Clinical scenario #1: Chronic lung disease patient.
The ventilatory drive of patients with chronic lung disease is primary due to their hypoxemia, rather than CO2 levels. This is because pCO2 receptors are adaptive. Chronically elevated pCO2 makes central receptors unresponsive in COPD patients. Administration of a high O2 mixture to relieve the hypoxemia is contraindicated because this removes the hypoxic drive, leading to severe hypoventilation.
Clinical scenario #2: Drug overdose where central receptors are blocked.
The ventilatory drive of patients with chronic lung disease is primary due to their hypoxemia, rather than CO2 levels. This is because pCO2 receptors are adaptive. Chronically elevated pCO2 makes central receptors unresponsive in COPD patients. Administration of a high O2 mixture to relieve the hypoxemia is contraindicated because this removes the hypoxic drive, leading to severe hypoventilation.
Clinical scenario #2: Drug overdose where central receptors are blocked.