Conan, seriously. Worry more about the injury, less about calculations.

Dairine focuses, mentally reciting the healing spell as she holds the jacket in place. Gradually, the bleeding slows and eventually stops. One might think the pressure did it, though the results were rather fast. The spell's only indication is the heavy breathing from Dairine, as though she's just exerted herself (despite having been sitting this whole time).

"I think we're good," she whispers. So long as he doesn't aggravate the injury too badly.