Chest tube is accidentally pulled out, why occlusive dressing?

If a patient pulls a chest tube out, an occlusive dressing is over the wound to avoid air re-entry.

Stop and think about what you know about the pulmonary system. If you did NOT apply an occlusive dressing, what would happen? The lung would have more trouble functioning as part of an open system. The occlusive dressing helps close the system so the lung can still work, and it's part of trying to manage the emergency.

Here is the info I have found regarding the appropriate action when a chest tube is accidentally pulled out:

Kaplan: "If the chest tube becomes dislodged, apply pressure over the insertion site with a dressing tented on one side to allow for air escape." - The RN Course Book, 14th ED, p. 228.

ATI: "If a chest tube is accidentally removed, an occlusive dressing taped on only three sides should be immediately placed over the insertion site. This allows air to escape and reduces the risk of developing a tension pneumothorax." - RN Adult Medical Surgical Review Module, Edition 7.1, p. 58.

If you think about it, taping on three sides DOES achieve the purpose of disallowing air to ENTER the chest because if the wound starts sucking in, the suction will pull the dressing down tight on the damage, creating an airtight seal. However, if the air is moving OUT through the injury, it will push the sauce up a little and allow air to exit. The idea is to create a one-way valve, the same thing you would do if you have someone with a sucking chest wound outside the hospital.

You are exactly right. The occlusive dressing is old-school, like clamping or milking chest tubes. If a person leaks the lung pleura into the pleural space, an occlusive dressing will lead to air trapping with every breath, a potentially deadly outcome. It is recommended to use a sterile gauze dressing secured on three sides.

So, I'm studying for my boards and have a few questions: 1. What is the purpose of having two hemostats or clamps at the bedside? I've read a few conflicting things. 2. How do you actually assess for a system leak? Do you use both clamps? Read conflicting things about that. 3. If the pneumo- is healed, will tidying disappear, and if so, please explain the physiology as I've read that it's because the eyelets on the tube become occluded by an expanded lung, but I just wondered if this were the reason because having the tube on suction up against parenchyma seems like it'd cause damage. Please help. Thanks in advance to anyone taking the time to respond. Have a great day.