It seems that 5 half-lives are recommended in loco regional anesthesia, like spinal anesthesia. 

Dabigatran is an oral direct thrombin inhibitor. Its peak plasma levels occur at 2 hours, and its half-life is 8 hours after a single dose but up to 17 hours after multiple doses. A minimum of  48-hour interval is recommended before a neuraxial injection.

However, to be on safer side 72 hours (or longer in renal dysfunction) may be optimal after multiple doses.

See the link or the attached file

-Parimal

New anticoagulants and regional anesthesia. Llau JV1, Ferrandis R. It suggests that the risks from new anticoagulants are underestimated. Hope this helps Alkisti

I would also go with 3 days. Take a look at this article:

Thank you for this article