Summary
Patients on vitamin K antagonists (VKA) often undergo invasive dental procedures.
International guidelines consider all dental procedures as low-risk procedures, while
bleeding risk may differ between standard low-risk (e. g. extraction 1–3 elements)
and extensive high-risk (e.g. extraction of >3 elements) procedures. Therefore current
guidelines may need refinement. In this cohort study, we identified predictors of
oral cavity bleeding (OCB) and evaluated clinical outcome after low-risk and highrisk
dental procedures in patients on VKA. Perioperative management strategy, procedure
risk, and 30-day outcomes were assessed for each procedure. We identified 1845 patients
undergoing 2004 low-risk and 325 high-risk procedures between 2013 and 2015. OCB occurred
after 67/2004 (3.3 %) low-risk and 21/325 (6.5 %) high-risk procedures (p=0.006).
In low-risk procedures, VKA continuation with tranexamic acid mouthwash was associated
with a lower OCB risk compared to continuation without mouthwash [OR=0.41, 95 %CI
0.23–0.73] or interruption with bridging [OR=0.49, 95 %CI 0.24–1.00], and a similar
risk as interruption without bridging [OR=1.44, 95 %CI 0.62–3.64]. In high-risk procedures,
VKA continuation was associated with an increased OCB risk compared to interruption
[OR=3.08, 95 %CI 1.05–9.04]. Multivariate analyses revealed bridging, antiplatelet
therapy, and a supratherapeutic or unobjectified INR before the procedure as strongest
predictors of OCB. Non-oral cavity bleeding (NOCB) and thromboembolic event (TE) rates
were 2.1 % and 0.2 %. Bridging therapy was associated with a two-fold increased risk
of NOCB [OR=1.93, 95 %CI 1.03–3.60], but not with lower TE rates. In conclusion, predictors
of OCB were mostly related to perioperative management and differed between low-risk
and high-risk procedures. Perioperative management should be differentiated accordingly.
Keywords
Clinical studies - vitamin K antagonist - surgery - risk factors