Earlier this month we reported the publication in Resuscitation Journal of the Reason study. Thanks to Dr. Atkinson (one of the authors of this study) for providing us with this explainer.

Point-of-Care Ultrasound in Cardiac Arrest

Resuscitation Journal, Sept 2016

Absence of cardiac activity on point of care ultrasound during PEA and asystole, is associated with very poor survival rates.

Some clinicians use a lack of cardiac activity on ultrasound as a reason to terminate resuscitation efforts. We at the Saint John Regional Hospital Emergency Department (ED) participated in this prospective observational study at 20 EDs across North America. We assessed the association between cardiac activity on point of care ultrasound (PoCUS) during advanced cardiac life support (ACLS) and survival to hospital discharge in patients with pulseless electrical activity (PEA) or asystole. Patients were included if they received at least one round of ACLS resuscitation after the initial ultrasound. Patients were excluded if they presented with a shockable rhythm, had immediate return of spontaneous circulation (ROSC), or the resuscitation was terminated immediately after the initial ultrasound.

Of 793 patients with out-of-hospital cardiac arrest enrolled, 26% had ROSC, 14% survived to hospital admission, and 1.6% survived to discharge. Among 530 patients without cardiac activity on PoCUS, only 0.6% survived to discharge (compared with 3.8% of those with cardiac activity).

Cardiac activity on PoCUS and an initial rhythm of PEA on ECG were associated with ROSC (odds ratios, 3.0 and 2.8, respectively) and with survival to hospital admission (ORs, 3.6 and 2.1, respectively). Cardiac activity was associated with survival to discharge (OR, 5.7).

In patients with asystole, lack of cardiac activity had a sensitivity of 90% and predictive value of 99% for non–survival to hospital discharge (death).

PoCUS identified pericardial effusion in 34 patients and suspected pulmonary embolism in 15 who received thrombolytic therapy.

How does this affect care?

There is always an argument that the association between dismal survival and lack of cardiac activity is just a self-fulfilling prophecy, if absence of cardiac activity led to early termination of salvageable resuscitations. In this study, resuscitation had to continue until at least 2 scans were completed.

So, unless there are very special circumstances, such as significant hypothermia, or post defibrillation, it seems safe to terminate resuscitation for most patients with asystole on ECG and without cardiac activity on ultrasound.

References

Gaspari R, Weekes A, Adhikari S, Noble VE, Nomura JT, Theodoro D, Woo M, Atkinson P, Blehar D, Brown SM, Caffery T, et al. Emergency department point-of-care ultrasound in out-of-hospital and in-ED cardiac arrest. Resuscitation. 2016;109:33-9. http://dx.doi.org/10.1016/j.resuscitation.2016.09.018

Daniel M. Lindberg reviewing Gaspari R et al. Resuscitation 2016. Journal Watch. www.jwatch.org/na42452/2016/10/03/point-care-ultrasound-cardiac-arrest