A controversial study estimates the risk of venous thromboembolism, or serious blood clot, at 1% for those undergoing knee replacement and .5% for those receiving a new hip during the few days they recuperate in the hospital after surgery.
The authors, Jean-Marie Januel and colleagues from Lausanne University Hospital in Switzerland and co-authors in France and Canada, used data from 47 studies, most of them randomized controlled trials.
They suggest that because VTE is the most frequent surgical adverse event besides infections, their rates might be used for quality analysis and hospital benchmarking Additionally, they write, there is no widely accepted estimate of symptomatic VTE risk prior to hospital discharge that might be "conveyed to patients in the informed consent process."
VTEs, which can result in sudden death, are thought to be largely preventable, especially since one in four VTEs occur in patients who had major surgery such as hip and knee replacements.
All of the patients included received recommended prophylactic medications.