Chest Drains

Under water seal drain, chest tube or pleural drains

A chest tube is a long hollow tube that is inserted between the ribs and into the pleural space, which is the space surrounding the lungs.

An underwater seal drain, also called an UWSD, a chest drain or a pleural drain, is a specialised drain that’s attached to a chest tube.

Chest tubes are normally inserted under a local anaesthetic, or under a general anaesthetic if the person is undergoing chest surgery.

The two common complications are infection and pain.

How does it work?

A chest tube is inserted into the pleural space to drain extra air or fluid (including blood). Once the chest tube is attached to the UWSD, the extra air or fluid ‘bubbles’ through the water inside the drain. This water acts as a one-way valve, so the air or fluid cannot flow back into the space around the lungs. If both fluid and air need to be drained, the person may require 2 chest tubes.

Chest drains can look different in different hospitals.

Why or what is it used for?

Chest drains are used to remove, blood, air or pus from the pleural space. This pleural space is normally empty except for a small amount of fluid. Air or fluid may build up in the space for a number of reasons, such as during chest surgery or as a result of chest trauma or pneumonia.

The fluid or air can build up rapidly or slowly over a number of days. This air or fluid may make breathing difficult.

How long will it be used for?

Chest drains normally remain in as long as the air or fluid remains in the pleural space. The person will need to have regular chest X-rays to monitor until the problem resolves.

Important information for patients and relatives

The chest drain should be kept below the level of the chest all the time.

Pleural drains in adults: a consensus guideline consumer information

Publication details

Chest drains, version 1. Helena Sanderson, NE, Tamworth Base Hospital, April 2016.


The information on this page is general in nature and cannot reflect individual patient variation. It reflects Australian intensive care practice, which may differ from that in other countries. It is intended as a supplement to the more specific information provided by the doctors and nurses caring for your loved one. ICNSW attests to the accuracy of the information contained here but takes no responsibility for how it may apply to an individual patient. Please refer to the full disclaimer.