CRITICAL CARE ECHO ROUNDS: Echo in cardiac arrest

The use of critical care echocardiography in peri-arrest and cardiac arrest scenarios: Pros, cons and what the future holds

Echocardiography is being increasingly deployed as a diagnostic and monitoring tool in the critically ill. This rise in popularity has led to its recommendation as a core competence in intensive care, with several training routes available. In the peri-arrest and cardiac arrest population, point of care focused echocardiography has the potential to transform patient care and improve outcomes. Be it via diagnosis of shock aetiology and reversibility or assessing response to treatment and prognostication. This narrative review discusses current and future applications of echocardiography in this patient group and provides a structure with which one can approach such patients.

The Value of Focused Echocardiography During Cardiac Arrest

Cardiac arrest is the absence of a centrally palpable pulse and no respiratory effort in an unresponsive patient. This often-lethal medical condition affects hundreds of thousands of people in the United States alone every year. Immediate intervention is crucial to provide the patient with any chance of survival. Advanced cardiac life support (ACLS) is the cornerstone therapy for cardiac arrest. Increased awareness and proper identification of life-threatening arrhythmias is critical, as it may lead to prompt medical treatment and improved mortality. The use of focused echocardiography, during a cardiac arrest, has been a developing area of interest over the past several years. The specific aim of this literature review was to emphasize the role of a focused echocardiogram and the valuable information that can be provided during a cardiac arrest.

Échographie et prise en charge de l’arrêt cardiaque

L’arrêt cardiorespiratoire (ACR) est une situation fréquente pour les structures d’urgences et de réanimation, et l’utilisation de l’échographie y est recommandée par les sociétés savantes. Elle doit impérativement se faire sans augmentation des temps d’interruption du massage cardiaque externe. Après formation, elle permet de détecter rapidement et facilement la présence d’une contractilité myocardique qui est un élément pronostique important pouvant aider dans la décision d’arrêter la RCP. Le recours à des protocoles bien établis avec des équipes entraînées permet d’éviter une interruption prolongée de la RCP. Cependant, aucune étude humaine de grande ampleur n’a permis de décrire de manière fiable pendant l’ACR la sémiologie échographique des causes curables que constituent l’hypovolémie, l’embolie pulmonaire, la tamponnade et le pneumothorax compressif.

Echocardiography in cardiac arrest: An emergency medicine review

INTRODUCTION

Cardiac arrest management primarily focuses on optimal chest compressions and early defibrillation for shockable cardiac rhythms. Non-shockable rhythms such as pulseless electrical activity (PEA) and asystole present challenges in management. Point-of-care ultrasound (POCUS) in cardiac arrest is promising.

OBJECTIVES

This review provides a focused assessment of POCUS in cardiac arrest, with an overview of transthoracic (TTE) and transesophageal echocardiogram (TEE), uses in arrest, and literature support.

DISCUSSION

Cardiac arrest can be distinguished between shockable and non-shockable rhythms, with management varying based on the rhythm. POCUS provides a diagnostic and prognostic tool in the emergency department (ED), which may improve accuracy in clinical decision-making. Several protocols incorporate POCUS based on different cardiac views. TTE includes parasternal long axis, parasternal short axis, apical 4-chamber, and subxiphoid views, which may be used in cardiac arrest for diagnosis of underlying cause and potential prognostication. TEE is conducted by inserting the probe into the esophagus of intubated patients, with several studies evaluating its use in cardiac arrest. It is associated with few adverse effects, while allowing continued compressions (and evaluation of those compressions) and not interrupting resuscitation efforts.

CONCLUSIONS

POCUS is a valuable diagnostic and prognostic tool in cardiac arrest, with recent literature supporting its diagnostic ability. TTE can guide resuscitation efforts dependent on the rhythm, though TTE should not interrupt other resuscitation measures. TEE can be useful during arrest, but further studies based in the ED are needed.