Self-cleaning fluid delivery device for medical applications

A gas powered spraying device that can be used for single or multi-part reactive medical polymer compositions is provided. A fluid or one or more reactive solutions are sprayed independently at a tissue surface, and the spraying of each solution of multi-component embodiments is controlled by a separate valve. Each solution is provided with a separate spray outlet, and each spray outlet is surrounded by an annular sheath of flowing gas. Gas flow is provided at two or more flow levels, including a high level flow for active spraying and a low level bypass flow to remove drips and prevent clogging, which can improve device reliability. Gas pressure can be used to drive fluid to its spray outlet, as well as to spray the fluid from the outlet to the tissue surface.