Membranes for extracorporeal membrane oxygenator(ECMO): History,preparation, modification and mass transfer

Extracorporeal membrane oxygenator(ECMO) has been in development for nearly 70 years, and the oxygenator has gone through several generations of optimizations, with advances from bubble oxygenators to membrane oxygenators leading to more and more widespread use of ECMO. Membrane is the core of a ECMO system and the working mechanism of membrane oxygenator depends on the membrane material,from PDMS flat membrane to PMP hollow fiber membrane, which have experienced three generations.Blood compatibility on the surface of the membrane material is very vital, which directly determines the use duration of the oxygenator and can reduce the occurrence of complications. The mechanism of mass transfer is the basis of oxygenator operation and optimization. This review summarizes the membrane development history and preparation technology, modification approaches and mass transfer theory in the process of oxygen and blood exchange. We hoped that this review will provide more ideas for the study of gas blood exchange membrane.

Severe aconite poisoning successfully treated with veno-arterial extracorporeal membrane oxygenation:A case report

BACKGROUND Most species of aconite contain highly toxic aconitines,the oral ingestion of which can be fatal,primarily because they cause ventricular arrhythmias.We describe a case of severe aconite poisoning that was successfully treated through venoarterial extracorporeal membrane oxygenation(VA-ECMO)and in which detailed toxicological analyses of the aconite roots and biological samples were performed using liquid chromatography-tandem mass spectrometry(LC-MS/MS).CASE SUMMARY A 23-year-old male presented to the emergency room with circulatory collapse and ventricular arrhythmia after ingesting approximately half of a root labeled,“Aconitum japonicum Thunb”.Two hours after arrival,VA-ECMO was initiated as circulatory collapse became refractory to antiarrhythmics and vasopressors.Nine hours after arrival,an electrocardiogram revealed a return to sinus rhythm.The patient was weaned off VA-ECMO and the ventilator on hospital days 3 and 5,respectively.On hospital day 15,he was transferred to a psychiatric hospital.The other half of the root and his biological samples were toxicologically analyzed using LC-MS/MS,revealing 244.3 mg/kg of aconitine and 24.7 mg/kg of mesaconitine in the root.Serum on admission contained 1.50 ng/mL of aconitine.Beyond hospital day 2,neither were detected.Urine on admission showed 149.09 ng/mL of aconitine and 3.59 ng/mL of mesaconitine,but these rapidly decreased after hospital day 3.CONCLUSION The key to saving the life of a patient with severe aconite poisoning is to introduce VA-ECMO as soon as possible.

Accidental placement of venous return catheter in the superior vena cava during venovenous extracorporeal membrane oxygenation for severe pneumonia: A case report

BACKGROUND Venovenous extracorporeal membrane oxygenation(V-V ECMO)has become an important treatment for severe pneumonia,but there are various complications during the treatment.This article describes a case with severe pneumonia success-fully treated by V-V ECMO,but during treatment,the retrovenous catheter,which was supposed to be in the right internal vein,entered the superior vena cava directly in the mediastinum.The ECMO was safely withdrawn after multidiscip-linary consultation.Our experience with this case is expected to provide a reference for colleagues who will encounter similar situations.CASE SUMMARY A 64-year-old man had severe pulmonary infection and respiratory failure.He was admitted to our hospital and was given ventilation support(fraction of inspired oxygen 100%).The respiratory failure was not improved and he was treated by V-V ECMO,during which the venous return catheter,which was supposed to be in the right internal vein,entered the superior vena cava directly in the mediastinum.There was a risk of massive mediastinal bleeding if the catheter was removed directly when the ECMO was withdrawn.Finally,the patient underwent vena cava angiography+balloon attachment+ECMO with-drawal in the operating room(prepared for conversion to thoracotomy for vascular exploration and repair at any time during surgery)after multidiscip-linary consultation.ECMO was safely withdrawn,and the patient recovered and was discharged.CONCLUSION Patients may have different vascular conditions.Multidisciplinary cooperation can ensure patient safety.Our experience will provide a reference for similar cases.

Left ventricular thrombosis caused cerebral embolism during venoarterial extracorporeal membrane oxygenation support: A case report

BACKGROUND Venoarterial(VA)extracorporeal membrane oxygenation(ECMO),an effective short-term circulatory support method for refractory cardiogenic shock,is widely applied.However,retrospective analyses have shown that VA-ECMO-assisted cases were associated with a relatively high mortality rate of approximately 60%.Embolization in important organs caused by complications of left ventricular thrombosis(LVT)during VA-ECMO is also an important reason.Although the incidence of LVT during VA-ECMO is not high,the consequences of embolization are disastrous.CASE SUMMARY A 37-year-old female patient was admitted to hospital because of fever for 4 d and palpitations for 3 d.After excluding the diagnosis of coronary heart disease,we established a diagnosis of“clinically explosive myocarditis”.The patient still had unstable hemodynamics after drug treatment supported by VA-ECMO,with heparin for anticoagulation.On day 4 of ECMO support,a left ventricular thro-mbus attached to the papillary muscle root of the mitral valve was found by transthoracic echocardiography.Left ventricular decompression was performed and ECMO was successfully removed,but the patient eventually died of multiple cerebral embolism.CONCLUSION LVT with high mobility during VA-ECMO may cause embolism in important organs.Therefore,a"wait and see"strategy should be avoided.

Cerebral pseudoinfarction due to venoarterial extracorporeal membrane oxygenation:A case report

BACKGROUND Neurological complications are common in the management of venoarterial extracorporeal membrane oxygenation(VA-ECMO),with most patients requiring sedation and intubation,limiting the assessment of neurological function.Therefore,we must rely on advanced neuroimaging techniques,such as computed tomography angiography(CTA)and computed tomography perfusion(CTP).Because ECMO changes the normal blood flow pattern,it may interfere with the contrast medium in some special cases,leading to artifacts and ultimately misleading clinical decisions.CASE SUMMARY A 61-year-old man presented to a local hospital with chest tightness and pain 1 d prior to presentation.The patient was treated with VA-ECMO after sudden cardiac and respiratory arrest at a local hospital.For further treatment,the patient was transferred to our hospital.The initial consciousness assessment was not clear,and routine CTP was performed to understand the intracranial changes,which suggested a large area of cerebral infarction on the right side;however,the cerebral oxygen was not consistent with the CTP results,and the reexamination of CTA still suggested a right cerebral infarction.To identify this difference,bedside transcranial Doppler was performed,and the blood flow on both sides was different.By reducing the ECMO flow,CTP reexamination showed that the results were normal and consistent with the clinical results.On day 3,the patient was alert and showed good limb movements.CONCLUSION In patients with peripheral VA-ECMO,cerebral perfusion confirmed by CTP and CTA may lead to false cerebral infarction.

Veno-arterial extracorporeal membrane oxygenation for the treatment of obstructive shock caused by venous air embolism:A case report

BACKGROUND Venous air embolism(VAE)is a potentially lethal condition,with a reported incidence rate of about 0.13%,and the true incidence may be higher since many VAE are asymptomatic.The current treatments for VAE include Durant's maneuver,aspiration and removal of air through venous catheters,and hyperbaric oxygen therapy.For critically ill patients,use of cardiotonic drugs and chest compressions remain useful strategies.The wider availability of extracorporeal membrane oxygenation(ECMO)has brought a new option for VAE patients.CASE SUMMARY A 53-year-old female patient with VAE presented to the emergency clinic due to abdominal pain with fever for 1 d and unconsciousness for 2 h.One day ago,the patient suffered from abdominal pain,fever,and diarrhea.She suddenly became unconscious after going to the toilet during the intravenous infusion of ciprofloxacin 2 h ago,accompanied by nausea and vomiting,during which a small amount of gastric contents were discharged.She was immediately sent to a local hospital,where cranial and chest computed tomography showed bilateral pneumonia as well as accumulated air visible in the right ventricle and pulmonary artery.The condition deteriorated despite endotracheal intubation,rehydration,and other treatments,and the patient was then transferred to our hospital.Veno-arterial ECMO was applied in our hospital,and the patient's condition gradually improved.The patient was successfully weaned from ECMO and extubated after two days.CONCLUSION ECMO may be an important treatment for patients with VAE in critical condition.

Extracorporeal membrane oxygenation states basilar artery thrombectomy and left posterior cerebral artery stent thrombectomy:A case report

BACKGROUND Extracorporeal membrane oxygenation(ECMO)is a new type of extracorporeal respiratory and circulatory assistance device.It can drain venous blood out of the body and inject it into veins or arteries after being oxygenated by an oxygenator(membrane lung)to replace lung and heart functions in a short time.ECMO can provide tissue blood perfusion and gas exchange almost equivalent to cardiac output and extend the effective treatment time window for patients with acute circulatory failure to restore cardiopulmonary function.CASE SUMMARY We report a case of an 81-year-old woman who underwent whole cerebral angiography,basilar artery thrombectomy and stent thrombectomy in the posterior artery of the left brain after implantation of ECMO.The patient was admitted to the hospital due to myocardial infarction.Considering that the cause of the patient’s disturbance of consciousness was unknown and cerebrovascular accident could not be ruled out after the implantation of ECMO,the department of Radioactive Intervention performed cerebral angiography.And the result of the angiography indicated vascular occlusion.After the basilar artery thrombectomy and stent thrombectomy in the posterior artery of the left brain,the patency of the occlusive vessel was achieved.CONCLUSION Although the patient eventually died of circulatory failure,the result of this case verifies the feasibility of cerebral angiography and thrombectomy in patients with implanted ECMO in the intubated state.

New therapeutic strategy with extracorporeal membrane oxygenation for refractory hepatopulmonary syndrome after liver transplant: A case report

BACKGROUND Due to the lack of published literature about treatment of refractory hepatopulmonary syndrome(HPS)after liver transplant(LT),this case adds information and experience on this issue along with a treatment with positive outcomes.HPS is a complication of end-stage liver disease,with a 10%-30%incidence in cirrhotic patients.LT can reverse the physiopathology of this process and restore normal oxygenation.However,in some cases,refractory hypoxemia persists,and extracorporeal membrane oxygenation(ECMO)can be used as a rescue therapy with good results.CASE SUMMARY A 59-year-old patient with alcohol-related liver cirrhosis and portal hypertension was included in the LT waiting list for HPS.He had good liver function(Model for End-Stage Liver Disease score 12,Child-Pugh class B7).He had pulmonary fibrosis and a mild restrictive respiratory pattern with a basal oxygen saturation of 82%.The macroaggregated albumin test result was>30.Spirometry demonstrated a forced expiratory volume in one second(FEV1)of 78%,forced vital capacity(FVC)of 74%,FEV1/FVC ratio of 81%,diffusion capacity for carbon monoxide of 42%,and carbon monoxide transfer coefficient of 57%.He required domiciliary oxygen at 2 L/min(16 h/d).The patient was admitted to the intensive care unit(ICU)and extubated in the first 24 h,needing high-flow therapy and non-invasive ventilation and inhaled nitric oxide afterwards.Reintubation was needed after 72 h.Due to the non-response to supportive therapies,installation of ECMO was decided with progressive recovery after 9 d.Extubation was possible on the tenth day,maintaining a high-flow nasal cannula and de-escalating to conventional oxygen therapy after 48 h.He was discharged from ICU on postoperative day(POD)20 with a 90%-92%oxygen saturation.Steroid recycling was needed twice for acute rejection.The patient was discharged from hospital on POD 27 with no symptoms,with an 89%-90%oxygen saturation.CONCLUSION Due to the favorable results observed,ECMO could become the central axis of treatment of HPS and refractory hypoxemia after LT.

The Performance of Extracorporeal Membrane Oxygenation in Various Viral Pneumonia Pandemics: A Meta-Analysis and Systematic Review

Objective: To compare the effects of extracorporeal membrane oxygenation (ECMO) and routine mechanical ventilation on mortality and the risk of associated adverse events in patients with severe viral pneumonia. Methods: PubMed, the Cochrane Library, Embase, Web of Science, and other databases were searched to collect case-control or cohort studies on prognoses associated with ECMO treatment for viral pneumonia. Search terms included extracorporeal membrane oxygenation, ECMO, viral pneumonia, COVID-19, influenza, MERS, and others. According to the PICOS principle, two evaluators independently screened the literature, extracted the data, cross-checked the data, and extracted the data again. Two researchers evaluated the risk of bias in the included studies according to the Newcastle-Ottawa Scale (NOS) and cross-checked the results. Meta-analysis was performed using RevMan 5.3 software. Results: Nine studies were included for analysis, encompassing a total of 4,330 patients, which were categorized into ECMO and CMV groups. There were no significant differences between the two groups in most baseline data;however, the ECMO group had a lower oxygenation index, and some studies reported higher SOFA scores in the ECMO group compared to the CMV group. There was no significant difference in in-hospital mortality between the two groups. The length of ICU stay, total hospital stay, and total mechanical ventilation time were longer in the ECMO group than in the CMV group. In terms of adverse events, there was no significant difference in the occurrence of kidney injury between the two groups. Bleeding events were reported in two studies, with more bleeding events occurring in the ECMO group. According to the subgroup analysis of different virus types, there were no statistical differences in the above aspects among patients with swine flu, novel coronavirus, and MERS. Conclusion: ECMO has a certain degree of positive significance in the treatment of severe viral pneumonia, but there is no significant difference in the treatment outcome of ECMO across different epidemic periods. The timing of ECMO treatment, patient management, and withdrawal evaluation still need further research.

Successful treatment of veno-arterial extracorporeal membrane oxygenation complicated with left ventricular thrombus by intravenous thrombolysis:A case report

BACKGROUND Left ventricular thrombus is a rare condition,for which appropriate treatments are not extensively studied.Although it can be treated by thrombectomy,such surgery can be difficult and risky,and not every patient can tolerate the surgery.CASE SUMMARY We report a case of a middle-aged man receiving veno-arterial extracorporeal membrane oxygenation(VA-ECMO)for acute myocardial infarction who developed left ventricular thrombus despite systemic anticoagulation.After systemic thrombolysis with urokinase,the left ventricular thrombus disappeared,ECMO was successfully withdrawn 9 days later,and the patient recovered and was discharged from hospital.CONCLUSION Systemic thrombolysis is a treatment option for left ventricular thrombus in addition to anticoagulation and thrombectomy.

Anesthesia for extracorporeal membrane oxygenation-assisted thoracoscopic lower lobe subsegmental resection in a patient with a single left lung:A case report

BACKGROUND It is difficult and risky for patients with a single lung to undergo thoracoscopic segmental pneumonectomy,and previous reports of related cases are rare.We introduce anesthesia for Extracorporeal membrane oxygenation(ECMO)-assisted thoracoscopic lower lobe subsegmental resection in a patient with a single left lung.CASE SUMMARY The patient underwent comprehensive treatment for synovial sarcoma of the right lung and nodules in the lower lobe of the left lung.Examination showed pulmonary function that had severe restrictive ventilation disorder,forced expiratory volume in 1 second of 0.72 L(27.8%),forced vital capacity of 1.0 L(33%),and maximal voluntary ventilation of 33.9 L(35.5%).Lung computed tomography showed a nodular shadow in the lower lobe of the left lung,and lung metastasis was considered.After multidisciplinary consultation and adequate preoperative preparation,thoracoscopic left lower lung lobe S9bii+S10bii combined subsegmental resection was performed with the assistance of total intravenous anesthesia and ECMO intraoperative pulmonary protective ventilation.The patient received postoperative ICU supportive care.After surgical treatment,the patient was successfully withdrawn from ECMO on postoperative Day 1.The tracheal tube was removed on postoperative Day 4,and she was discharged from the hospital on postoperative Day 15.CONCLUSION The multi-disciplinary treatment provided maximum medical optimization for surgical anesthesia and veno-venous ECMO which provided adequate protection for the patient's perioperative treatment.

Treatment of a patient with aconitine poisoning using veno-arterial membrane oxygenation:A case report

BACKGROUND Aconitine poisoning is highly prone to causing malignant arrhythmias.The elimination of aconitine from the body takes a considerable amount of time,and during this period,patients are at a significant risk of death due to malignant arrhythmias associated with aconitine poisoning.CASE SUMMARY A 30-year-old male patient was admitted due to accidental ingestion of aconitinecontaining drugs.Upon arrival at the emergency department,the patient intermittently experienced malignant arrhythmias including ventricular tachycardia,ventricular fibrillation,ventricular premature beats,and cardiac arrest.Emergency interventions such as cardiopulmonary resuscitation and defibrillation were promptly administered.Additionally,veno-arterial extracorporeal membrane oxygenation(VA-ECMO)therapy was initiated.Successful resuscitation was achieved before ECMO placement,but upon initiation of ECMO,the patient experienced recurrent malignant arrhythmias.ECMO was utilized to maintain hemodynamics and respiration,while continuous blood purification therapy for toxin clearance,mechanical ventilation,and hypothermic brain protection therapy were concurrently administered.On the third day of VA-ECMO support,the patient’s respiratory and hemodynamic status stabilized,with only frequent ventricular premature beats observed on electrocardiographic monitoring,and echocardiography indicated recovery of cardiac contractile function.On the fourth day,a significant reduction in toxin levels was observed,along with stable hemodynamic and respiratory functions.Following a successful pump-controlled retrograde trial occlusion test,ECMO assistance was terminated.The patient gradually improved postoperatively and achieved recovery.He was discharged 11 days later.CONCLUSION VA-ECMO can serve as a bridging resuscitation technique for patients with reversible malignant arrhythmias.

Extracorporeal Membrane Oxygenation Therapy for Critically Ill Coronavirus Disease 2019 Patients in Wuhan,China:A Retrospective Multicenter Cohort Study

Currently,little in-depth evidence is known about the application of extracorporeal membrane oxygenation(ECMO)therapy in coronavirus disease 2019(COVID-19)patients.This retrospective multicenter cohort study included patients with COVID-19 at 7 designated hospitals in Wuhan,China.The patients were followed up until June 30,2020.Univariate and multivariate logistic regression analyses were performed to identify the risk factors associated with unsuccessful ECMO weaning.Propensity score matching was used to match patients who received veno-venous ECMO with those who received invasive mechanical ventilation(IMV)-only therapy.Of 88 patients receiving ECMO therapy,27 and 61 patients were and were not successfully weaned from ECMO,respectively.Additionally,15,15,and 65 patients were further weaned from IMV,discharged from hospital,or died during hospitalization,respectively.In the multivariate logistic regression analysis,a lymphocyte count≤0.5×10^(9)/L and D-dimer concentration>4×the upper limit of normal level at ICU admission,a peak PaCO_(2)>60 mmHg at 24 h before ECMO initiation,and no tracheotomy performed during the ICU stay were independently associated with lower odds of ECMO weaning.In the propensity scorematched analysis,a mixed-effect Cox model detected a lower hazard ratio for 120-day all-cause mortality after ICU admission during hospitalization in the ECMO group.The presence of lymphocytopenia,higher D-dimer concentrations at ICU admission and hypercapnia before ECMO initiation could help to identify patients with a poor prognosis.Tracheotomy could facilitate weaning from ECMO.ECMO relative to IMV-only therapy was associated with improved outcomes in critically ill COVID-19 patients.

Massive pulmonary haemorrhage due to severe trauma treated with repeated alveolar lavage combined with extracorporeal membrane oxygenation:A case report

BACKGROUND Massive pulmonary haemorrhage can spoil the entire lung and block the airway in a short period of time due to severe bleeding,which quickly leads to death.Alveolar lavage is an effective method for haemostasis and airway maintenance.However,patients often cannot tolerate alveolar lavage due to severe hypoxia.We used extracorporeal membrane oxygenation(ECMO)to overcome this limitation in a patient with massive pulmonary haemorrhage due to severe trauma and succeeded in saving the life by repeated alveolar lavage.CASE SUMMARY A 22-year-old man sustained multiple injuries in a motor vehicle accident and was transferred to our emergency department.On admission,he had a slight cough and a small amount of bloody sputum;computed tomography revealed multiple fractures and mild pulmonary contusion.At 37 h after admission,he developed severe chest tightness,chest pain,dizziness and haemoptysis.His oxygen saturation was 68%.Emergency endotracheal intubation was performed,and a large amount of bloody sputum was suctioned.After transfer to the intensive care unit,he developed refractory hypoxemia and heparin-free venovenous ECMO was initiated.Fibreoptic bronchoscopy revealed diffuse and profuse blood in all bronchopulmonary segment.Bleeding was observed in the trachea and right bronchus,and repeated alveolar lavage was performed.On day 3,the patient’s haemoptysis ceased,and ECMO support was terminated 10 d later.Tracheostomy was performed on day 15,and the patient was weaned from the ventilator on day 21.CONCLUSION Alveolar lavage combined with ECMO can control bleeding in trauma-induced massive pulmonary haemorrhage,is safe and can be performed bedside.

Extracorporeal membrane oxygenation in lung transplantation:Indications,techniques and results

The use of extracorporeal membrane oxygenation(ECMO)in the field of lung transplantation has rapidly expanded over the past 30 years.It has become an important tool in an increasing number of specialized centers as a bridge to transplantation and in the intra-operative and/or post-operative setting.ECMO is an extremely versatile tool in the field of lung transplantation as it can be used and adapted in different configurations with several potential cannulation sites according to the specific need of the recipient.For example,patients who need to be bridged to lung transplantation often have hypercapnic respiratory failure that may preferably benefit from veno-venous(VV)ECMO or peripheral veno-arterial(VA)ECMO in the case of hemodynamic instability.Moreover,in an intraoperative setting,VV ECMO can be maintained or switched to a VA ECMO.The routine use of intra-operative ECMO and its eventual prolongation in the postoperative period has been widely investigated in recent years by several important lung transplantation centers in order to assess the graft function and its potential protective role on primary graft dysfunction and on ischemia-reperfusion injury.This review will assess the current evidence on the role of ECMO in the different phases of lung transplantation,while analyzing different studies on pre,intra-and post-operative utilization of this extracorporeal support.

Predicting factors for the need of extracorporeal membrane oxygenation for suicide attempts by cardiac medication:a single-center cohort study

BACKGROUND:Severe poisoning due to the overdosing of cardiac drugs can lead to cardiovascular failure.In order to decrease the mortality rate,the most severe patients should be transferred as quickly as possible to an extracorporeal membrane oxygenation(ECMO)center.However,the predictive factors showing the need for venous-arterial ECMO(VA-ECMO)had never been evaluated.METHODS:A retrospective,descriptive,and single-center cohort study.All consecutive patients admitted in the largest ICU of Reunion Island(Indian Ocean)between January 2013 and September 2018 for beta-blockers(BB),calcium channel blockers(CCB),renin-angiotensin-aldosterone system blockers,digoxin or anti-arrythmic intentional poisonings were included.ECMO implementation was the primary outcome.RESULTS:A total of 49 consecutive admissions were included.Ten patients had ECMO,39 patients did not have ECMO.Three patients in ECMO group died,while no patients in the conventional group died.The most relevant ECMO-associated factors were pulse pressure and heart rate at first medical contact and pulse pressure,heart rate,arterial lactate concentration,liver enzymes and left ventricular ejection fraction(LVEF)at ICU-admission.Only pulse pressure at first medical contact and LVEF were significant after logistic regression.CONCLUSION:A transfer to an ECMO center should be considered for a pulse pressure<35 mmHg at first medical contact or LVEF<20%on admission to ICU.

Mortality in patients with COVID-19 requiring extracorporeal membrane oxygenation:A meta-analysis

BACKGROUND Coronavirus disease 2019(COVID-19)has become a worldwide pandemic and significant public health issue.The effectiveness of extracorporeal membrane oxygenation(ECMO)in treating COVID-19 patients has been called into question.AIM To conduct a meta-analysis on the mortality of COVID-19 patients who require ECMO.METHODS This analysis adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes 2020(PRISMA)and has been registered at the International Prospective Register of Systematic Reviews(number CRD42020227414).A quality assessment for all the included articles was performed by the Newcastle-Ottawa Scale(NOS).Studies with tenor more COVID-19 patients undergoing ECMO were included.The random-effects model was used to obtain the pooled incidence of mortality in COVID-19 patients receiving ECMO.The source of heterogeneity was investigated using subgroup and sensitivity analyses.RESULTS We identified 18 articles with 1494 COVID-19 patients who were receiving ECMO.The score of the quality assessment ranged from 5 to 8 on the NOS.The majority of patients received veno-venous ECMO(93.7%).Overall mortality was estimated to be 0.31[95%confidence interval(CI):0.24-0.39;I2=84.8%]based on random-effect pooled estimates.There were significant differences in mortality between location groups(33.0%vs 55.0%vs 37.0%vs 18.0%,P<0.001),setting groups(28.0%vs 34.0%,P<0.001),sample size(37.0%vs 31.0%,P<0.001),and NOS groups(39.0%vs 19.0%,P<0.001).However,both subgroup analyses based on location,setting,and sample size,and sensitivity analysis failed to identify the source of heterogeneity.The funnel plot indicated no evident asymmetry,and the Egger’s(P=0.95)and Begg’s(P=0.14)tests also revealed no significant publication bias.CONCLUSION With more resource assessment and risk-benefit analysis,our data reveal that ECMO might be a feasible and effective treatment for COVID-19 patients.

SUCCESSFUL EXTRACORPOREAL MEMBRANE OXYGENATION SUPPORT IN A PATIENT WITH FULMINANT MYOCARDITIS

FULMINANT myocarditis complicated with refractory cardiogenic shock carries a very high mortality （76%）. Herein we report our experi-ence in treating a 23-year-old Chinese woman with fulminant myocarditis complicated with cardiogenic shock, who was rescued by extracorporeal membrane oxygenation （ECMO）.

Combined use of extracorporeal membrane oxygenation with interventional surgery for acute pancreatitis with pulmonary embolism: A case report

BACKGROUND Acute pancreatitis(AP) is an acute inflammatory process of the pancreas characterized by self-digestion of pancreatic tissue, which can trigger a systemic inflammatory response. Venous thrombosis, resulting from a hypercoagulable state, is a vascular complication of AP. AP complicated by pulmonary embolism(PE) is very rare, and the combined use of extracorporeal membrane oxygenation(ECMO) with a vascular interventional procedure for AP complicated by PE is even rarer.CASE SUMMARY A 32-year-old man with a history of obesity developed rapidly worsening AP secondary to hypertriglyceridemia. During treatment, the patient developed chest tightness, shortness of breath, and cardiac arrest. Computed tomography(CT) scans of his upper abdomen were consistent with pancreatitis. PE was identified by chest CT angiography involving the right main pulmonary artery and multiple lobar pulmonary arteries. The patient’s D-dime level was significantly elevated(> 20 mg/L). The patient received high-frequency oxygen inhalation, continuous renal replacement therapies, anti-infective therapy, inhibition of pancreatic secretion, emergent endotracheal intubation, and advanced cardiac life support with cardiopulmonary resuscitation. Following both ECMO and a vascular interventional procedure, the patient recovered and was discharged.CONCLUSION PE is a rare but potentially lethal complication of AP. The early diagnosis of PE is important because an accurate diagnosis and timely interventional procedures can reduce mortality. The combined use of ECMO with a vascular interventional procedure for AP complicated by PE can be considered a feasible treatment method. A collaborative effort between multiple teams is also vital.

Successful kidney transplantation from an expanded criteria donor with long-term extracorporeal membrane oxygenation treatment: A case report

BACKGROUND Due to a shortage of donor kidneys, many centers have utilized graft kidneys from brain-dead donors with expanded criteria. Kidney transplantation(KT)from donors on extracorporeal membrane oxygenation(ECMO) has been identified as a successful way of expanding donor pools. However, there are currently no guidelines or recommendations that guarantee successful KT from donors undergoing ECMO treatment. Therefore, acceptance of appropriate allografts from those donors is solely based on clinician decision.CASE SUMMARY We report a case of successful KT from a brain-dead donor supported by ECMO for the longest duration to date. A 69-year-old male received a KT from a 63-yearold brain-dead donor who had been on therapeutic ECMO treatment for the previous three weeks. The recipient experienced slow recovery of graft function after surgery but was discharged home on post-operative day 17 free from hemodialysis. Allograft function gradually improved thereafter and was comparatively acceptable up to the 12 mo follow-up, with serum creatinine level of 1.67 mg/d L.CONCLUSION This case suggests that donation even after long-term ECMO treatment could provide successful KT to suitable candidates.