Question

A nurse is caring for a client who has had prolonged vomiting, has an NG tube for gastric decompression, and is receiving total parenteral nutrition. The client's ABG results are pH7.48, PaCO2 50 mm Hg, and HCO3 30 mEq/L. Based on these findings, the nurse should identify that the client has which of the following acid-base imbalances?

A: Metabolic alkalosis
B: Metabolic acidosis
C: Respiratory acidosis
D: Respiratory alkalosis

Answer 1

The client with a pH of 7.48, PaCO2 of 50 mm Hg, and HCO3 of 30 mEq/L is experiencing metabolic alkalosis with compensatory respiratory acidosis, likely due to loss of gastric acid through prolonged vomiting.

Step-by-step explanation:

The client's ABG results showing a pH of 7.48, PaCO2 of 50 mm Hg, and HCO3 of 30 mEq/L indicate the presence of an acid-base imbalance. A normal arterial pH ranges from 7.35 to 7.45, and any value above this range suggests alkalosis. In this case, the increased pH indicates the client is experiencing alkalosis. The elevated levels of HCO3 (bicarbonate) further suggest that this is a case of metabolic alkalosis. This is because a primary increase in bicarbonate, or compensation for respiratory acidosis, typically characterizes metabolic alkalosis. However, since the PaCO2 is above normal range, indicating hypoventilation, it seems that respiratory compensation is occurring. Thus, the client displays metabolic alkalosis with compensatory respiratory acidosis.

In the context of this client, who has had prolonged vomiting and is receiving total parenteral nutrition, the metabolic alkalosis may be attributed to the loss of gastric acid from vomiting. The body compensates for this by reducing respiratory drive, which leads to an increased PaCO2.