Moderate Hypothermia vs Normothermia and 30-Day Mortality in Patients With Cardiogenic Shock Receiving Venoarterial ECMO—Reply

Moderate Hypothermia vs Normothermia and 30-Day Mortality in Patients With Cardiogenic Shock Receiving Venoarterial ECMO

“…To the Editor The recently published HYPO-ECMO randomized clinical trial 1 showed no significant change in 30-day mortality with early application of hypothermia compared with strict normothermia in patients with refractory cardiogenic shock treated with venoarterial extracorporeal membrane oxygenation (ECMO). Even though the application of hypothermia has influenced medical thought for years, 2 evidence about hypothermia from randomized clinical trials in various settings is still conflicting.…”

“…3 We have some comments about the HYPO-ECMO trial. 1 First, we noticed that the majority of participating centers used Heater Unit 35 (Maquet Cardiopulmonary GmbH) to control the temperature for patients. Heater Unit 35 has a different principle of operation than a heater-cooler unit.…”

“…Heater Unit 35 has a different principle of operation than a heater-cooler unit. The hypothermia group in this trial 1 was already in a hypothermic state at the first temperature measurement. Therefore, the intervention group did not receive a hypothermia induction; rather, they received a hypothermia conservation, resulting in spontaneous temperature drifting due to the balance between rewarming induced by improved hemodynamics and heat loss through extracorporeal circulation.…”

“…4 Third, we would like to highlight several methodological concerns. The composite outcome of death and heart replacement therapies used in this trial 1 To the Editor I have several concerns about the recently published HYPO-ECMO trial. 1 First, I wonder whether this trial's exclusion of 72 patients who underwent cardiopulmonary resuscitation (CPR) for more than 45 minutes before initiation of ECMO was appropriate.…”

“…The composite outcome of death and heart replacement therapies used in this trial 1 To the Editor I have several concerns about the recently published HYPO-ECMO trial. 1 First, I wonder whether this trial's exclusion of 72 patients who underwent cardiopulmonary resuscitation (CPR) for more than 45 minutes before initiation of ECMO was appropriate. In a previous trial 2 comparing extracorporeal CPR with conventional treatment for patients with refractory ventricular fibrillation and out-of-hospital cardiac arrest, the average time from 911 call to initiation of ECMO in the extracorporeal CPR group was 59 minutes, and the rate of survival to discharge was 43% in the extracorporeal CPR group.…”