Why do you not give oxygen to COPD patients?

As a pulmonologist with extensive experience in treating patients with respiratory conditions, I can explain the rationale behind the cautious approach to oxygen therapy in patients with Chronic Obstructive Pulmonary Disease (COPD). In patients with COPD, the normal respiratory homeostasis is disrupted. Healthy individuals respond to a rise in carbon dioxide levels by increasing their breathing rate to expel the excess gas. However, in some COPD patients, this response is diminished, and they become reliant on low oxygen levels to stimulate their breathing, a phenomenon known as hypoxic drive. Administering too much oxygen to these patients can potentially reduce their hypoxic drive, leading to a decrease in their respiratory rate and an accumulation of carbon dioxide in the body, a condition known as hypercapnia. Hypercapnia can lead to respiratory acidosis and further complications, including respiratory failure. Therefore, the goal of oxygen therapy in COPD patients is to provide just enough supplemental oxygen to relieve hypoxemia (low blood oxygen levels) without suppressing the patient's hypoxic drive. This is often achieved by using a low-flow oxygen delivery system that allows for precise control of the inspired oxygen concentration.

Respiratory homeostasis: in healthy individuals, a rise in carbon dioxide causes an increase in the drive to breathe. However, in some patients with chronic obstructive pulmonary disease, this response has been blunted, leaving low oxygen levels as the main stimulus of respiration (hypoxic drive).