What is the purpose of an occlusive chest dressing taped on three sides?

• A. To seal the chest wound and allow air escape to prevent tension pneumothorax
• B. To apply external pressure to stop bleeding
• C. To hold a splint in place
• D. To insulate the chest from cold air

Answer: (A)

An occlusive dressing taped on three sides is designed to seal the chest wound while still allowing air to escape. By fixing the dressing on three edges and leaving one edge open, it blocks external air from entering the wound but lets any air that collects in the chest during breathing vent out. This prevents air from becoming trapped and causing a tension pneumothorax, a life-threatening condition where pressure builds up and shifts the chest organs. Sealing all four sides could trap air and worsen that danger, while not sealing at all wouldn’t protect the wound from contamination. So, the three-sided approach balances sealing the wound with venting to reduce the risk of tension pneumothorax.