A person who breathes fast and hyperventilates may develop:

Choice A: Metabolic Acid Deficit (Metabolic Alkalosis)

Vomiting or continuous nasogastric suctioning leads to the loss of gastric contents, which are rich in hydrochloric acid (HCl)1. This loss results in a decrease in the body’s acid levels, leading to a condition known as metabolic alkalosis2. Metabolic alkalosis is characterized by an increase in blood pH due to the loss of hydrogen ions (H+) and an increase in bicarbonate (HCO3-) levels. This condition can cause symptoms such as muscle twitching, hand tremors, and light-headedness.

Choice B: Carbonic Acid Excess (Respiratory Acidosis)

Carbonic acid excess, or respiratory acidosis, occurs when there is an accumulation of carbon dioxide (CO2) in the blood, leading to a decrease in blood pH3. This condition is typically caused by respiratory issues such as hypoventilation, chronic obstructive pulmonary disease (COPD), or severe asthma. It is not directly related to vomiting or nasogastric suctioning, which primarily affect the metabolic component of acid-base balance.

Choice C: Metabolic Acid Excess (Metabolic Acidosis)

Metabolic acidosis is characterized by a decrease in blood pH due to an accumulation of metabolic acids or a loss of bicarbonate. Common causes include renal failure, diabetic ketoacidosis, and severe diarrhea. Vomiting or nasogastric suctioning, which result in the loss of gastric acid, do not lead to metabolic acidosis but rather to metabolic alkalosis.

Choice D: Carbonic Acid Deficit (Respiratory Alkalosis)

Respiratory alkalosis occurs when there is a decrease in carbon dioxide levels in the blood, leading to an increase in blood pH. This condition is often caused by hyperventilation due to anxiety, fever, or high altitude. It is not related to the loss of gastric contents through vomiting or nasogastric suctioning, which primarily affect the metabolic component of acid-base balance.

Choice A: Alkalosis

Alkalosis refers to a condition where the blood pH is higher than the normal range (above 7.45). In this case, the pH is 7.25, which indicates an acidic environment rather than an alkaline one. Therefore, alkalosis is not the correct answer.

Choice B: Respiratory

Respiratory acidosis or alkalosis is determined by the levels of PaCO2. In respiratory acidosis, PaCO2 is elevated, while in respiratory alkalosis, PaCO2 is decreased. Here, the PaCO2 is 20 mm Hg, which is below the normal range, indicating a respiratory component. However, the primary issue is not respiratory because the HCO3- is also significantly low, pointing towards a metabolic cause.

Choice C: Metabolic

Metabolic acidosis is characterized by a low pH and a low HCO3- level. In this case, the pH is 7.25, and the HCO3- is 10 mEq/L, both of which are below the normal ranges. This indicates that the primary acid-base imbalance is metabolic acidosis.

Choice D: Acidosis

Acidosis refers to a condition where the blood pH is lower than the normal range (below 7.35). The given pH of 7.25 confirms that the patient is experiencing acidosis. However, this choice alone does not specify whether it is metabolic or respiratory acidosis.

Choice E: With Compensation (Being Compensated)

Compensation refers to the body’s attempt to return the pH to normal by adjusting the levels of PaCO2 or HCO3-. In this case, the low PaCO2 suggests that there is a respiratory compensation for the metabolic acidosis. However, the primary imbalance remains metabolic acidosis.