Hi! My Husband Fell And Busted His Head Open Last

Hi! My husband fell and busted his head open last night. It is only skin deep, but looks bad. Anyhow, while looking at it this morning I noticed he had HOT heat coming out the top of his head. It is really only in the center top part, but it is fairly hot. Should I be concerned of infection? The injury is only from about 15 hours ago.