Final answer:
Patients with COPD should not receive oxygen via nasal cannula at flow rates exceeding 2-4 liters per minute, to prevent carbon dioxide retention and respiratory depression by maintaining oxygen saturation levels within 88-92%.
Step-by-step explanation:
A client with Chronic Obstructive Pulmonary Disease (COPD) should not receive Oxygen therapy by nasal cannula at flow rates greater than 2-4 liters per minute. The concern is that higher concentrations of oxygen can lead to suppression of the individual's drive to breathe, which is often dependent on the levels of oxygen and carbon dioxide in the blood. It is important to carefully titrate oxygen therapy in COPD patients to maintain their oxygen saturation levels at the target range, typically 88-92%, to avoid side effects such as carbon dioxide retention and respiratory depression.