Transoesophageal echocardiography in cardiac arrest: From the emergency department to the intensive care unit

Cardiac arrest is a hyper-acute condition with a high mortality that requires rapid diagnostics and treatment. As such, point-of-care ultrasound (POCUS) has become a valuable tool in the assessment of these patients. While transthoracic echocardiography (TTE) is the more conventional modality used to find reversible causes of cardiac arrest, transoesophageal echocardiography (TOE) has been increasingly utilised due to its superior image quality, continuous imaging, and ability to be operated away from the patient's chest. TOE also has a number of applications in the aftermath of cardiac arrest, such as during the initiation of extracorporeal cardiopulmonary resuscitation (ECPR) and the subsequent monitoring of extracorporeal membranous oxygenation (ECMO). As TOE has evolved, multiple variations have been developed with different utilities. In this article, we will review the evidence supporting the use of TOE in cardiac arrest and where the different forms of TOE can be applied to evaluate the cardiac arrest patient in a timely and accurate manner.