Network Five: ECMO

Network Five: Episode 3a – ECMO

Participants: Dr Pramod Chandru, Kit Rowe, Shreyas Iyer, Caroline Tyers and, Samoda Wilegoda Mudalige.

Part 1

In this episode, we discuss the feasibility of setting up an ECMO service for refractory OOHCA, an exciting study conducted by Dr Pramod Chandru et al. at Westmead Hospital that will serve as the database for comparison with the RESET trial

• Chandru P, Mitra TP, Dhanekula ND, Dennis M, Eslick A, Kruit N, Coggins A. Out of hospital cardiac arrest in Western Sydney-an analysis of outcomes and estimation of future eCPR eligibility. BMC Emerg Med. 2022 Feb 28;22(1):31

Take-Home Points:

• This paper was a prospective observational study of consecutive out-of-hospital of cardiac arrests (OOHCAs) at Westmead Hospital over a 3-year period.
• It looked at the feasibility of setting up an ECMO service for refractory OOHCAs (i.e. for patients who have received CPR for 20 minutes or longer, between the ages of 18 and 70 years, and had a VF arrest).
• This study had 17 patients who would have qualified as true refractory OOHCAs (none of whom survived to hospital discharge).  
• This proportion of patients was similar to other studies that have been undertaken on this topic, which also demonstrated a survival to hospital discharge with good neurological recovery of around 35-40% with the use of ECMO CPR. 
• The 2CHEER study performed out of Melbourne is also a good reference for this subject – this was one of the first RCTs for the use of ECMO CPR in a pre-hospital setting (see reference below).
• Westmead Hospital will be one of the centers involved in the upcoming RESET trial looking at the implementation of ECMO CPR.  

Part 2

In this second part of the series, we discuss the potential role of aortic dissection risk score and D-dimer in diagnosing acute aortic syndromes.

• Bima P, Pivetta E, Nazerian P, Toyofuku M, Gorla R, Bossone E, Erbel R, Lupia E, Morello F. Systematic Review of Aortic Dissection Detection Risk Score Plus D-dimer for Diagnostic Rule-out Of Suspected Acute Aortic Syndromes. Acad Emerg Med. 2020 Oct;27(10):1013-1027.

Take-Home Points:

• This meta-analysis suggested a sensitivity of 97.6-99.9% for an aortic dissection risk score of 0-1 and a negative D-dimer (<0.5) or age-adjusted D-dimer in the identification of acute aortic syndromes. 
• However, this meta-analysis only included 4 studies, only one of which was prospective. 
• This may be a useful clinical tool when used in the right context, while still using our clinical gestalt (it should not be used unless you have a clinical suspicion that your patient may have an acute aortic syndrome). 
• On the other hand, the use of this tool also has the potential to increase the number of CT scans performed to investigate the presence of acute aortic syndromes (particularly if wrongly applied). 
• Lastly, remember to make sure you are only using D-dimer to work up low-risk patients. 

Part 3

In this final part of the series, we talk about the utility of double defibrillation for refractory cardiac arrest.

• Miraglia D, Miguel LA, Alonso W. Double Defibrillation for Refractory In- and Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis. J Emerg Med. 2020 Oct;59(4):521-541

Take-Home Points:

• This systematic review of RCTs looking at double defibrillation for refractory VT and VF demonstrated no significant effect on rates of return of spontaneous circulation (apart from one study, whose rates of ROSC actually favoured the control group), survival to hospital admission or survival to discharge (all with low-grade evidence). 
• This is likely to be reflective of the fact that the data on double defibrillation at this stage is insufficient (rather than demonstrating that it does not work). 
• Double defibrillation at this stage can be viewed as a rescue measure that can be attempted in refractory cases, provided it does not distract from the rest of the resuscitation effort. 
• Keep your eyes peeled for the DOSE VF study which is due to be released at the end of 2022! 

Other references

Other

• Dennis M et al. Prospective observational study of mechanical cardiopulmonary resuscitation, extracorporeal membrane oxygenation and early reperfusion for refractory cardiac arrest in Sydney: the 2CHEER study. Crit Care Resusc. 2020 Mar;22(1):26-34.
• Drennan IR, Dorian P, McLeod S, Pinto R, Scales DC, Turner L, Feldman M, Verbeek PR, Morrison LJ, Cheskes S. DOuble SEquential External Defibrillation for Refractory Ventricular Fibrillation (DOSE VF): study protocol for a randomized controlled trial. Trials. 2020 Nov 26;21(1):977.

These episodes were produced with help of HETI’s Emergency Medicine Training Network 5. Please send us an email to let us know what you thought. You can contact us at [email protected]