Question – How can you use ultrasound to figure out the etiology of a cardiac arrest?

Much of the buzz surrounding ultrasound in cardiac arrest revolves around the intra-arrest echo and TEE. You can also use ultrasound to get some information about the etiology of the arrest. Enter the SESAME Protocol, developed by Daniel Lichtenstein (aka the Lung King).

The SESAME Protocol is a 5-step method that can be performed in two minutes or less:

  1. Lungs – look for a PTX. Best done after a patient is intubated and being ventilated. Preferably done before several rounds of compressions have happened. Obvious note – the PTX you see may be due to a rib fracture, thus limiting its utility.
  2. Legs – Look for a DVT in the b/l fems – many patients with massive PE may have a concurrent DVT. If present, look for RV dilation. Consider code-dose thrombolytics.
  3. Abdomen – quickly scan the abdomen to look for free fluid. The goal is speed, so while you could do a full FAST, what you’re really interested in is a massive amount of free fluid that can be obviously seen. If you have this, consider hypovolemia and the need to transfuse blood product.
  4. Pericardium – evaluate for pericardial tamponade.
  5. Heart – Evaluate for RV dilation, asystole, echocardiographic evidence of fine VF. Echo windows best done after compressions are stopped.

Here’s a video of the Lichtenstein demonstrating the SESAME Protocol. I haven’t found any evidence of this protocol being rigorously investigated for effects on cardiac arrest mortality or other patient centered outcomes. Nevertheless, it’s a neat idea.


  1. Lichtenstein et al. 2016 – Critical Care Ultrasound in Cardiac Arrest
May 2024