Final answer:
The patient's symptoms suggest a possible pulmonary embolism, a condition that arises from a blood clot reaching the lungs, causing a ventilation/perfusion mismatch. A serum D-dimer test is a usual step in assessing the presence of a clot. Medical professionals would tackle this urgently while providing a clear and empathetic explanation to the patient's partner.
Step-by-step explanation:
The symptoms described suggest the possibility of a pulmonary embolism (PE), a potentially life-threatening condition that occurs when a blood clot travels to the lungs and causes a blockage. Given the recent surgery and subsequent immobility, this patient is at increased risk for deep vein thrombosis (DVT), which can lead to PE. The shortness of breath and anxiety are common symptoms of PE, and thus, a serum D-dimer test, while not definitive, is often run as an initial screening tool to assess the presence of an abnormal or excessive blood clotting situation.
A PE can cause a ventilation/perfusion mismatch by obstructing the blood flow through the lungs, while ventilation may still be adequate. Because the blood is not able to get past the clot to participate in gas exchange, the affected portion of the lung is not able to oxygenate the blood, leading to symptoms such as shortness of breath.
To the patient's partner who is concerned about the breathing problem, a sensitive and straightforward explanation is required. One might say, "She may have developed a clot in her blood that has traveled to her lungs, which is making it hard for her to breathe properly. The medical team is working to diagnose and treat this condition as quickly as possible to help her breathe more easily."