Factors for Weaning From a Percutaneous Cardiopulmonary Support System (PCPS) in Patients With Severe Cardiac Failure A Comparative Study in Weaned and Nonweaned Patients

Parameters associated with successful weaning of veno-arterial extracorporeal membrane oxygenation: a systematic review

PURPOSE

Veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) can be used to restore organ perfusion in patients with cardiogenic shock until native heart recovery occurs. It may be challenging, however, to determine when patients can be weaned successfully from ECMO-surviving without requiring further mechanical support or heart transplant. We aimed to systematically review the medical literature to determine the biomarkers, hemodynamic and echocardiographic parameters associated with successful weaning of VA-ECMO in adults with cardiogenic shock and to present an evidence-based weaning algorithm incorporating key findings.

METHOD

We systematically searched PubMed, Embase, ProQuest, Google Scholars, Web of Science and the Grey literature for pertinent original research reports. We excluded studies limited to extracorporeal cardiopulmonary resuscitation (ECPR) as the neurological prognosis may significantly alter the decision-making process surrounding the device removal in this patient population. Studies with a mixed population of VA-ECMO for cardiogenic shock or cardiac arrest were included. We excluded studies limited to patients in which ECMO was only used as a bridge to VAD or heart transplant, as such patients are, by definition, never "successfully weaned." We used the Risk of Bias Assessment tool for Non-Randomized Studies. The study was registered on the International prospective register of systematic reviews (PROSPERO CRD42020178641).

RESULTS

We screened 14,578 records and included 47 that met our pre-specified criteria. Signs of lower initial severity of shock and myocardial injury, early recovery of systemic perfusion, left and right ventricular recovery, hemodynamic and echocardiographic stability during flow reduction trial and/or pump-controlled retrograde trial off predicted successful weaning. The most widely used parameter was the left ventricular outflow tract velocity time integral, an indicator of stroke volume. Most studies had a moderate or high risk of bias. Heterogeneity in methods, timing, and conditions of measurements precluded any meta-analysis.

CONCLUSIONS

In adult patients on VA-ECMO for cardiogenic shock, multiple biomarkers, hemodynamic and echocardiographic parameters may be used to track resolution of systemic hypoperfusion and myocardial recovery in order to identify patients that can be successfully weaned.

Predictive factors for successful weaning from percutaneous cardiopulmonary support in patients with cardiogenic shock complicating acute myocardial infarction

BACKGROUND AND PURPOSE

Percutaneous cardiopulmonary support (PCPS) is useful in the rescue of patients who have experienced severe cardiogenic shock. We investigated the predictive factors of survival among patients with cardiogenic shock requiring PCPS.

METHODS AND SUBJECTS

We enrolled 29 patients (21 men and 8 women, 73 ± 10 years old) with circulatory collapse complicating acute myocardial infarction (AMI) requiring PCPS. Fifteen patients could be weaned from PCPS and survived for more than 1 month (group A), while the other 14 patients could not (group B). We investigated the initial PCPS settings, and performed the appropriate laboratory tests. Hemodynamic data and arterial base excess (BE) values were recorded throughout the PCPS treatment.

RESULTS

There was no difference in the laboratory test results or the left ventricular ejection fraction between the groups at the start of PCPS. PCPS flow (l/min) was significantly lower in group A than in group B at the 24th hour of PCPS (2.26 ± 0.36 and 2.54 ± 0.41, respectively). There were no differences in blood pressure between the groups. During the 24-h period prior to the end of PCPS, BE remained almost normal in group A. In group B, BE decreased continuously throughout the same period. BE values were significantly lower compared to those obtained in group A 12h prior to the end of PCPS.

CONCLUSIONS

A reduction in PCPS flow without hemodynamic collapse may allow for successful weaning from PCPS. BE may be a potent factor in determining when to terminate PCPS.