Final answer:
Giving high flow rates of O2 by nasal cannulae can cause hyperoxia, impair respiratory drive leading to hypercapnia, and disrupt the partial pressure balance necessary for oxygen diffusion. High-flow oxygen is used for carbon monoxide poisoning, as it can displace carbon monoxide from hemoglobin.
Step-by-step explanation:
The administration of high flow rates of O2 by nasal cannulae can lead to several problems. If the flow rates exceed a patient's demand, it can cause hyperoxia (excess oxygen in the body's tissues), potentially resulting in oxygen toxicity which can damage the lungs and other organs. Over-oxygenation can also impair the body's respiratory drive, especially in patients with chronic obstructive pulmonary disease (COPD), where the stimulus to breathe is driven more by low oxygen levels than by high carbon dioxide levels. High levels of supplemental oxygen can diminish this drive and lead to an unsafe rise in carbon dioxide levels, a condition known as hypercapnia. Additionally, the partial pressure of oxygen is crucial for the efficient diffusion of oxygen across the respiratory membrane. When alveolar ventilation is too high or too low, it affects the partial pressure balance and thus, the oxygen distribution. When treating carbon monoxide poisoning, 100% oxygen is administered because it helps quickly displace carbon monoxide from hemoglobin, allowing it to bind with oxygen instead. Giving carbon dioxide would not work as it would not compete with carbon monoxide for binding sites on hemoglobin and would not alleviate the poisoning.