Images Bashir Antoine Chakar (Emergency registrar) Text Genevieve Carbonatto
You get a BAT call. The ambulance are bringing in a 65 year old lady who developed acute onset chest pain radiating to her back. The paramedics tell you that she was found to be diaphoretic with a systolic BP of 130. Thinking this was an ischaemic cardiac event, she was given GTN. Her BP fell to 80/50. Just on the history you are thinking this could be an aortic dissection. Great – you have the time to organise yourself. The resuscitation room is prepared, radiology is notified, the cardiothoracic and anaesthetic teams are notified. You are responsible for the ultrasound. Effectively you are responsible for the diagnosis as she is wheeled in. You need to think ahead. What are you going to look for?
On arrival, she is cold and shut down . She is still conscious, her BP is 70/40, her HR is 80/min. She has tenderness in her epigastrium.
What is the full house for a type A dissection?
- Pericardial effusion
- Dilated aorta
- Aortic flap
- Aortic incompetence
- Possible extension into abdominal aorta – possible flap visible there
You decide to start off with a subcostal view – this will be the easiest view to see a pericardial effusion.
The clip clearly shows a pericardial effusion. You have ticked off the first of the clinical features of an aortic dissection.
You still can’t get to the chest. Too much is going on there, so you get a 4chamber view
You are disappointed. This is not a great 4CV but you have confirmed your pericardial effusion. The chest is now free. This is what you get in the parasternal long axis view (PLAX)
Again, the image quality is not great but you have more information. The aortic root is much bigger than the LA or the RV. You can just make out a possible dissection flap.
You put some colour on to look for aortic regurgitation.
Yes you have confirmed aortic regurgitation.
To improve your view, you decrease the sector width, move one rib space higher and move closer to the sternum to get a more dedicated ascending aorta view.
You have now confirmed the dissection flap.
You move down to the abdominal aorta
You see an abdominal aortic dissection flap confirming extension of the dissection to the abdominal aorta.
The exam has taken at most 3 to 4 minutes. You have confirmed a full house for the diagnosis of an aortic dissection- pericardial effusion, dilated ascending aorta, aortic dissection flap, aortic regurgitation and dissection down to the abdominal aorta.
CT is ready for the patient. Her BP is hovering around 80 systolic but she still goes to CT. CT confirms a Type A dissection with contained rupture and extension to the common iliac arteries. Theatres are ready for the patient. She undergoes aortic and hemiarch replacement and survives the procedure.
Teaching point: Be prepared when you get a BAT call if you are the insonating physician. Just like all other members of the resuscitation team , it requires mental preparation. Know what you will be looking for and how to best look for it so that the examination using ultrasound is seamless.