Paper: Bartos JA et al. The Minnesota Mobile Extracorporeal Cardiopulmonary Resuscitation Consortium for Treatment of Out-of-Hospital Refractor Ventricular Fibrillation: Program Description, Performance and Outcomes. Lancet 2020 [Link is HERE]
Clinical Question: Can a community ECMO program improve survival with good neurological outcome in patients with refractory VF/VT OHCA?
What They Did:
- Observational cohort study of consecutive patients prospectively enrolled in the Minnesota Mobile Resuscitation Consortium’s ECMO-facilitated resuscitation program
- Program components:
- 24/7 Mobile ECMO cannulation teams
- 4 dedicated ECMO cannulation team rapid response vehicles
- 3 community ECMO initiation hospitals with ED ECMO cannulation sites
- 24/7 cardiac catheterization laboratories
- Single, centralized ECMO ICU
Image from Main Article [Link is HERE]
- Patients meeting ≥2 resuscitation discontinuation criteria were declared dead:
- etCO2 ≤10mmHg
- PaO2 ≤50mmHg or O2 saturation ≤85%
- Lactic acid ≥18mmol/L
MMRC Program Performance Metrics and Benchmarks
Outcomes:
- Primary: Survival with good neurological outcome (CPC 1 or 2)
- Secondary:
- 3 month functionally favorable survival
- ECMO cannulation rate
- Safety
Inclusion:
- Adults aged 18 to 75 years
- VF/VT OHCA
- No ROSC following 3 shocks
- Automated cardiopulmonary resuscitation with a LUCAS device
- Estimated transfer time of <30min
Exclusion:
- Nursing home residents
- Known DNR orders
- Significant bleeding
- Known terminal illness
- <1-year life expectancy
Results:
- 151 patients with VF/VT OHCA
- 97/151 (64%) were refractory VF/VT OHCA
- 60 refractory VF/VT OHCA + 3 primary PEA patients out of 97 were included in the analysis
- 58 (97%) met criteria and were treated by the mobile ECMO service
- 13/58 (22%) had ≥2 resuscitation discontinuation criteria on arrival and were pronounced dead
- 45/58 (78%) received full resuscitation efforts (ECMO cannulation and CCL angiography/PCI)
- Mean age = 57 +/- 1.8 years
- EMS Agency
- Accuracy of EMS agency patient selection was 58/63 (92%)
- Despite a benchmark of <15min, paramedics were on-scene at a mean of 22.0 +/- 8.9min prior to transport (>15min in 66% of cases)
- Mean time from 911 call to patient arrival at 3 ECMO Initiation Hospitals was 46.9 +/- 12.3min
- Mobile ECMO Cannulation Team
- Mean response time was 14.9 +/- 5.7min (71% of cases had response times <15min)
- Mean time from ECMO-eligible patient arrival to ECMO initiation was 14.4 +/- 6.1min (63% received ECMO in <15min)
- All ECMO cannulations were successful without complications (45/45 patients)
- CCL
- Patients taken to CCL within 2h of 911 call in 21/45 (47%) of cases with a mean time of 121 +/- 56min
- Coronary angiography was performed in 45/58 (78%) of patients
- 29/45 (64%) had severe CAD
- 22/29 (85%) received PCI
- Timing of ECMO-Facilitated Resuscitation Cases (Of the 58 patients…)
- 27/58 (47%) had survival to hospital discharge
- 25/58 (43%) were both discharged from the hospital and alive at 3 months with CPC 1 or 2
- Of the patients discharged from the hospital, 100% were alive at 3 months with CPC 1 or 2 (25/58, 43%; 95% CI 31 to 56%)
- Mean CPC score was 1.6 +/- 0.7 and 1.3 +/- 0.7 at hospital discharge and at 3 months
Strengths:
- 1st community-wide ECMO-facilitated resuscitation program in the US
- Adhered to the STROBE guidelines for observational studies
- Funding source (Helmsely Charitable Trust) had no role in study design, collection, analysis of data, interpretation of data, or the writing/editing of the manuscript
- This cohort of patients was identified and studied separately than the group in the ARREST trial, conducted within the same system [3]
Limitations:
- Each healthcare system will have unique aspects that will require modification of this program in order to be successful
- Small patient cohort size makes it impossible to show meaningful subgroup comparisons
- Early evaluation may not reflect longer term issues include skill maintenance of the teams
- A cost analysis of having a program like this was not discussed
Discussion:
- All patients received therapeutic hypothermia (goal temp of 34C)
- Important to point out that each component of care is crucial and significantly contributes to survival.It is not just ECMO that makes the difference
- Selection of a modest number of well-trained mobile ECMO cannulation team members assures high quality performance, high patient volume, and sill maintenance
- A lack of community experience necessitated rigorous education/training programs in addition to the capability to monitor performance required
- Authors Comments on Benchmarks and Goals:
- Mean duration of CPR only decreased by 5 to 8 min compared to prior cohort studies
- Paramedic scene time longer than 15 min
- Time from arrest to coronary angiography was longer than benchmarked
- Reducing CPR time and time to CCL remains a priority in these patients to ensure survival with good neurological outcomes
Author Conclusion: “This first, community-wide ECMO-facilitated resuscitation program in the US demonstrated 100% successful cannulation, 43% functionally favorable survival rates at hospital discharge and 3 months, as well as safety. The program provides a potential model of this approach for other communities.”
Clinical Take Home Point: These authors should be commended for demonstrating what an ECMO-facilitated resuscitation program can look like when rolled out into a metropolitan community. The description of systems issues may help facilitate discussions in other communities. They demonstrated safety, and most importantly the ability to achieve functionally favorable survival rates (i.e. 43%) at hospital discharge and 3 months, in patients with refractory VF/VT arrest, a traditionally difficult population to treat.
References:
- Bartos JA et al. The Minnesota Mobile Extracorporeal Cardiopulmonary Resuscitation Consortium for Treatment of Out-of-Hospital Refractor Ventricular Fibrillation: Program Description, Performance and Outcomes. Lancet 2020 [Link is HERE]
- Zive DM et al. Survival and Variability Over Time from Out of Hospital Cardiac Arrest Across Large Geographically Diverse Communities Participating in the Resuscitation Outcomes Consortium. Resuscitation 2018. PMID: 30053457
- Yannopoulos D et al. Advanced reperfusion strategies for patients with out-of-hospital cardiac arrest and refractory ventricular fibrillation (ARREST): a phase 2, single center, open-label, randomized controlled trial. Lancet 2020 (LINK is HERE)
For More Thoughts on This Topic Checkout:
- Critical Care Now: It Takes a Village – A Community Approach to ECPR for OHCA (Part 1)
Post Peer Reviewed By: Zaf Qasim, MD (Twitter: @ResusOne)
