Clinical Brief – August 15th
Blood thinners and surgeries don’t mix. For those on certain blood thinners, stopping treatment for 3 days before a surgery may give the body enough time to detox.
Where’s the evidence?
Researchers from France and Belgium did a prospective observational study involving about 420 patients taking a class of blood thinners called DOACs. Specifically, dabigatran (Pradaxa), rivaroxaban (Xarelto), and apixaban (Eliquis). A good 95% of patients were on blood thinners for A-fib.
Everyone was scheduled to go into surgery and had stopped their blood thinners at varying times before their operations. The researchers took blood samples before their surgeries and measured their drug levels. A drug concentration under 30 ng/mL was thought to be low enough to control the risk of bleeding for high-risk surgeries.
So how long should people stop treatment before their surgeries?
“54 hours was the best duration of DOAC discontinuation to predict a DOAC concentration ≤30 ng/mL”
– Godier A, et al.
In translation: Stopping treatment 54 hours before a surgery was likely to be long enough for enough drug to be cleared from the body. But since this was an awkward timing, the authors proposed 72 hours instead.
Also of note, dabigatran (Pradaxa) levels tapered off slower for patients who had lower kidney function than patients with good kidney function. This was more or less expected, but it’s still good to see confirmation.
For patients with lower kidney function and taking dabigatran (Pradaxa), it might be prudent to stop their blood thinners 4-5 days before their operation to give the drug more time to clear out of the body.
Patients on blood thinners often go off of treatment just before they have surgeries. Stop too early, and the risk of a blood clot before surgery goes up. Stop too late, and the surgery may induce an uncontrolled bleed.
This study suggests that stopping treatment 3 days in advance might be enough for some patients. It also confirmed that patients with low kidney function taking dabigatran (Pradaxa) may want to consider stopping treatment earlier before surgeries.
Last thing to remember. When blood thinners are stopped, it may be good to brush up on some of the signs and symptoms of clots help monitor any unexpected issues.