic acidosis.

Question 5

A patient who has fully compensated respiratory acidosis becomes severely hypoxic. If her lungs are not too compromised, what might her gases now appear to be?

Accepted Answer

The answer of A patient who has fully compensated respiratory...

Question 6

What are some causes of metabolic acidosis with an increased anion gap?
I.diarrhea
II.ketoacidosis
III.lactic acidosis
IV.renal failure

Accepted Answer

Metabolic acidosis with an increased anion gap is characterized by a higher-than-normal concentration of anions in the blood. This can be caused by the accumulation of acids such as ketoacids (ketoacidosis) and lactic acid (lactic acidosis) as well as in renal failure where there is decreased elimination of acids. Diarrhea (option I) can cause metabolic acidosis with a normal anion gap. Therefore, the correct answer is option C - II, III, and IV.

Question 7

What condition or treatment could cause iatrogenic respiratory alkalosis?

Accepted Answer

Mechanical hyperventilation can cause iatrogenic respiratory alkalosis by increasing the rate and depth of breathing, resulting in a decrease in carbon dioxide levels and subsequent increase in pH levels.

Question 8

Which of the following is NOT a cause of metabolic alkalosis?

Accepted Answer

Hyperkalemia is a cause of metabolic acidosis, not alkalosis. The other options listed are all potential causes of metabolic alkalosis. Diuretics can lead to excessive loss of water and sodium, which can cause an increase in bicarbonate levels and a shift towards alkalosis. Hypochloremia, which is a deficiency in chloride ions, can result in a decrease in acid production in the stomach and lead to alkalosis. Vomiting can cause the loss of stomach acid, leading to an increase in bicarbonate levels and metabolic alkalosis.

Question 9

Primary metabolic alkalosis is associated with which of the following?

Accepted Answer

Primary metabolic alkalosis occurs due to an accumulation of base or loss of acid, resulting in an increase in the blood pH. A gain of buffer base is one possible cause for primary metabolic alkalosis.

Question 10

Discounting K⁺, what is a normal anion gap range?

Accepted Answer

A normal anion gap range is typically considered to be 9 to 14 mEq/L. An anion gap is a laboratory test that measures the difference between positively charged ions (such as sodium and potassium) and negatively charged ions (such as chloride and bicarbonate) in the blood. An elevated anion gap can indicate a variety of conditions, including metabolic acidosis.

Question 11

A patient has a confirmed metabolic acidosis with a normal PCO₂. What inference can you draw from these findings?

Accepted Answer

A normal PCO2 in the presence of metabolic acidosis suggests that the expected respiratory compensation (hyperventilation to lower PCO2) is not occurring, indicating a possible coexisting ventilatory disorder.

Question 12

Metabolic acidosis may be caused by: I.an increase in fixed (nonvolatile) acids II.an increase in blood carbon dioxide (CO₂) III.excessive loss of bicarbonate (HCO₃^-)

Accepted Answer

Metabolic acidosis is caused by an increase in fixed (nonvolatile) acids or excessive loss of bicarbonate. Blood carbon dioxide levels do not directly cause metabolic acidosis, but an increase in CO2 levels can contribute to respiratory acidosis, which can exacerbate metabolic acidosis. Therefore, options I and III are correct, while option II is not directly related to metabolic acidosis.

Question 13

What is the kidneys' most important function?

Accepted Answer

The answer of What is the kidneys' most important function?
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Question 14

A patient with Kussmaul's respirations most likely has:

Accepted Answer

Kussmaul's respirations are deep and rapid breathing patterns that occur as a compensatory mechanism in response to metabolic acidosis. This type of breathing helps to eliminate excess CO2 and increase pH levels in the body. Therefore, the most likely cause of Kussmaul's respirations is metabolic acidosis.

Question 15

What explains the lack of an increased anion gap seen in metabolic acidosis caused by HCO₃^- loss?

Accepted Answer

The lack of an increased anion gap in metabolic acidosis caused by bicarbonate (HCO3-) loss is due to the reabsorption of chloride (Cl-) ions by the kidney for each bicarbonate ion lost, maintaining the anion balance.

Question 16

What is the main compensatory mechanism for metabolic acidosis?

Accepted Answer

The main compensatory mechanism for metabolic acidosis is hyperventilation, which leads to a decrease in carbon dioxide levels and an increase in pH, thereby compensating for the decreased pH in the blood. Option A is incorrect as excretion of HCO3- would further decrease the pH. Option C is incorrect as hypoventilation would increase carbon dioxide levels in the blood, aggravating the acidosis. Option D is incorrect, as retention of CO2 would also aggravate the acidosis.

Question 17

With partially compensated respiratory alkalosis, which of the following blood gas abnormalities would you expect to encounter? I.decreased pH II.decreased HCO₃^- III.decreased PCO₂ IV.increased pH

Accepted Answer

In partially compensated respiratory alkalosis, the primary abnormality is a decreased PCO2 due to hyperventilation, which leads to an increased pH (alkalosis). The body attempts to compensate by decreasing HCO3- (bicarbonate) levels, but since the condition is only partially compensated, the pH remains elevated, though not as high as it would be without any compensation.

Question 18

Which of the following is NOT a clinical sign of acute respiratory alkalosis?

Accepted Answer

Depressed reflexes are actually a clinical sign of respiratory acidosis, not alkalosis. The other options (convulsions, dizziness, and paresthesia) are all commonly seen in acute respiratory alkalosis.

Question 19

What would be an example of an iatrogenic cause of metabolic alkalosis?

Accepted Answer

Gastric suction can remove excessive hydrochloric acid from the stomach leading to metabolic alkalosis.

Answer: B and C 
 Hypochloremia and hypokalemia can cause metabolic alkalosis due to the loss of chloride and potassium ions respectively, which are essential for maintaining acid-base balance in the body.

Answer: D 
 Vomiting can lead to metabolic alkalosis by causing loss of hydrochloric acid from the stomach.

Question 20

A patient has an anion gap of 21 mEq/L. Based on this information, what can you conclude?
I.There is an abnormal excess of unmeasured anions in the plasma.
II.The patient probably has metabolic acidosis.
III.The concentration of fixed acids is increased.

Accepted Answer

An anion gap of 21 mEq/L is greater than the normal range (between 6 and 12 mEq/L). This indicates the presence of an abnormal excess of unmeasured anions in the plasma, which would account for the increased anion gap. This is often seen in cases of metabolic acidosis where fixed acids like lactic acid or ketones are produced, which can increase the concentration of fixed acids. Therefore, the patient probably has metabolic acidosis, and the concentration of fixed acids is increased.

Quiz 13: Acid-Base Balance