Because modern methods of deep vein thrombosis prophylaxis have low complication rates, routine prophylaxis should be considered for patients over 60 years of age or patients with other medical co-morbidities undergoing transfemoral amputation for musculoskeletal malignancy, according to recent study results published in the European Journal of Surgical Oncology.
“We had an unexpected death following a ‘routine’ transfemoral amputation — which turned out to be from a pulmonary embolus in a patient who was otherwise fit and healthy,” Robert Grimer, Royal Orthopaedic Hospital, Birmingham, UK, told O&P Business News. “So we did an audit on the risks of having an amputation.”
Transfemoral amputation risks
A search of the Royal Orthopaedic Hospital’s oncology database showed that 484 patients underwent transfemoral amputation from 1980 to 2011. Osteosarcoma was the most common diagnosis that led to amputation (45%) and chondrosarcoma was the second most common (6%). Sixty-two percent of patients underwent transfemoral amputation as a primary procedure, 26% as a secondary procedure and 12% as a third or greater number procedure. Soon after transfemoral amputation there were two inpatient deaths, followed by two more within 30 days of the procedure. However, only two deaths were directly related to the procedure, both due to pulmonary embolus, according to study results.
Overall, the rate of 1-year survival was 79% and the rate of 5 year survival was 52%. According to study results, patients who underwent amputation due to failure of reconstruction or as a secondary or greater procedure had better rates of survival. Researchers found the most common cause of death was metastatic disease. In the defined perioperative period of 30 days, the incidence of non-fatal, clinically evident thromboembolic events was 0.6%.
“The results showed that we had just two perioperative deaths within 30 days from pulmonary emboli in 484 amputations. A very low rate, but both could potentially have been prevented by deep vein thrombosis (DVT) prophylaxis,” Grimer said. “Anyone having a transfemoral amputation for a tumor related condition should be evaluated and if they have a risk factor for DVT/pulmonary embolism they should have prophylaxis.”
Future studies
Although Grimer and colleagues answered some questions about the risks for DVT/pulmonary embolism during transfemoral knee amputation, there are still other questions surrounding DVT/pulmonary embolism and other procedures. Currently, the researchers are looking at the risks of DVT/pulmonary embolism in patients undergoing endoprosthetic replacements as well as pelvis surgery for tumors.
According to Grimer, “Musculoskeletal tumor surgery often involves quite extensive dissections which do not usually respect tissue planes. As a result there is often a large ‘raw surface’ of muscle or other tissue exposed and this tends to bleed postoperatively. This dilemma is whether the risks of bleeding outweigh the risks of DVT/pulmonary embolism.
“We did the review for the transfemoral knee amputation patients as we had one such death, we are now looking at identical projects for all the other procedures we do,” he said. “One of the accepted criteria for high risk of DVT/pulmonary embolism is a diagnosis of malignancy — which virtually all our patients have — but we seem to have very low rates despite not routinely using anti-coagulation. We hope to provide clearer guidelines and evidence in the future.”
Disclosure: Grimer has no relevant financial disclosures.
