A client with severe COPD is receiving oxygen therapy at 2 liters per minute via nasal cannula. The client's oxygen saturation level drops to 88% during ambulation. What action should the nurse take first?

In this scenario, the client's oxygen saturation level dropping during ambulation indicates an inadequate oxygen supply. The first action the nurse should take is to discontinue ambulation and return the client to bed. This helps stabilize the oxygen level by reducing the oxygen demand placed on the client during physical activity. Increasing the oxygen flow rate without addressing the underlying issue of oxygen saturation dropping may not be effective. Instructing the client to rest is not enough to address the immediate need for stabilization of oxygen levels. Encouraging the client to breathe more deeply may not be sufficient to overcome the oxygen saturation drop caused by inadequate oxygen supply during ambulation.