Quote from GermPhobe
When you've got bubbling going on in a Pluerevac, WHERE exactly might the leak be? Some people have said it's at the dressing site, but this doesn't make sense to me. The open end of the tube is in the pleural space, right? If the Pleurevac is emptying blood from the pleural space, and air is entering the system, where is it coming from???
An air-leak in the system could be coming from ANYWHERE proximal to the pleurevac...If the leak is new, a thorough(sp?) assessment of the tube, connections, pleurevac, and dressing/puncture site should should be done because if it's a break in the system, it's usually something you can fix.
IN simplest of terms, the chest-tube system is a vacuum ('suction cup') that exerts enough 'sucking force' to keep the lung expanded. If a 'hole' (leak) exists anywhere (from the source of the suction (plerevac box) to the lung) along this 'vaccum', air will be 'sucked' into the 'vaccum' from the breach ('hole')...and this is where/why/when the air-leak 'bubbles' occur...
Or...pretend you're sucking down a milk-shake (straw is the chest tube, shake is the lung/pleura, your mouth is the plerevac/wall suction)...if someone then pokes a hole anywhere in your straw you'll suck air (ie a leak in the tubing or connections)...or if your straw isnt quite into the shake you'll suck air (ie a leak from puncture and/or pleural space)...in either case you're sucking air into your mouth (if a water-seal chamber were in your mouth it would bubble)
Yes you can sometimes hear air being sucked in from the puncture/incision site if a big leak is occuring there...but whether you do or not, you'll STILL get bubbles in your water-seal. (btw, this is rare and 'usually' occurs when someone pulls/bumps/displaces a relatively new tube...and makes for a bad day for all involved)...
SO...an air-leak/bubbles in the water-seal chamber only tells you that there IS an air-leak...but not WHERE it is occuring...
and..you can have air-leaks whether the tube is there to drain effusion, to re-expand pneumothorax...or draining mediastinum post open-heart...or etc...it doenst matter...air leaks can occur.