Effect of Intra-arrest Transport, Extracorporeal Cardiopulmonary Resuscitation, and Immediate Invasive Assessment and Treatment on Functional Neurologic Outcome in Refractory Out-of-Hospital Cardiac ArrestA Randomized Clinical Trial

Blog written by Dr Jose Chacko

Design and setting

The study was conducted over a 7.5-year period between 2013 to 2020 in the Prague region

A single-centre randomized controlled trial

Eligible subjects included adults aged 18 to 65 years receiving ongoing resuscitation for witnessed OHCA of presumed cardiac etiology

Minimum of 5 minutes of advanced cardiac life support without attaining ROSC

ECPR team was available at the cardiac centre

Stratified randomization into 4 strata: men/women; age 45 years or higher vs. less than 45 years. Block size of 8.

Exclusion

Unwitnessed cardiac arrest or underlying cause presumed to be the noncardiac origin

ROSC Attained ROSC within 5 minutes of resuscitation

Patient regained consciousness

Life-limiting comorbidities present

Bleeding diathesis

Do-not-resuscitate order

Prearrest Cerebral Performance Category (CPC) of 3 or greater

Pregnant or likelihood of pregnancy

Intervention

1. Early intra-arrest transport to the hospital using mechanical CPR (LUCAS)
2. ECPR
3. Patients were directly taken to the cath lab; ECPR if ROSC was not achieved in transit; other interventions were according to European Resuscitation Council guidelines
4. ECPR using a femoro-femoral approach
5. Intra-arrest intranasal evaporative cooling (available during the early phase of the study)
6. Immediate angiographic evaluation and treatment as appropriate

Control

Standard resuscitative interventions

Transport to the hospital if ROSC achieved

Early angiography and treatment

LUCAS could be used

Common to both

Hypothermia to 33C; 36C after the TTM trial

All other care according to the European Resuscitation Council guidelines

Crossover allowed

Standard to invasive: if requested by the emergency physician. At least 2 unsuccessful defibrillation attempts after randomization for crossover to the invasive arm

Invasive to standard if deemed futile

Termination of resuscitative interventions based on guidelines and judgment of the physician

Three sample sizes were calculated for a two-tailed α = .05 and 90% power

10% difference in primary outcome: 571

15% difference in primary outcome: 285

20% difference in primary outcome: 176

Terminated after 256 patients (124 vs. 132) for futility according to the recommendation of the data and safety board

ACS: 52% vs 48%

PE: 10% vs 9%

Myocarditis: 5% vs 2%

VF as initial rhythm: 58% vs 64%

pH: 6.93 vs 7.03

Lactate: 12.5 vs 10.4

TTM: 95% vs. 70%

Angiography: 98% vs. 77% (mostly coronary angiogram)

Successful PCI: 90% vs. 80%

Primary outcome

Survival at 180 days with a CPC 1 (able to work) or 2 neurological status (work in sheltered environment) invasive vs. standard

39/124 patients (31.5%) vs. 29 of 132 patients (22%).  OR; 1.63 [95% CI, 0.93 to 2.85]; absolute difference, 9.5% [95% CI, −1.3% to 20.1%]; P = .09)

Secondary outcomes

Survival at 30 d with no requirement for pharmacological or mechanical cardiac support

54/124 patients (43.5%) vs. 45/132 (34.1%)

(odds ratio, 1.49 [95% CI, 0.91 to 2.47]; absolute difference, 9.4% [95% CI, −2.5 to 21%]; P = .12).

Neurological recovery to CPC 1 or 2 at any point within the first 30 d

38/124 patients (30.6%) vs. 24 of 132 (18.2%)

(OR, 1.99 [95% CI, 1.11 to 3.57]; absolute difference, 12.4% [95% CI, 1.9% to 22.7%]; P = .02).

Survival at 180 days

Post hoc subgroup analysis for survival at 180 d with CPC 1 or 2

65 years or more vs. less

Gender

Location of cardiac arrest

Initial rhythm

pH below median value vs above

Lactate level below median value vs above

Cause of cardiac arrest

Adverse events

Any bleed: 31% vs. 15%

Fatal bleed: 11% vs. 0%

Intracranial bleed: 22% vs. 20%

Limitations –

Single centre study

Change in management – hypothermia, use of LUCAS

Underpowered

Higher than the expected 10% survival in the standard care group

The crossover was allowed – but this is in tune with real-world care

Summary – 

Very well conducted trial which questioned the “one size fits all” approach w.r.t eCPR in all patients with OOHCA.

There is still a place for eCPR in a select subgroup of patients, especially in high volume centres.