Occlusive bandage

An occlusive bandage (such as a Tegaderm patch or HydroGel or even just saran wrap) is a sealed dressing that covers a wound and stops air from getting at it. Because the occlusive dressing hermetically seals the wound, it helps prevent infection, as well as keeping in moisture and body fluids.

Occlusive dressings (which are anaerobic, or air blocking) are also used when applying the topical anesthetic EMLA cream since it becomes inert after contact with air. In addition, many suspension groups cover fresh suspension wounds with occlusive dressings since unlike gauze pads they'll keep blood off of your t-shirt!