Seeing the heart of the problem: transesophageal echocardiography in cardiac arrest: a practical review

In-hospital and out-of-hospital cardiac arrest (CA) is common and associated with poor outcomes despite standardized protocols for advanced cardiac life support (ACLS). Echocardiography is an attractive adjunct to standard ACLS as it has the potential to rapidly diagnose the cause of CA, affect management, facilitate interventions, and guide prognoses. However, difficulty in obtaining adequate acoustic windows for transthoracic echocardiography (TTE) in a timely manner and the associated prolongation of compression pauses have led to an equivocal recommendation on the use of TTE from varying oversight committees and expert reviews. For patients with hemodynamic instability, the American College of Cardiology and other societal guideline committees recommend echocardiography as a first line of assessment, particularly if a cardiac origin is suspected. Critically ill patients often have limited transthoracic windows; and using transesophageal echocardiography (TEE) in this setting has a higher diagnostic yield. As such, TEE is recommended by the American Society of Echocardiography (ASE) in critically ill patients with limited transthoracic views. Not surprisingly, the use in critically ill patients is increasing in the intensive care unit, operating room, emergency department, and even prehospital settings. “Rescue TEE” (TEE performed to rapidly assess for the cause of hemodynamic instability, sometimes also known as “resuscitative TEE”) is particularly useful in the setting of CA. In the intra-arrest and periarrest setting, TEE has the ability to rapidly inform and guide management decisions while avoiding the limitations and interruptions in care that may occur with TTE. The following is a review of the practical application of TEE in CA, including: the benefits, potential harms, a guideline for evaluation, credentialing, and implementation barriers. The utility and benefits of TEE in CA can be divided into intra-arrest and postarrest categories (Table 1). Benefit of TEE during CA resuscitation