Point-of-care cardiac ultrasound during cardiac arrest: a reliable tool for termination of resuscitation?

Purpose of review Point-of-care ultrasound (POCUS) is commonly used during cardiac arrest to screen for potential causes and to inform termination of resuscitation. However, unique biases and limitations in diagnostic and prognostic test accuracy studies lead to potential for misinterpretation. The present review highlights recent evidence regarding POCUS in cardiac arrest, guides the incorporation of POCUS into clinical management, and outlines how to improve the certainty of evidence. Recent findings Multiple frameworks organize and direct POCUS during cardiac arrest. Although many are proofs of concept, several have been prospectively evaluated. Indirect evidence from undifferentiated shock suggests that POCUS offers better specificity than sensitivity as a diagnostic aid. The prognostic accuracy of POCUS during cardiac arrest to predict subsequent clinical outcomes is better characterized, but subject to unique biases and confounding. Low certainty direct evidence suggests that POCUS offers better specificity than sensitivity as a prognostic aid. POCUS findings might indicate a particular diagnosis or encourage the continuation of resuscitation, but absence of the same is not sufficient in isolation to exclude a particular diagnosis or cease resuscitation. Until the evidence to support POCUS during cardiac arrest is more certain, it is best characterized as a diagnostic and prognostic adjunct.