Prognostic Predictors in Extracorporeal Membrane Oxygenation Treatment

Objective: The outcome of extracorporeal membrane oxygenation (ECMO) treatment
is always unpredictable when it is not indicated for neonatal respiratory diseases. A
prospective study was conducted to collect clinical, biochemical, immunological
parameters at variable times during an ECMO course to determine which factors
influenced ECMO outcome.
Methods: The patients’ demography, pre-ECMO conditions, biochemistry,
hematology, and arterial blood gas analysis during ECMO treatment, were recorded
along with the duration, outcome and complications of the treatment. Blood was
collected on the 3rd and 6th days after initiation of ECMO for cytokines study.
Results: Fifty patients who were receiving ECMO for acute cardio/pulmonary failure
were studied; 32 were male, and 18 were female. Their ages ranged from 20 days to
84 years; their body weights ranged from 2.4 kg to 95 kg. ECMO was set up in
operation rooms (n=20), intensive care units (n=18), cardiac catheterization rooms
(n=3), emergency rooms (n=3), and outside hospitals (n=6). The indications of
ECMO treatment included postcardiotomy cardiogenic shock (n=27), acute
myocarditis (n=5), myocardial infarction that required resuscitation (n=7),
cardiomyopathy with cardiogenic shock (n=2), acute respiratory distress syndrome
(n=5), and others (n=4). Eleven patients died within 48 hours following initiation of
ECMO. The etiologies of mortality included extremely poor heart function (n=5),
severe shock damage (n=5), and uncontrollable bleeding (n=1). Three patients died of
brain death due to ECMO mechanical failure (n=1) or intracranial hemorrhage while
on the ECMO (n=2). Sixteen patients underwent a successful ECMO treatment, but
three of them died suddenly months later. Only 2 of 16 successful ECMO patients
needed ECMO support for more than five days. The ECMO treatment of 20 patients
failed and the patients died of multiple organs failure whether or not they were
weaned off ECMO. Comparing instances of successful ECMO with those of failed
ECMO by multiple logistic regression, revealed that three independent factors, acute
renal failure at the time of ECMO set-up, sepsis during ECMO, lower IL-12 serum
level on the 3rd day, predicted a failed ECMO treatment.
Conclusion: ECMO is an ideal rescue treatment for acute cardio/pulmonary failure,
but a successful ECMO treatment requires the following: 1. Acute cardiopulmonary
failure treated by ECMO must be rapidly reversible. ECMO is not intended for
prolonged treatment. 2. No severe shock damage must have occurred due to
underlying diseases before ECMO support is begun. 3. No complications can occur
during ECMO.