The client is experiencing symptoms of a pulmonary embolism. The best action by the nurse is to place the client in a semi-Fowler’s position to enable a clear airway. Obtaining vital signs would be action number 2, to compare to established baseline data. Administering oxygen as ordered would be the third response to provide adequate oxygenation of the client. Last, prepare the client for diagnostic tests such as blood gases, ventilation-perfusion lung scan, and pulmonary angiography.