[Application of pump-controlled retrograde trial off in weaning from veno-arterial extracorporeal membrane oxygenation in adult patients].

Objective: To Summarize the experience of pump-controlled retrograde trial off (PCRTO) in the process of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) withdrawal in adult patients. Methods: Adult patients who received ECMO assistance in Intensive Care Unit for Cardiac Surgery from March to July 2019 were collected. According to our strategies, PCRTO was used if the patients can wean from VA-ECMO and hemodynamic indexes were recorded during the process. The statistics data was collected, including the 48 hours survival rate, ECMO re-assistance rate, thrombus complications, Intensive Care Unit (ICU) stay time and hospital stay time after weaning from VA-ECMO. The patients who failed in the test were continued to be assisted by ECMO. Results: There were 46 patients assisted by VA-ECMO in our center. In total, 21 adults who met the offline test standard underwent 26 PCRTOs, including 10 male adults (47.6%), with an age of 65 (55, 68) years old. Eighteen adults passed the withdrawal test. No new thrombus was found in the arteriovenous ultrasound of the lower extremity after weaning from ECMO, and no pulmonary embolism was found in the chest X-ray. The success rate of weaning from ECMO was 69.23%(18/26). The D-dimer decreased [584(348,2 107)µg/L vs 1 440(631,2 916)µg/L, P=0.014] and the left ventricular ejection fraction (LVEF) increased (51.4%±8.5% vs 46.9%±10.6%, P=0.013) on the next day after weaning. There were significant differences in heart rate (HR), central venous pressure (CVP), oxygenation index and lactate (Lac) during the PCRTO in the group which involved the cases of the 8 failed experiments (all P<0.05). Compared with the failure group, there were significant differences in age, blood flow rate, CVP before the test, HR, pulse oxygen saturation(SpO(2)), CVP, Lac and oxygenation index after the test, and the variations of SpO(2), CVP and Lac. Conclusion: PCRTO is a simple, reversible, safe and effective weaning method. It can be used in the process of VA-ECMO withdrawal in adult patients.

Weaning adult patients with cardiogenic shock on veno-arterial extracorporeal membrane oxygenation by pump-controlled retrograde trial off.

BACKGROUND: There is a lack of consensus on the timing of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) liberation. VA-ECMO weaning usually consists of serial decrements until an idling flow is achieved, supported by echocardiographic and haemodynamic assessments. Even with minimal idling flow, right ventricular (RV) preload is reduced and, hence, right heart function is not fully tested under adequate loading conditions. Following the use of a novel technique called Pump Controlled Retrograde Trial Off (PCRTO) in neonate VA-ECMO weaning, we report the use of this technique in seven adult patients on VA-ECMO. METHODS: We retrospectively reviewed all adult VA-ECMO patients treated at a tertiary teaching hospital in Hong Kong since 2010. Clinical data, including diagnosis, echocardiography findings, ECMO configuration, PCRTO settings, survival after veno-arterial ECMO (SAVE) score and outcomes, were collected. Mortality and death due to cardiac failure was compared between PCRTO and conventional weaning. RESULTS: Seven patients underwent PCRTO, with a mean SAVE score of -4.4 ± 5.9. All seven patients were successfully decannulated without haemodynamic deterioration. In all cases, no clots or fibrin deposits were found in the circuit after the trial. There was no difference in mean SAVE scores among the seven patients in PCRTO and the 23 patients in the conventional group (-3.6, 95% CI -8.8 to 1.5). The number of deaths due to cardiac failure in the PCRTO group and the conventional group were 0 and 3, respectively (0% vs. 13%, p=0.99). Mortality after decannulation for PCRTO was 42.9% vs. conventional weaning 34.8% (p=0.99). CONCLUSION: Our study suggests that PCRTO is a simple, safe and reversible alternative weaning method. It may have a particular role in the assessment of patients who have marginal recovery and right heart failure. Prospective controlled studies are needed to establish the potential role of PCRTO in the liberation of patients from VA-ECMO support.