There are two types of drain.

Passive drains, commonly made of soft rubber, channel fluid to the outside of the body. The surgeon often shortens the drain over several days.

Active drains are connected to a suction. In the hospital this is usually a vacuum on the wall. Outside the hospital the drain is connected to a small palm sized device that is emptied at regular intervals. When it is emptied, compression using a vacuum is re-established so that continuous pressure is placed on the drain.

How long a drain is left in place, depends on the individual needs. It can range from a day to several weeks.

The benefit of a drain is that it helps to avoid a collection of blood (hematoma) or fluid (seroma). It also will pull the skin against the underling tissue and promote closure of a space.

Like so many other things in medicine a drain is not without risk. The major risk is that in the same way fluid can get out, infection can get in.

If you have a drain as an outpatient, you or a family member will need to look after the drain. This consists of recording the volume of fluid removed, maintaining the vacuum and avoiding infection.