Florida State Paramedic Practice Exam

What is a common physiological response to increased PACO2 levels?

1. Decreased respiratory rate

2. Increased respiratory rate

3. Improved blood oxygen levels

4. Decreased heart rate

The correct answer is: Increased respiratory rate

An increased level of PACO2, or the partial pressure of carbon dioxide in the alveoli, is a critical stimulus for the respiratory center in the brain. When PACO2 levels rise, it typically indicates that the body is experiencing inadequate ventilation and is retaining carbon dioxide. The primary physiological response to this condition is an increase in respiratory rate, aimed at expelling the excess carbon dioxide and restoring normal gas exchange. By increasing the respiratory rate, the body attempts to enhance the elimination of CO2 from the lungs, thereby lowering PACO2 levels back to a more manageable range. This response is part of the body's homeostatic mechanisms to maintain proper acid-base balance and ensure that oxygenation levels remain adequate. Understanding this relationship is vital for healthcare professionals, as it underscores the body's dependency on effective respiratory function to regulate carbon dioxide and maintain overall respiratory health.