1. Anaesthetic Emergencies Air Embolism Dr T E Allan Palmer FRCA FANZCA MD allan@palmer.net.au allan@palmer.net.au

2. Aetiology - Passive  Open venous sinuses –Neurosurgical cases in sitting position –Spinal surgery eg laminectomy –Central venous catheters

3. Aetiology - Active  Rapid blood transfusion under pressure  Laparoscopy (carbon dioxide)  Femoral canal reaming and cement  Gas cooled lasers

4. Presentation  Sudden fall in end tidal carbon dioxide  Low cardiac output  Hypoxia  bradycardia

5. Diagnosis  Capnography  Doppler  Oesophageal stethoscope –Mill Wheel murmur  Fall in oxygen saturation

7. Prevention  Care with fluid infusors –Remove all air from infusion bags –Level one type infusors  Air filter  Air detector  Care with positioning –Maintain site of surgery below level of heart where possible

8. Prevention  Care with central venous lines –Closed systems eg pressure transducers –Minimum number of connections  Change connections below heart level –Remove lines with patient head down in expiration  If blood doesn’t come out air will go in!

9. Treatment  100% oxygen  Stop doing whatever caused it –Surgeon, equipment, position  Flood air entry point with saline  Remove air if CVC in situ  Be ready with CPR to break up airlock.

10. Questions  Air embolism has no symptoms in the awake patient?  Air is rapidly absorbed from the circulation?  Air embolism can cause a stroke (CVA) ?