New analysis provides information about which medications best after different types of surgery

Current guidelines do not distinguish between aspirin and more potent blood thinners for protecting against blood clots in patients who undergo major orthopedic operations, leaving the decision up to individual clinicians. A new analysis published today in the Journal of Hospital Medicine provides much-needed information that summarizes existing studies about which medications are best after different types of surgery.

Every year, hundreds of thousands of Americans undergo major orthopedic surgery such as hip and knee replacements and hip fracture repairs. Patients undergoing such operations are at risk of experiencing serious, potentially fatal blood clots. Attempts to prevent blood clots with medications that thin the blood can be problematic, though, because they can worsen bleeding, which is another serious complication after surgery. Indeed, there is considerable controversy concerning the best type of blood thinner to use: aspirin or stronger blood thinners called anticoagulants. Examples of anticoagulants include heparin and warfarin (Coumadin).

Researchers compiled and compared all relevant studies that have compared these agents following hip or knee surgery. Their analysis, which included 8 randomized trials and 1408 patients, revealed that for hip or knee replacement, aspirin may be a good option because it's as effective as heparin or warfarin for preventing blood clots, but with less risk of bleeding. After hip fracture repair, though, anticoagulation therapy appears to be more beneficial.

"We expect that the number of hip and knee replacements and hip fracture repairs will continue to grow as the population ages. Major complications after these procedures-often clots or bleeding-contribute to suffering and costs," said lead author Frank Drescher, MD of the Veterans Affairs Medical Center in White River Junction, Vermont. "We hope our findings may guide physicians trying to help their patients make decisions about how to best minimize surgical risks."