EMERGENCY ULTRASOUND SECTION
An Argument for Ultrasound in Cardiac Arrest Melissa Myers, MD FAAEM and Kristine Jeffers, MD FAAEM
W
e all agree that a patientin cardiac arrest deserves the best possible treatment. If only we could all agree on what that treatment is. The role of ultrasound in cardiac arrest is controversial, with proponents citing the increased diagnostic accuracy and opponents the potential increase in pulse check time and thus a decrease in CPR effectiveness. We believe that point-of-care ultrasound (POCUS) should play a role in cardiac arrest, and thus disagree strongly with the recent International Liaison Committee on Resuscitation (ILCOR) recommendations against the routine use of ultrasound during cardiac arrest.1
The authors cite the valid concern of pulse check prolongation with the use of POCUS as a reason to avoid its use entirely. While initial studies did show increased pulse length with the use of POCUS, follow on research shown that with correct use POCUS can be used without prolonged interruption of CPR.2,3 With intentioned practice and planned evaluation it is possible to perform a full assessment without prolonging pulse checks. The ILCOR recommendations are based on a systematic review which identified 12 studies of sufficient quality to be included a qualitative synthesis and none which they could include in a meta-analysis. The authors base their recommendations off these studies, which are extremely heterogenous and often not applicable in the ED. For example, one is a validation trial for a novel POCUS algorithm in cardiac arrest, an interesting paper which describes both potential harms and diagnostic benefits from ultrasound and does not attempt to make any definitive claims regarding the use of ultrasound in cardiac arrest.4 In addition, the exclusion criteria used excluded important
research in the field, including the landmark, multi-center REASON trial evaluating the use of ultrasound in cardiac arrest.5 The authors note in their discussion that POCUS does not have a high negative predictive value in cardiac arrest. They are correct but misunderstand the use of POCUS in this situation. Experts in POCUS agree that POCUS in cardiac arrest is often not
the full understanding of the limitations and the need to avoid increased pulse check time.7,8 The ILCOR recommendation against the routine use of ultrasound during cardiac arrest comes with a risk of missing intervenable causes of cardiac arrest with the potential to cause patient harm. When done by properly
The ILCOR recommendation against the routine use of ultrasound during cardiac arrest comes with a risk of missing intervenable causes of cardiac arrest with the potential to cause patient harm. a “rule out” exam, rather its utility is in finding evidence to support a potential diagnosis. The utility of ultrasound in cardiac arrest is primarily to find a small group of patients which require interventions outside the usual algorithm. In the REASON trial, 34 patients out of a cohort of 793 patients were found to have a pericardial effusion, with 13 requiring a pericardiocentesis. This group, although small, had a significantly higher survival to hospital discharge than the rest of the cohort. In addition, the REASON trial demonstrate the utility of ultrasound in predicting outcomes in patients with cardiac standstill and avoiding futile resuscitation attempts.5 Ultrasound can be used to evaluate for right heart strain, which in the right clinical situation can direct early administration of thrombolytics.6 Experts in this field will argue for the use of ultrasound in cardiac arrest, with
trained physicians with pre-prepared protocols POCUS in cardiac arrest can improve patient outcomes through the early diagnosis of reversible pathology and the avoidance of futile resuscitative outcomes. References 1. Reynolds JC NT, O’Neil BJ, Drennan I, Issa M, Welsford M. Diagnostic Test Accuracy with Point-of-Care Ultrasound During Cardiopulmonary Resuscitation to Indicate the Etiology of Cardiac Arrest: Consensus on Science with Treatment Recommendations. Accessed January 28, 2023. 2. Gaspari R, Harvey J, DiCroce C, et al. Echocardiographic pre-pause imaging and identifying the acoustic window during CPR reduces CPR pause time during ACLS–A prospective Cohort Study. Resuscitation Plus. 2021;6:100094. Countinued on page 48 >>
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