Consuturi nil visum sanguinis just doesn't seem to cohere. It looks as if the blood was about to close the wound (consuturi agreeing with sanguinis). Perhaps you intended it to be nominative plural, but then it's ungrammatical, because what verb would it be the subject of?
The only both grammatically and logically correct way I can think of to use a future participle (while otherwise keeping the same phrasing that you used) is either consuturo nil visum sanguinis (literally "to (the one/me) about to sew (the wound) together, there appeared (to be) no blood") or consuturis nil visum sanguinis (literally "to (the ones/us) about to sew (the wound) together, there appeared (to be) no blood"). The latter could translate into more idiomatic English as "Just before we closed, there appeared to be no bleeding".