Scott saw a patient overnight who presented with severe chest and back pain and L arm weakness. She was hypotensive and bradycardic; in cardiogenic shock.
Classic for a dissection.
Scott had a look with the ultrasound:
Subxiphoid view showing a pericardial effusion and the aorta with a dissection flap in the lumen (annotated below).
Abdominal Aorta (trans) showing a dissection flap in the lumen of the aorta (annotated below).
Cardiothoracics met the patient in CT and they were taken to theatre from CT. 40 minutes from presentation to theatre. Not Bad!
I know from the story the patient had an obvious dissection.
I think what US does (as it does in most ED situations) is that it allows us to be sure of the diagnosis; rather than the diagnosis being the highest one in a differential: thereby allowing activation of the appropriate unit and theatre with confidence.
US is best in these situations as a rule in test. Remember that TTE is not sensitive enough to rule out dissection.
But seeing a dilated aortic root, a dissection flap or significant aortic regurgitation has sensitivities in the 70-80s for aortic dissection with specificities in the 90s (1,2,3). So if you see pathology you can be confident you've made the diagnosis.
Keep scanning everyone.
1.Fojtik, JP, Costantino, TG, and Dean AJ THE DIAGNOSIS OF AORTIC DISSECTION BY EMERGENCY MEDICINE ULTRASOUND. The Journal of Emergency Medicine, Vol. 32, No. 2, pp. 191–196, 2007.
2. Victor MF, Mintz GS, Kolter MN, Wilson AR, Segal BL. Two- dimensional echocardiographic diagnosis of aortic dissection. Am J Cardiol 1981;48:1155–9
3.Sullivan PR, Wolfson AB, Leckey RD, Burke JL. Diagnosis of acute thoracic aortic dissection in the emergency department. Am J Emerg Med 2000;18:46–50.