What is causing the hemodynamic changes during the right TKR in the patient with PMH?

In the context of a right total knee replacement (TKR), hemodynamic changes can occur due to various factors associated with the surgical procedure and the patient's pre-existing medical history (PMH). When considering the impact of a pulmonary embolism, this condition can significantly affect hemodynamics by obstructing blood flow in the pulmonary arteries.

A pulmonary embolism leads to increased pressure in the right side of the heart, reduces cardiac output, and can cause a decrease in oxygen saturation levels. These changes can manifest as hypotension, tachycardia, and other signs of compromised cardiovascular stability. During or after a TKR, patients are at risk for developing a deep vein thrombosis (DVT), which can progress to a pulmonary embolism, especially if there are risk factors present in their medical history, such as immobility, obesity, or prior venous thromboembolism.

The presence of a pulmonary embolism as the cause of hemodynamic changes aligns with the surgical context and the common complications seen in orthopedic surgeries. Understanding these mechanisms helps in recognizing the importance of preventative measures and early detection in the perioperative setting.