The arterial blood gas below indicates that the primary acid-base imbalance is:

pH - 7.25

PaCO2 - 20 mm Hg

HCO3- - 10 mEq/L

Select all that apply:

Normal range:

pH = 7.35-7.45

PaCO2 = 36-44 mmHg

HCO3- = 22-26 mEq/L

Choice A Reason:

Hyperplasia refers to an increase in the number of cells in an organ or tissue, usually resulting in an increase in the size of the organ or tissue. This process is often a response to a stimulus and can be physiological or pathological. However, hyperplasia does not involve the replacement of one cell type with another, as seen in this case.

Choice B Reason:

Dysplasia is characterized by abnormal growth and development of cells within tissues or organs. It often indicates a precancerous condition and involves changes in cell size, shape, and organization. While dysplasia can occur in the respiratory tract, it does not describe the replacement of one type of epithelial cell with another.

Choice C Reason:

This is the correct answer. Metaplasia is the process by which one type of adult cell is replaced by another type of adult cell that is not typical for that tissue. In this case, the normal columnar ciliated cells in the bronchial airway have been replaced by stratified squamous epithelial cells, a common adaptation in response to chronic irritation from smoking.

Choice D Reason:

Hypertrophy refers to an increase in the size of cells, leading to an increase in the size of the affected organ or tissue. This process does not involve a change in cell type, making it an incorrect choice for this scenario.

Choice A Reason:

Decreased ATP production is the primary cause of sodium and water accumulation in an injured cell. ATP is essential for the function of the sodium-potassium (Na±K+) pump, which maintains the ionic balance within the cell. When ATP levels drop, the Na±K+ pump fails, leading to an influx of sodium and water into the cell, causing cellular swelling.

Choice B Reason:

Calcification of the cell refers to the abnormal deposition of calcium salts within the cell. While calcification can occur in injured cells, it is not directly responsible for sodium and water accumulation. Calcification is more related to chronic injury and cell death rather than acute cellular swelling.

Choice C Reason:

Ribosome detachment from the endoplasmic reticulum can occur due to cellular stress and injury, leading to reduced protein synthesis. However, this detachment is not the direct cause of sodium and water accumulation. The primary issue is the failure of the Na±K+ pump due to decreased ATP production.

Choice D Reason:

Dehydration refers to the loss of water from the body or cells. While dehydration can affect cellular function, it is not the cause of sodium and water accumulation in injured cells. The accumulation is primarily due to the failure of the Na±K+ pump, which is dependent on ATP.