Effects of Blood Flow of Venoarterial Extracorporeal Membrane Oxygenation Life Support on Microcirculation

Study Overview
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Brief Summary
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Extra-corporeal membrane oxygenation (ECMO) life support system can provide both cardiac and respiratory support to patients with heart and respiratory failure. It can save time for these patients to regain organ function or to receive transplantation. Both the investigators' team and Ince et al. from the Netherland found that the microcirculatory dysfunction is more severe in ECMO non-survivors. The next step of research is to find out the key factors that affect microcirculation in ECMO patients. Because the blood flow supplied by the venoarterial ECMO (VA-ECMO) is directly related to macrocirculation, this study aims to investigate the effect of adjustment of VA-ECMO blood flow on microcirculation. The investigators hope that the results of this study can help the medical team to improve the quality of ECMO care.

Detailed Description
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After evaluation, explanation, and acquisition of agreement, the sublingual microcirculation will be examined within 24 h and at 48 h after placement of VA-ECMO. The VA-ECMO blood flow will be recorded, and the baseline microcirculation will be examined. After the ECMO technician adjusting the ECMO flow, sublingual microcirculation will be examined 2 minutes after each adjustment, and the change of ECMO blood flow will be recorded. When the ECMO team plans to weaning off the ECMO within 72 h, the sublingual microcirculation will be examined. The VA-ECMO blood flow will be reduced by ECMO technician, and sublingual microcirculation will be examined 2 minutes after each adjustment of the blood flow. The ECMO parameters, medications, and clinical data will be recorded, and the prognosis will be followed up on the 28th day.

Official Title
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Effects of Adjustment of Blood Flow of Venoarterial Extracorporeal Membrane Oxygenation Life Support on Microcirculation

Conditions
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Circulatory Failure

Intervention / Treatment
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* Device: Extra-corporeal membrane oxygenation life support


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who require venoarterial extra-corporeal membrane oxygenation (ECMO) life support Exclusion Criteria: who can not take an examination of sublingual microcirculation within 24 hours after placement of venoarterial ECMO support Non-native speakers

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: Extra-corporeal membrane oxygenation life support|Adjustment of blood flow of extra-corporeal membrane oxygenation life support|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perfused small vessel density | Perfused small vessel density [PSVD] measured by incident dark field video microscope | Difference of PSVD between before and after adjustment of VA-ECMO blood flow within 24 hours after placement of VA-ECMO | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perfused small vessel density | Perfused small vessel density [PSVD] measured by incident dark field video microscope | Difference of PSVD between before and after adjustment of VA-ECMO blood flow on day 2 after placement of VA-ECMO | 
| Perfused small vessel density | Perfused small vessel density measured by incident dark field video Perfused small vessel density [PSVD] measured by incident dark field video | Difference of PSVD between before and after adjustment of VA-ECMO blood flow within anticipated 72 hours before removal of VA-ECMO | 
| Total small vessel density | Total small vessel density [TSVD] measured by incident dark field video microscope | Difference of TSVD between before and after adjustment of VA-ECMO blood flow within 24 hours after placement of VA-ECMO | 
| Proportion of perfused vessel | Proportion of perfused vessel (PPV): TSVD/PSVD X 100 | Difference of PPV between before and after adjustment of VA-ECMO blood flow within 24 hours after placement of VA-ECMO |