We're discussing tummy tuck drains.
After a tummy tuck or an abdominoplasty, there's often a large amount of fluid that collects between the muscle wall of the abdomen, or stomach, and the skin wall. In order to get rid of that fluid that collects, we insert small drains that go... usually there are two drains: one goes low in the abdomen and one goes high in the abdomen above the belly button. Fluid is collected through the small holes in the drain and travels through the tube into a bulb that looks like this and collects in this bulb. This bulb is emptied every time it's filled up, several times a day, and there are numbers on the side of the bulb which are used in order to record how much fluid is coming out of the surgical site.
This number is then relayed to your surgeon and, based on the amount of fluid that comes out in a 24-hour period, the surgeon determines whether or not the drains are ready to come out. If the drains come out too early then there's the possibility of a fluid collection accumulating and having no way to get out. So therefore, drains are important. Most plastic surgeons use drains, although there are some techniques that allow for surgery without drains. In general, drains are used usually for about one week and they're removed once very little fluid is coming out.