ECPR for IHCAFor the critical outcome of favorable functional survival at 180 days or 1 year after IHCA, we identified very-low-quality evidence (downgraded for risk of bias from selection of cases for ECPR, crossover in treatments, and imprecision) from 2 non-RCTs,(Chen 2008, 554; Shin 2011, 1) comparing 144 patients treated with ECPR to 434 patients treated with conventional CPR. At 180 days, favorable outcome increased with ECPR (RR, 3.78; 95% CI, 2.26–6.31), even in propensity-matched samples.(Shin 2011, 1-7) At 1 year, favorable outcome was not different with ECPR (RR, 1.72; 95% CI, 0.74–4.01).For the critical outcome of survival to 30, 180 days, or 1 year after IHCA, we identified very-low-quality evidence (downgraded for risk of bias from selection of cases for ECPR, crossover in treatments, and imprecision) from 2 non-RCTs,(Chen 2008, 554; Shin 2011, 1) comparing 144 patients treated with ECPR to 434 patients treated with conventional CPR. These studies found improved survival at 30 days (RR, 2.25; 95% CI, 1.28–3.96) and 180 days (RR, 2.81; 95% CI, 1.79–4.39 and RR, 2.50; 95% CI, 1.31–4.80), but not 1 year (RR, 1.92; 95% CI, 0.88–4.15). A propensity-matched sample found improved survival at 180 days(Shin 2011, 1) (RR, 3.20; 95% CI, 1.25–8.18).For the important outcome of favorable functional survival at hospital discharge after IHCA, we identified very-low-quality evidence (downgraded for risk of bias from selection of cases for ECPR, crossover in treatments, and imprecision) from 2 non-RCTs,(Chen 2008, 554; Shin 2011, 1) comparing 144 patients treated with ECPR to 434 patients treated with conventional CPR. These studies found improved favorable outcome with ECPR (RR, 2.23; 95% CI, 1.11–4.52 and adjusted RR, 3.63; 95% CI, 2.18–6.02), even in propensity-matched samples (RR, 4.67; 95% CI, 1.41–15.41).(Shin 2011, 1)For the important outcome of survival to hospital discharge after IHCA, we identified very-low-quality evidence (downgraded for risk of bias from selection of cases for ECPR, crossover in treatments, and imprecision) from 2 non-RCTs,(Chen 2008, 554; Shin 2011, 1) comparing 144 patients treated with ECPR to 434 patients treated with conventional CPR. These studies found improved survival to hospital discharge in the entire cohort (RR, 2.33; 95% CI, 1.23–4.38 and RR, 2.81; 95% CI, 1.85–4.26). One of these studies found improved survival to hospital discharge in propensity-matched samples (RR, 3.17; 95% CI, 1.36–7.37).(Shin 2011, 1)ECPR for OHCAFor the critical outcome of favorable functional survival at 30, 90, or 180 days after OHCA, we identified very-low-quality evidence from 2 non-RCTs (downgraded for risk of bias for selection of cases for ECPR and imprecision), comparing 311 patients treated with ECPR to 312 patients treated with conventional CPR.(Maekawa 2013, 1186; Sakamoto 2014, 762) One study reported increased favorable outcome with ECPR at 30 days (RR, 7.92; 95% CI, 2.46–25.48) and 180 days (RR, 4.34; 95% CI, 1.71–11.00).(Sakamoto 2014, 762) The other study reported increased favorable outcome at 90 days (RR, 5.48; 95% CI, 1.52–19.84), but this association was not present in the propensity-matched sample (RR, 3.50; 95% CI, 0.81–15.16).(Maekawa 2013, 1186)For the critical outcome of survival to 30, 90, or 180 days after OHCA, we identified very-low-quality evidence (downgraded for risk of bias from selection of cases for ECPR and imprecision) from 2 non-RCTs, comparing 311 patients treated with ECPR to 312 patients treated with conventional CPR.(Maekawa 2013, 1186; Sakamoto 2014, 762) One study reported increased survival with ECPR at 30 days (RR, 3.94; 95% CI, 2.24–6.92) and 180 days (RR, 5.42; 95% CI, 2.65–11.09),(Sakamoto 2014, 762) and the other study reported increased survival with ECPR at 90 days (RR, 6.17; 95% CI, 2.37–16.07), even in a propensity-matched sample (RR, 4.50; 95% CI, 1.08–18.69).(Maekawa 2013, 1186)For the important outcome of favorable functional survival at hospital discharge after OHCA, we identified no comparative studies. For the important outcome of survival to hospital discharge after OHCA, we identified very-low-quality evidence (downgraded for risk of bias from selection of cases for ECPR and imprecision) from 1 non-RCT comparing 53 patients treated with ECPR to 109 patients treated with conventional CPR.(Maekawa 2013, 1186) Survival to hospital discharge was higher in patients treated with ECPR (RR, 4.99; 95% CI, 2.21–11.30), though not in propensity matched samples (RR, 3.00; 95% CI, 0.92–9.74).