1. Chest Drains By Michael Shackcloth

2. Function • Conduit to remove fluid or air from the pleural or pericardial spaces • The fluid may be blood, pus or pleural effusion • Allow the lungs and heart to work unrestricted

3. Compartments of the chest

4. Spaces That Need Draining Following Heart Surgery • ANY SPACE THAT HAS BEEN OPENED IS A POTENTIAL SITE WHERE BLOOD MAY COLLECT • Valve surgery - Pericardium • Bypass graft surgery – Pericardium • Left pleural space if opened during LIMA harvest • Right pleural space if opened during RIMA harvest • Right pleural space often opened during OPCAB to allow heart to move across making grafting easier

5. Spaces That Need Draining Following Thoracic Surgery • Only a single pleural cavity opened • Air and blood may collect in the space • Two drains • Apical drain – Air • Basal drain – Blood • Traditionally apical drain is placed anteriorly and basal drain at the back

6. Physiology of Chest Drains

7. Mechanism of Action • Fluid or air passes from an area of high pressure to one of a lower pressure • An underwater seal is therefore needed to stop air being sucked into the chest via the drain

8. Mechanism of Action • Drainage occurs when pleural pressure is positive (unless suction is applied) • Fluid within the pleural cavity drains into the water seal • Air bubbles through the water seal into the outside world • Length of tubing below the fluid level is important. The longer the length the greater the resistance to drainage

9. Chest Drain

10. Suction • What does it do? • Makes the external pressure negative • Air or blood drains more easily out of chest Dangers • If on to high tissues may get sucked into the drain damaging them • If connected but not on similar effect to clamping the drains

11. Does and Don’ts of Chest Drains • Do not clamp a functioning drain as this can lead to a tamponade ortension pneumothorax • If becomes disconnected, reconnect and ask patient to cough • Always keep drain below level of patient • If raised above patient the contents may siphon back into the chest

12. Drain Removal • Explain to patient what you are going to do and what they have to do • Get everything ready • Check suture is in place to close drain hole • Get patient to practice what is expected of them.

13. Timing of Drain Removal • Remember air moves from higher pressures to lowest pressure • Pleural pressure always lower than atmospheric pressure so air will move into the pleural space from outside

14. On Expiration • Pleural pressures at their highest • But still less than atmospheric pressure • Difficult to hold breath at full expiration • Natural reaction to pain is to take a deep breath in

15. On Inspiration • Easy to hold breath on maximal inspiration • Pleural pressure most negative therefore air more likely to move into pleural space

16. Valsalva Manoeuvre • Forced expiration against a closed glottis • Creates a positive intrapleural pressure • Easy for patient to hold

17. Any Questions ?