Introduction:
Extracorporeal membrane oxygenation (ECMO) is increasingly used to support patients with refractory ventricular fibrillation/ventricular tachycardia (rVF/VT) out-of-hospital cardiac arrest (OHCA). Los Angeles County (LAC) operates a regional system of care for 10.2 million persons, routing patients with OHCA to the closest cardiac receiving center. The purpose of this study was to determine 1) the number of patients eligible and 2) the potential for increased neurologically intact survival routing patients with rVF/VT OHCA to ECMO-capable cardiac centers.
Methods:
This was a retrospective study utilizing LAC quality improvement databases. Patients 18-75 years treated by EMS from 2011-2017 for rVF/VT OHCA, defined as persistent VF/VT after 3 defibrillations, were included in the analysis. Actual survival with good neurologic outcome, defined as cerebral performance category (CPC) 1 or 2, was abstracted from the LAC OHCA Registry. Theoretical patient outcome with routing directly to an ECMO-capable center was determined by applying outcomes as described by the Minnesota Resuscitation Consortium (MRC) for rVF/VT transported for ECMO. Assumptions included the availability of ECMO within a 30-minute transport time, and similar proportions of patients meeting criteria for transport/cannulation and surviving with CPC 1-2 as the MRC cohort, 78% and 40% respectively. For the remaining patients, we assumed no change in outcome. We compared the actual to the theoretical outcome with regional ECMO to determine the annual increase in survival with good neurologic outcome.
Results:
During the 7-year study period, there were 1862 patients with rVT/VT OHCA with outcomes available for 1454 (78%) patients. Median age was 59 years (IQR 51-66); 76% were male. Actual survival with CPC 1-2 was 13% (187 patients). Theoretical survival with CPC 1-2 in a regional ECMO-capable system was 34% (495 patients); OR 3.5 (95%CI 2.9-4.2), p<0.0001 with ECMO routing versus without.
Conclusion:
Assuming ECMO availability within a 30-minute transport time throughout the regional system, routing patients with rVF/VT to ECMO-capable centers could improve survival with CPC 1-2 nearly three-fold and result in 44 additional patients/year with meaningful survival.
THE ISSUE OF AGGRESSION IN PATIENTS WITH VENTRICULAR TACHYCARDIA WITH PULSE AND A SHORT EPISODE OF CARDIAC ARREST — A CASE OF A 68-YEAR-OLD MALE
