Final answer:
The nurse should continue to monitor the client after observing fluctuation of fluid level in the water seal chamber.
Step-by-step explanation:
After the insertion of a chest tube, the nurse may note fluctuation of fluid level in the water seal chamber. This fluctuation indicates that the chest tube is functioning properly and allowing for the drainage of air or fluid from the pleural space.
The appropriate action in this situation would be to continue to monitor the client. The nurse should observe the fluctuation of the fluid level over time and ensure that it remains within the expected range.