Tension pneumothorax

What it is

Tension pneumothorax is air leaking into the pleural space but not coming out, through a 1-way valve. Air in the pleural space keeps increasing and is unable to escape, so the pleural cavity pressure rises above the atmospheric pressure and the collection is pushing everything to the other side. Pneumothorax itself is set out in three named types by that same pressure: closed pneumothorax, where the pleural cavity pressure is less than the atmospheric pressure; open pneumothorax, where the pleural cavity pressure is equal to the atmospheric pressure and air is leaking into the pleural space and coming out; and tension pneumothorax, where the pleural cavity pressure is greater than the atmospheric pressure. What sets tension apart at the bedside is hemodynamic: tension pneumothorax causes hemodynamic abnormalities and a simple pneumothorax does not. The mechanism is a kink of the aortic inlet with a rise in after load, together with a fall in venous return and preload from the change in pressure gradient, so the shock it produces is obstructive shock.