Final answer:
The priority action when facing a complication with a central venous access device is to immediately notify the healthcare provider for proper assessment and intervention.
Step-by-step explanation:
When dealing with a complication involving a central venous access device during intravenous therapy, the priority action is to notify the healthcare provider immediately. This step is crucial because the healthcare provider can assess the situation and determine the appropriate intervention, which may include the removal of the device, administration of medication, or application of pressure to the site depending on the specific complication. Prompt communication is essential to prevent further harm and to manage the complication effectively.