A patient who is 18 hours post right BKA reports sudden chest pain and low pulse ox. What condition might they be experiencing?

The situation described indicates that the patient is experiencing symptoms that are highly suggestive of a pulmonary embolism. A pulmonary embolism occurs when a blood clot dislodges from a vein (often from the legs, particularly after a surgical procedure like a below-knee amputation) and travels to the lungs, where it can obstruct blood flow.

The sudden onset of chest pain, especially after surgery, coupled with low oxygen saturation (low pulse ox), points strongly to this condition. The risk of developing a pulmonary embolism increases significantly post-operatively due to possible immobility and venous stasis.

While myocardial infarction, sepsis, and pneumonia could potentially cause chest pain and low oxygen levels, the combination of a recent surgery (right BKA), the acute nature of the symptoms, and the patient's risk factors align most closely with pulmonary embolism. For instance, myocardial infarction typically presents with pain that is more substernal and not specifically associated with recent surgery or activity level. Sepsis usually involves systemic signs of infection, which are not mentioned in this scenario. Pneumonia could lead to similar symptoms but would typically present with additional respiratory findings or fever, which are not specified here. Thus, the acute nature of the symptoms in the