Question

Which of the following is the most important determinant of ventilatory rate?

A) Arterial PO2

B) Venous PCO2

C) Venous PO2

D) Arterial PCO2

Answer 1

Arterial PCO2 is the most significant driver of ventilatory rate as it affects blood pH levels. Peripheral chemoreceptors increase respiration in response to high CO2 or low oxygen levels.

Step-by-step explanation:

The most important determinant of ventilatory rate is D) Arterial PCO2. The partial pressure of carbon dioxide in arterial blood is a primary stimulus for respiratory rate adjustments. Although oxygen levels also influence ventilation, the body primarily responds to carbon dioxide levels because CO2 has a more significant effect on the acid-base balance of the blood. Peripheral chemoreceptors in the aortic arch and carotid arteries respond to high levels of CO2 or low levels of oxygen by increasing the respiratory rate to expel more CO2 and increase oxygen intake.