Progressive Care Nursing Certification (PCCN) Practice Exam

What is the typical respiratory rate change associated with respiratory failure?

1. Increased respiratory rate

2. Decreased respiratory rate

3. No change in respiratory rate

4. Normal respiratory rate

The correct answer is: Increased respiratory rate

In respiratory failure, the typical physiological response involves an increased respiratory rate. This is primarily driven by the body's attempt to compensate for inadequate gas exchange, either due to reduced oxygen levels (hypoxemia) or elevated carbon dioxide levels (hypercapnia). When the lungs are not functioning effectively, the body recognizes that it's not getting enough oxygen or is unable to expel carbon dioxide efficiently, prompting an increase in respiratory effort. This increased rate is a reflex mechanism where the respiratory center in the brain responds to the changes in blood gas levels, stimulating a faster breathing rate to enhance ventilation. Therefore, individuals experiencing respiratory failure often exhibit tachypnea, which is characterized by a respiratory rate that exceeds the normal range. In certain instances of severe respiratory compromise, however, this pattern can shift to a decreased respiratory rate as fatigue sets in or if the respiratory muscles become exhausted, but such scenarios typically indicate a more advanced state of respiratory failure.