- Chest drain is a conduit to remove air or fluid from the pleural cavity
- The fluid can be blood, pus or a pleural effusion
- Allows re-expansion of the underlying lung
- Must prevent entry of air or drained fluid back into the chest
- A chest drain must therefore have three components
- An unobstructed chest drain
- A collecting container below chest level
- A one-way mechanism such as water seal or Heimlich valve
Mechanism of action
- Drainage occurs during expiration when pleural pressure is positive
- Fluid within pleural cavity drains into water seal
- Air bubbles through water seal to outside world
- The length of drain below fluid level is important
- If greater than 2-3 cms increases resistance to air drainage
Insertion
- Unless emergency situation then pre-procedure chest x-ray should be performed
- Drain usually inserted under local anaesthesia using aseptic technique
- Inserted in 5th intercostal space in mid-axillary line
- Inserted over upper border of rib to avoid intercostal vessels and nerves
- Blunt dissection and insertion of finger should ensure that pleural cavity is entered
- Used to be taught that:
- To drain fluid it should be inserted to base of pleural cavity
- To drain air it should be inserted towards apex of lung
- Probably does not matter provided there is no loculation of fluid within pleural cavity
- A large drain (28 Fr or above) should be used to drain blood or pus
- Drain should be anchored and purse-string or Z-stitch inserted in anticipation of removal
Does and don'ts of chest drains
- Avoid clamping of drain as it can result in a tension pneumothorax
- Drain should only be clamped when changing the bottle
- Always keep drain below the level of the patient
- If lifted above chest level contents of drain can siphon back into chest
- If disconnection occurs reconnect and ask patient to cough
- If persistent air leak consider low pressure suction
- Observe for post-expansion pulmonary oedema
Removal
- Remove drain as soon as it has served it purpose
- For a simple pneumothorax it can often be removed within 24 hours
- To remove drain ask patient to perform a Valsalva manoeuvre
- Remove drain at the height of expiration
- Tie to pre-inserted purse-string or Z-stitch
- Perform a post-procedure chest x-ray to exclude a pneumothorax
Bibliography
Parry G W, Morgan W E, Salama F D. Management of haemothorax.
Ann R Coll Surg Eng 1996; 78: 325-326.
Tomlinson M A, Treasure T. Insertion of a chest drain. How to do it. Br J Hosp Med 1997; 58: 248-252. |