Concerning the ventilatory response to hypoxia, TRUE is:
Ventilation increases greatly at high altitude in response to hypoxic stimulation of chemoreceptors. The other choices are incorrect : It is the peripheral chemoreceptors, not the central chemoreceptors that are responsible for the response. The response is increased if the pCO2 is also raised. Hypoxic stimulation is often impoant in patients with longstanding severe lung disease who have nearly normal values for the pH of the CSF and blood. Mild carbon monoxide poisoning is associated with a normal aerial pO2 , and therefore, there is no stimulation of the peripheral chemoreceptors.
It is the major stimulus to ventilation at high altitude
It is primarily brought about by the central chemoreceptors
It is reduced if the PCO2 is also raised
It rarely stimulates ventilation in patients with chronic lung disease
Respiratory System Pa 2