[Sherlock digs through John's bag and finds the suture holder and the suture needle. They're both, thankfully, in their sealed cases.]

It shouldn't be a problem...

[He doesn't realise that John would prefer doing it himself. He looks around, holding both of those items then sets them on his lap.]

So... what's first. Disinfectant and antiseptic, correct? Let's see... where is it... [He picks up the bottle and also one of those big packages of gauze. He opens the gauze with his teeth and pulls it out, then pouts a generous amount of the antiseptic on the cloth. He sets the bottle to the side after closing it up, then he moves forward, which knocks the suture holder and suture needle onto the ground.]