Venoarterial Extracorporeal Membrane Oxygenation Research Articles

Extracorporeal cardiopulmonary resuscitation-An orientation

Both in-hospital and out-of-hospital cardiac arrests are associated with ahigh mortality. In the past survival advantages for patients could be achieved by optimizing the chain of rescue and postresuscitation treatment; however, for patients with refractory cardiac arrest, there have so far been few promising treatment options. For selected patients with refractory cardiac arrest who do not achieve return of spontaneous circulation with conventional cardiopulmonary resuscitation (CPR), extracorporeal (e)CPR using venoarterial extracorporeal membrane oxygenation is an option to improve the probability of survival. This article describes the technical features, important aspects of treatment, and the current data situation on eCPR in patients with in-hospital or out-of-hospital cardiac arrest.

In patients supported with peripheral veno-arterial extracorporeal membrane oxygenation, what factors are associated with the development of spinal cord ischaemia?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'in patients supported with peripheral veno-arterial extracorporeal membrane oxygenation, what factors are associated with the development of spinal cord ischaemia'? Altogether, more than 22 papers were found using the reported search, of which 10 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Of the 28 patients reported by included studies, the thoracic spinal cord was most commonly affected. Twenty patients (71%) survived to hospital discharge and 7 (25%) were reported to have neurological recovery. Potential confounders included coronary angiography, cardiac arrest requiring chest compressions and concomitant intra-aortic balloon pump. Consequently, all papers highlighted the likely multifactorial aetiology of spinal cord infarction in these patients. We propose that close neurological observation, particularly in patients who have received chest compressions, and management of potential aetiological factors is crucial to aid in timely diagnosis and potential prevention of this rare complication. Limiting sedation and neuromuscular blockade to enable neurologic assessment of the lower limbs may allow more timely diagnosis.

Impact of extracorporeal membrane oxygenation-related complications on in-hospital mortality.

Although extracorporeal membrane oxygenation (ECMO) is a well-established treatment for supporting severe cardiopulmonary failure, the morbidity and mortality of patients requiring ECMO support remain high. Evaluating and correcting potential risk factors associated with any ECMO-related complications may improve care and decrease mortality. This study aimed to assess the predictors of ECMO-related vascular and cerebrovascular complications among adult patients and to test the hypothesis that ECMO-related complications are associated with higher in-hospital mortality rates. This single-center, retrospective study included 856 ECMO runs administered via cannulation of the femoral vessels of 769 patients: venoarterial (VA) ECMO (n = 709, 82.8%) and venovenous (VV) ECMO (n = 147, 17.2%). The study outcomes included the occurrence of ECMO-related vascular and cerebrovascular complications and in-hospital death. The association of ECMO-related complications with the risk of in-hospital death was analyzed. The incidences of ECMO-related vascular and cerebrovascular complications were 20.2% and 13.6%, respectively. The overall in-hospital mortality rate was 48.7%: 52.8% among VA ECMO runs and 29.3% among VV ECMO runs. Multivariable analysis indicated that age (P < 0.01), cardiopulmonary cerebral resuscitation (P < 0.01), continuous renal replacement therapy (P < 0.01), and initial platelet count [<50×103/μL (P = 0.02) and 50-100(×103)/μL (P < 0.01)] were associated with an increased risk of in-hospital death. ECMO-related vascular and cerebrovascular complications were not independently associated with higher in-hospital mortality rates for VA or VV ECMO runs. ECMO-related vascular and cerebrovascular complications were not associated with an increased risk of in-hospital death among adult patients.

End-stage renal disease should not Be considered a contraindication for veno-arterial extracorporeal membrane oxygenation

BackgroundThis study aims to determine whether end-stage renal disease (ESRD) is a true contraindication for extracorporeal membrane oxygenation in adult patients. Materials and methodsAdult patients who received VA-ECMO at National Taiwan University Hospital between January 2010 and December 2021 were included. Patients who received regular dialysis before the index admission were included in the ESRD group. The primary outcome was in-hospital mortality. Results1341 patients were included in the analysis, 121 of whom had ESRD before index admission. The ESRD group was older (62.3 versus 56.8 years; P < 0.01) and had more comorbidities. Extracorporeal cardiopulmonary resuscitation (ECPR) was used more frequently in the ESRD group (66.1% versus 51.6%; P < 0.001). The ESRD group had higher in-hospital mortality rates (72.7% versus 63.3%; P = 0.03). In the ECPR subgroup, there was no difference of survival between ESRD and others(P = 0.56). In the multivariate Cox regression, ESRD was not an independent predictor for mortality (P = 0.20). ConclusionESRD was not an independent predictor of in-hospital mortality after VA-ECMO. The survival of ESRD patients was not inferior to those without ESRD when receiving ECPR. Therefore, ESRD should not be considered a contraindication to VA-ECMO in adults.

Comparison of Mixed Venous Oxygen Saturation and Premembranous Venous Oxygen Saturation in Patients on Peripheral Venous-Arterial Extracorporeal Membrane Oxygenation.

In patients on veno-arterial extracorporeal membrane oxygenation (ECMO) premembranous venous oxygen saturation (Spm-vO2) is continuously displayed on the ECMO console. However, the concordance between Spm-vO2 and mixed venous oxygen saturation (SvO2) remains largely unexplored. Our single-center retrospective study included adult patients who had paired SvO2 and Spm-vO2 readings within 15 minutes of each other, on peripherally cannulated Vf ivc-A ECMO and a pulmonary artery using catheter (PAC). The 82 pairs of observations showed a mean difference of 11.37% (95% limits of agreement -6.0 to 28.74, p < 0.001) between Spm-vO2 and SvO2. Although the two values correlated with each other (r = 0.51, p < 0.01), the difference between the paired measurements was larger at lower values of SvO2 (3.72 ± 6.38% when SvO2 >80%, 11.79±7.46% when SvO2 between 60% and 80%, and 18.81±12.09% when SvO2 <60%). The equation SvO2 = 1.2* Spm-vO2 - 28.03 was obtained by Passing Bablok regression. Cardiac index calculated by Spm-vO2 and SvO2 differed by 0.8L/minute/m2 (95% limits of agreement -0.52 to 2.17, p < 0.001). In peripheral VA-ECMO, Spm-vO2 is consistently higher than SvO2, with more discordance at lower saturation levels. Using Spm-vO2 to estimate cardiac output using Fick method yields inaccurate results.

Mortality in patients with normal left ventricular function requiring emergency VA-ECMO for postcardiotomy cardiogenic shock due to coronary malperfusion.

To analyze outcomes in patients with normal preoperative left ventricular ejection fraction (LVEF) undergoing venoarterial extracorporeal membrane oxygenation (VA-ECMO) therapy due to postcardiotomy cardiogenic shock (PCCS) related to coronary malperfusion. Retrospective single-center analysis in patients with normal preoperative LVEF treated with VA-ECMO for coronary malperfusion-related PCCS between May 1998 and May 2018. The primary outcome was 30-day mortality, which was compared using the Kaplan-Meier method and the log-rank test. Multivariable logistic regression was performed to identify predictors of mortality. During the study period, a total of 62,125 patients underwent cardiac surgery at our institution. Amongst them, 59 patients (0.1%) with normal preoperative LVEF required VA-ECMO support due to coronary malperfusion-related PCCS. The mean duration of VA-ECMO support was 6 days (interquartile range 4-7 days). The 30-day mortality was 50.8%. Under VA-ECMO therapy, a complication composite outcome of bleeding, re-exploration for bleeding, acute renal failure, acute liver failure, and sepsis occurred in 51 (86.4%) patients. Independent predictors of 30-day mortality were lactate levels > 9.9 mmol/l before VA-ECMO implantation (odds ratio [OR]: 3.3; 95% confidence interval [CI] 1.5-7.0; p = 0.002), delay until revascularization > 278 minutes (OR: 2.9; 95% CI 1.3-6.4; p = 0.008) and peripheral arterial artery disease (OR: 3.3; 95% 1.6-7.5; p = 0.001). Mortality rates are high in patients with normal preoperative LVEF who develop PCCS due to coronary malperfusion. The early implantation of VA-ECMO before the development of profound tissue hypoxia and early coronary revascularization increases the likelihood of survival. Lactate levels are useful to define optimal timing for the VA-ECMO initiation.

Comparison of percutaneous decannulation and open surgical repair for large-bore arterial access sites of extracorporeal membrane oxygenation.

Following weaning of peripheral venoarterial extracorporeal membrane oxygenation (ECMO) support, removal of cannulas and repair of large-bore arterial sites is traditionally by open surgical repair (OSR). The use of a percutaneous vascular closure device (VCD) offers a minimally invasive alternative to OSR with potential for reduced operative complications, reduced hospital length of stay and in-hospital mortality. A systematic review of Medline and Embase databases was conducted for studies comparing VCD-assisted decannulation with OSR following decannulation of peripheral ECMO. The primary endpoint was rate of post-procedural complications, namely wound infection and limb ischaemia. The secondary endpoint was in-hospital mortality. Eight studies, with a total of 685 patients, met inclusion criteria. Forty-eight percent (n = 328) of patients underwent VCD-assisted decannulation with the remainder decannulated by OSR. Pooled analysis demonstrated that patients undergoing VCD-assisted decannulation are at significantly lower risk of overall complications than surgical repair (OR 4.34; 95% CI 2.19-8.57; p < .001). Specifically, there was a substantial decrease in groin infections (OR 6.77; 95% CI 3.07-14.97; p < .001) without notable differences in limb ischaemia or pseudoaneurysm occurrence between the VCD and OSR cohorts. There was a lower incidence of intra-operative bleeding and haematoma in the VCD cohort (p < .001 and p = .002, respectively). Vascular closure device-assisted decannulation of peripheral ECMO offers a significantly reduced risk of complications, particularly groin infections and bleeding. Future research should encompass larger cohorts, randomised controlled trials, cost-benefit analyses, and the training of surgeons, cardiologists and intensivists in VCD-assisted decannulation, potentially through the integration of simulation-based training.

Fibrinolysis as a Causative Mechanism for Bleeding Complications on Extracorporeal Membrane Oxygenation: A Pilot Observational Prospective Study.

Extracorporeal membrane oxygenation (ECMO) is associated with a high risk of bleeding complications. The specific impact of ECMO on fibrinolysis remains unexplored. The objective of the current pilot observational prospective study was to investigate the longitudinal dynamics of fibrinolytic markers-i.e., changes over time-in the context of bleeding events in patients on ECMO. Longitudinal dynamics of contact phase components (kininogen and bradykinin) and fibrinolysis markers (tissue plasminogen activator [tPA], plasminogen activator inhibitor-1 [PAI-1], their complexes [tPA•PAI-1], plasmin-antiplasmin complexes, plasminogen, and D-dimer) were measured in patients undergoing venovenous and venoarterial ECMO, before implantation, at 0, 6, and 12 h after implantation, and daily thereafter. The cohort consisted of 30 patients (214 ECMO days). The concentrations of tPA, D-dimer, plasmin-antiplasmin complexes, PAI-1, and tPA•PAI-1 complexes were increased, whereas plasminogen decreased compared to normal values. A noteworthy divergence was observed between hemorrhagic and nonhemorrhagic patients: in bleeding patients, D-dimer, plasmin-antiplasmin, tPA, PAI-1, and tPA•PAI-1 followed an increasing kinetics before hemorrhage and then decreased to their baseline level; conversely, nonbleeding patients showed a decreasing kinetics in these markers. Also, D-dimer and tPA followed an increasing kinetics in bleeding patients compared to nonbleeding patients (median values for D-dimer dynamics: 1,080 vs. -440 ng/ml, P = 0.05; tPA dynamics: 0.130 vs. 0.100 nM, P = 0.038), and both markers significantly increased the day before hemorrhage. A tPA concentration above 0.304 nM was associated with bleeding events (odds ratio, 4.92; 95% CI, 1.01 to 24.08; P = 0.049). Contact activation induces fibrinolysis in ECMO patients, especially in patients experiencing bleeding. This finding supports the role of this mechanism as a possible causal factor for hemorrhages during ECMO and open new avenues for novel therapeutic perspectives.

Early vs. delayed mechanical circulatory support in patients with acute myocardial infarction and cardiogenic shock.

Despite increased temporary mechanical circulatory support (tMCS) utilization for acute myocardial infarction complicated by cardiogenic shock (AMI-CS), data regarding efficacy and optimal timing for tMCS support are limited. This study aimed to describe outcomes based on tMCS timing in AMI-CS and to identify predictors of 30-day mortality and readmission. Patients with AMI-CS identified in the National Readmissions Database were grouped according to the use of tMCS and early (<24 h) vs. delayed (≥24 h) tMCS. The correlation between tMCS timing and inpatient outcomes was evaluated using linear regression. Multivariate logistic regression was used to identify variables associated with 30-day mortality and readmission. Of 294 839 patients with AMI-CS, 109 148 patients were supported with tMCS (8067 veno-arterial extracorporeal membrane oxygenation, 33 577 Impella, and 79 161 intra-aortic balloon pump). Of patients requiring tMCS, patients who received early tMCS (n = 79 906) had shorter lengths of stay (7 vs. 15 days, P < 0.001) and lower rates of ischaemic and bleeding complications than those with delayed tMCS (n = 32 241). Patients requiring tMCS had higher in-hospital mortality [odds ratio (95% confidence interval)] [1.7 (1.7-1.8), P < 0.001]. Among patients requiring tMCS, early support was associated with fewer complications, lower mortality [0.90 (0.85-0.94), P < 0.001], and fewer 30-day readmissions [0.91 (0.85-0.97), P = 0.005] compared with patients with delayed tMCS. Among patients receiving tMCS for AMI-CS, early tMCS was associated with fewer complications, shorter lengths of stay, lower hospital costs, and fewer deaths and readmissions at 30 days.

A Survey to Quantify the Number and Structure of Extracorporeal Membrane Oxygenation Retrieval Programs in the United States.

(1) Background: Extracorporeal membrane oxygenation (ECMO) represents a potentially lifesaving support for respiratory and/or circulatory failure but its availability is limited to larger medical centers. A well-organized regional ECMO center with remote cannulation and retrieval ability can offer this intervention to patients treated at hospitals without ECMO. Information regarding the number and structure of ECMO retrieval programs in the United States is limited and there are no data regarding the size and structure of existing programs and which physician specialists perform cannulations and provide management. (2) Methods: We created a survey of 12 questions that was sent out to all adult US ECMO programs registered in the ELSO database. The data for the study were collected through an online survey instrument that was developed in Survey Monkey (Monkey Headquarters, Portland, OR). (3) Results: Approximately half of the centers that received the survey responded: 136 out of 274 (49.6%). Sixty-three centers (46%) have an ECMO retrieval program; 58 of these offer both veno-arterial (V-A) and veno-venous (V-V) ECMO, while 5 programs offer V-V ECMO rescue only. Thirty-three (52%) centers perform less than 10 ECMO retrievals per year, and only five (8%) hospitals can perform more than 50 ECMO rescues per year. Cardiothoracic surgeons perform the majority of the ECMO cannulations during retrievals in 30 programs (48%), followed by intensivists in eight (13%) programs and cardiologists in three (5%) centers. (4) Conclusions: Many ECMO centers offer ECMO retrievals; however, only a minority of the programs perform a large number of rescues per year. These cannulations are primarily performed by cardiothoracic surgeons.

Temporary extracorporeal life support: single-centre experience with a new concept.

The combination of veno-arterial extracorporeal membrane oxygenation with a micro-axial flow pump (ECMELLA) is increasingly used for cardiogenic shock (CS) therapy. We report our experience with a novel single-artery access ECMELLA setup with either femoral (2.0) or jugular venous cannulation (2.1), respectively. Data from 67 consecutive CS patients treated with ECMELLA 2.0 (n = 56) and 2.1 (n = 11) from December 2020 and December 2022 in a tertiary cardiac center were retrospectively analyzed. The mean age was 60.7 ± 11 years, 56 patients (84%) were male. CS aetiology was acute on chronic heart failure (n = 35, 52%), myocardial infarction (n = 13, 19.5%), postcardiotomy syndrome (n = 16, 24%) and myocarditis (n = 3, 4.5%). Preoperatively 31 patients (46%) were resuscitated, 53 (79%) were on a ventilator and 60 (90%) were on inotropic support. The median vasoactive inotropic score was 32, and the mean arterial lactate was 8.1 mmol/l. In 39 patients (58%), veno-arterial extracorporeal membrane oxygenation was explanted after a median ECMELLA support of 4 days. Myocardial recovery was achieved in 18 patients (27%), transition to a durable left ventricular assist device in 16 (24%). Thirty-three patients (n = 33; 49%) died on support (25 on ECMELLA and 8 on Impella after de-escalation), 9 (13%) of whom were palliated. Axillary access site bleeding occurred in 9 patients (13.5%), upper limb ischaemia requiring surgical revision in 3 (4.5%). Axillary site infection occurred in 6 cases (9%), and perioperative stroke in 10 (15%; 6 hemorrhagic, 4 thromboembolic). ECMELLA 2.0/2.1 is a feasible and effective therapy for severe CS. The single-artery cannulation technique is associated with a relatively low rate of access-related complications.

Impella 5.5 Bridge to Heart Transplant: An Institutional Series and a Closer Look at Device Removal Technique.

Limited donor organ availability often necessitates mechanical circulatory support, and recently the Impella 5.5, as a bridge to heart transplant. Of 175 Impella 5.5-supported patients at our institution, 45 underwent transplantation in the largest series to date, for whom we analyzed outcomes. Two methods of complete device explant were evaluated: central Impella transection and removal via axillary graft. Median Impella days were 25 (16-41); median waitlist days were 21 (9-37). Eighty-nine percent (40/45) of patients had device placement via right axillary artery. Seventy-six percent (34/45) underwent central transection for device removal. Four patients (8.9%) required short-term venoarterial extracorporeal membranous oxygenation (VA ECMO) postoperatively for primary graft dysfunction (PGD). Two patients (4.4%) suffered postoperative stroke. Five patients (11.1%) required new RRT postoperatively. One patient (2.2%) returned to the operating room (OR) for axillary graft bleeding. A higher chance of procedural complications was found with the axillary removal technique ( p = 0.014). Median intensive care unit (ICU) days, length of stay (LOS), and postoperative days to discharge were 46 (35-63), 59 (49-80), and 18 (15-24), respectively. Ninety-eight percent (44/45) survived to discharge. Thirty-day survival was 95.6% (43/45), with 1 year survival at 90.3% (28/31). Eighty-eight percent (37/42) remain without rejection. In our institutional experience, Impella 5.5 is a safe and reliable bridge to transplant.

Switching from VA-ECMO to a Percutaneous right Ventricular assist device as a Bridge to Recovery in a Case of right Ventricular Myocardial Infarction

Acute right heart failure (RHF) is associated with high morbidity and mortality. Temporary mechanical circulatory support (MCS) is now part of the advanced management strategy for refractory cardiogenic shock (CS). Among such support systems, veno-arterial Extracorporeal Membrane Oxygenation (VA-ECMO) remains the fastest MCS system to set up. The ProtekDuo cannula can be used as a temporary and percutaneous right ventricular assist device (RVAD) in relay with VA-ECMO in the context of prolonged weaning. This case report describes the clinical course of a 69-year-old patient who underwent elective aortic valve replacement surgery complicated by acute RHF due to iatrogenic ligation of the right coronary artery. VA-ECMO was initiated in the context of refractory cardiogenic shock. Faced with prolonged MCS weaning, due to lack of recovery of the right ventricle associated with the absence of any other therapeutic option, a percutaneous RVAD via a ProtekDuo cannula was implanted as a bridge to recovery. The ProtekDuo was gradually weaned while the patient began rehabilitation. The patient was transferred to the medical ward after 5 weeks in the ICU, stayed 5 months in an acute medical setting, went to a rehabilitation center afterward and returned home 6 months after the initial surgery without any neurological sequalae or organ failures. In total, she remained on MCS for 39 days (21 on VA-ECMO and 18 on ProtekDuo). In cases of refractory RHF, after stabilization and organ perfusion restoration under VA-ECMO, it is feasible to switch to a percutaneous RVAD, allowing early mobilization of patients during prolonged MCS weaning until the right ventricle adapts to new loading conditions.

Differences in Treatment Outcomes According to the Insertion Method Used in Extracorporeal Cardiopulmonary Resuscitation: A Single-Center Experience.

Venoarterial extracorporeal membrane oxygenation (ECMO) is a key treatment method used with patients in cardiac arrest who do not respond to medical treatment. A critical step in initiating therapy is the insertion of ECMO cannulas. Peripheral ECMO cannulation methods have been preferred for extracorporeal cardiopulmonary resuscitation (ECPR). Patients who underwent ECPR at Daegu Catholic University Medical Center between January 2017 and May 2023 were included in this study. We analyzed the impact of 2 different peripheral cannulation strategies (surgical cutdown vs. percutaneous cannulation) on various factors, including survival rate. Among the 99 patients included in this study, 66 underwent surgical cutdown, and 33 underwent percutaneous insertion. The survival to discharge rates were 36.4% for the surgical cutdown group and 30.3% for the percutaneous group (p=0.708). The ECMO insertion times were 21.3 minutes for the surgical cutdown group and 10.3 minutes for the percutaneous group (p<0.001). The factors associated with overall mortality included a shorter low-flow time (hazard ratio [HR], 1.045; 95% confidence interval [CI], 1.019-1.071; p=0.001) and whether return of spontaneous circulation was achieved (HR, 0.317; 95% CI, 0.127-0.787; p=0.013). Low-flow time was defined as the time from the start of cardiopulmonary resuscitation to the completion of ECMO cannula insertion. No statistically significant difference in in-hospital mortality was observed between the surgical and percutaneous groups. However, regardless of the chosen cannulation strategy, reducing ECMO cannulation time was beneficial, as a shorter low-flow time was associated with significant benefits in terms of survival.

Bleeding complications, coagulation disorders, and their management in acute myocardial infarction-related cardiogenic shock rescued by veno-arterial ECMO: A retrospective cohort study

PurposeManagement of dual antiplatelet therapy (DAPT) in patients on venoarterial-extracorporeal membrane (VA-ECMO) after acute myocardial infarction (AMI) is challenging. Our objective was to describe the frequency, management and outcomes of severe bleeding complications and determine their occurrence risk factors. Material and methodsWe conducted a retrospective observational cohort study including post-AMI cardiogenic shock patients requiring VA-ECMO. Severe bleeding was defined based on the Bleeding Academic Research Consortium classification. We calculated multivariable Fine–Gray models to assess factors associated with risk of severe bleeding. ResultsFrom January 2015 to July 2019, 176 patients received VA-ECMO after AMI and 132 patients were included. Sixty-five (49%) patients died. Severe bleeding occurred in 39% of cases. Severe thrombocytopenia (< 50 G/L) and hypofibrinogenemia (<1,5 g/L) occurred in respectively 31% and 19% of patients. DAPT was stopped in 32% of patients with a 6% rate of stent thrombosis. Anticoagulation was stopped in 39% of patients. Using a multivariate competing risk model, female sex, time on ECMO, troponin at admission and Impella® implantation were independently associated with severe bleeding. ConclusionsBleeding complications and coagulation disorders were frequent and severe in patients on VA-ECMO after AMI, leading of antiplatelet therapy withdrawal in one third of patients.

Blood flow and emboli transport patterns during venoarterial extracorporeal membrane oxygenation: A computational fluid dynamics study

ProblemDespite advances in Venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO), a significant mortality rate persists due to complications. The non-physiological blood flow dynamics of VA-ECMO may lead to neurological complications and organ ischemia. Continuous retrograde high-flow oxygenated blood enters through a return cannula placed in the femoral artery which opposes the pulsatile deoxygenated blood ejected by the left ventricle (LV), which impacts upper body oxygenation and subsequent hyperoxemia. The complications underscore the critical need to comprehend the impact of VA-ECMO support level and return cannula size, as mortality remains a significant concern. AimThe aim of this study is to predict and provide insights into the complications associated with VA-ECMO using computational fluid dynamics (CFD) simulations. These complications will be assessed by characterising blood flow and emboli transport patterns through a comprehensive analysis of the influence of VA-ECMO support levels and arterial return cannula sizes. MethodsPatient-specific 3D aortic and major branch models, derived from a male patient's CT scan during VA-ECMO undergoing respiratory dysfunction, were analyzed using CFD. The investigation employed species transport and discrete particle tracking models to study ECMO blood (oxygenated) mixing with LV blood (deoxygenated) and to trace emboli transport patterns from potential sources (circuit, LV, and aorta wall). Two cannula sizes (15 Fr and 19 Fr) were tested alongside varying ECMO pump flow rates (50%, 70%, and 90% of the total cardiac output). ResultsCannula size did not significantly affect oxygen transport. At 90% VA-ECMO support, all arteries distal to the aortic arch achieved 100% oxygen saturation. As support level decreased, oxygen transport to the upper body also decreased to a minimum saturation of 73%. Emboli transport varied substantially between emboli origin and VAECMO support level, with the highest risk of cerebral emboli coming from the LV with a 15 Fr cannula at 90% support. ConclusionArterial return cannula sizing minimally impacted blood oxygen distribution; however, it did influence the distribution of emboli released from the circuit and aortic wall. Notably, it was the support level alone that significantly affected the mixing zone of VA-ECMO and cardiac blood, subsequently influencing the risk of embolization of the cardiogenic source and oxygenation levels across various arterial branches.

Capillary refill time assessment after fluid challenge in patients on venoarterial extracorporeal membrane oxygenation: A retrospective study

BackgroundMonitoring fluid therapy is challenging in patients assisted with Veno-arterial ECMO. The aim of our study was to evaluate the usefulness of capillary refill time to assess the response to fluid challenge in patients assisted with VA-ECMO. MethodsRetrospective monocentric study in a cardiac surgery ICU. We assess fluid responsiveness after a fluid challenge in patients on VA-ECMO. We recorded capillary refill time before and after fluid challenge and the evolution of global hemodynamic parameters. ResultsA total of 27 patients were included. The main indications for VA-ECMO were post-cardiotomy cardiogenic shock (44%). Thirteen patients (42%) were responders and 14 non-responders (58%). In the responder group, the index CRT decreased significantly (1.7 [1.5; 2.1] vs. 1.2 [1; 1.3] s; p = 0.01), whereas it remained stable in the non-responder group (1.4 [1.1; 2.5] vs. 1.6 [0.9; 1.9] s; p = 0.22). Diagnosis performance of CRT variation to assess response after fluid challenge shows an AUC of 0.68 (p = 0.10) with a sensitivity of 79% [95% CI, 52–92] and a specificity of 69% [95% CI, 42–87], with a threshold at 23%. ConclusionIn patients treated with VA-ECMO index capillary refill time is a reliable tool to assesses fluid responsiveness. SpecialtyCritical care, Cardiac surgery, ECMO.

External validation of the PC-ECMO score in postcardiotomy veno-arterial extracorporeal membrane oxygenation.

Reliable stratification of the risk of early mortality after postcardiotomy veno-arterial extracorporeal membrane oxygenation (V-A-ECMO) remains elusive. In this study, we externally validated the PC-ECMO score, a specific risk scoring method for prediction of in-hospital mortality after postcardiotomy V-A-ECMO. Overall, 614 patients who required V-A-ECMO after adult cardiac surgery were gathered from an individual patient data meta-analysis of nine studies on this topic. The AUC of the logistic PC-ECMO score in predicting in-hospital mortality was 0.678 (95%CI 0.630-0.726; p < 0.0001). The AUC of the logistic PC-ECMO score in predicting on V-A-ECMO mortality was 0.652 (95%CI 0.609-0.695; p < 0.0001). The Brier score of the logistic PC-ECMO score for in-hospital mortality was 0.193, the slope 0.909, the calibration-in-the-large 0.074 and the expected/observed mortality ratio 0.979. 95%CIs of the calibration belt of fit relationship between observed and predicted in-hospital mortality were never above or below the bisector (p = 0.072). The present findings suggest that the PC-ECMO score may be a valuable tool in clinical research for stratification of the risk of patients requiring postcardiotomy V-A-ECMO.

Diaphragm thickness modifications and associated factors during VA-ECMO for a cardiogenic shock: a cohort study

BackgroundThe incidence, causes and impact of diaphragm thickness evolution in veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock are unknown.Our study investigates its evolution during the first week of VA-ECMO and its relationship with sweep gas flow settings.MethodsWe conducted a prospective monocentric observational study in a 12-bed ICU in France, enrolling patients on the day of the VA-ECMO implantation. The diaphragm thickness and the diaphragm thickening fraction (as index of contractile activity, dTF; dTF < 20% defined a low contractile activity) were daily measured for one week using ultrasound. Factors associated with diaphragm thickness evolution (categorized as increased, stable, or atrophic based on > 10% modification from baseline to the last measurement), early extubation role (< day4), and patients outcome at 60 days were investigated. Changes in diaphragm thickness, the primary endpoint, was analysed using a mixed-effect linear model (MLM).ResultsOf the 29 included patients, seven (23%) presented diaphragm atrophy, 18 remained stable (60%) and 4 exhibited an increase (17%). None of the 13 early-extubated patients experienced diaphragm atrophy, while 7 (46%) presented a decrease when extubated later (p-value = 0.008). Diaphragm thickness changes were not associated with the dTF (p-value = 0.13) but with sweep gas flow (Beta = − 3; Confidence Interval at 95% (CI) [− 4.8; − 1.2]. p-value = 0.001) and pH (Beta = − 2; CI [− 2.9; − 1]. p-value < 0.001) in MLM. The dTF remained low (< 20%) in 20 patients (69%) at the study’s end and was associated with sweep gas flow evolution in MLM (Beta = − 2.8; 95% CI [− 5.2; − 0.5], p-value = 0.017). Odds ratio of death at 60 days in case of diaphragm atrophy by day 7 was 8.50 ([1.4–74], p = 0.029).ConclusionIn our study, diaphragm thickness evolution was frequent and not associated with the diaphragm thickening fraction. Diaphragm was preserved from atrophy in case of early extubation with ongoing VA-ECMO assistance. Metabolic disorders resulting from organ failures and sweep gas flow were linked with diaphragm thickness evolution. Preserved diaphragm thickness in VA-ECMO survivors emphasizes the importance of diaphragm-protective strategies, including meticulous sweep gas flow titration.

Early outcomes of moderate-to-high-risk pediatric congenital cardiac surgery and predictors of extracorporeal circulatory life support requirement.

Cardiopulmonary failure refractory to medical management after moderate-to-high-risk congenital cardiac surgery may necessitate mechanical support with veno-arterial extracorporeal membrane oxygenation (ECMO). On the extreme, ECMO can also be initiated in the setting of cardiac arrest (extracorporeal cardiopulmonary resuscitation, ECPR) unresponsive to conventional resuscitative measures. This was a single-center retrospective cohort study of patients (n = 510) aged <3 years old who underwent cardiac surgery with cardiopulmonary bypass with a RACHS-1 score ≥3 between 2011 and 2014. Perioperative factors were reviewed to identify predictors of ECMO initiation and mortality in the operating room (OR) and the intensive care unit (ICU). A total of 510 patients with a mean surgical age of 10.0 ± 13.4 months were included. Among them, 21 (4%) patients received postoperative ECMO-12 were initiated in the OR and 9 in the ICU. ECMO cannulation was associated with cardiopulmonary bypass duration, aortopulmonary shunt, residual severe mitral regurgitation, vaso-inotropic score, and postprocedural lactate (p < 0.001). Of the 32 (6%) total deaths, 7 (22%) were ECMO patients-4 were elective OR cannulations and 3 were ICU ECPR. Prematurity [hazard ratio (HR): 2.61, p < 0.01), Norwood or Damus-Kaye-Stansel procedure (HR: 4.29, p < 0.001), postoperative left ventricular dysfunction (HR: 5.10, p = 0.01), residual severe tricuspid regurgitation (HR: 6.06, p < 0.001), and postoperative ECMO (ECPR: HR: 15.42, p < 0.001 vs. elective: HR: 5.26, p = 0.01) were associated with mortality. The two patients who were electively cannulated in the ICU survived. Although uncommon, postoperative ECMO in children after congenital cardiac surgery is associated with high mortality, especially in cases of ECPR. Patients with long cardiopulmonary bypass time, residual cardiac lesions, or increased vaso-inotropic requirement are at higher risk of receiving ECMO. Pre-emptive or early ECMO initiation before deterioration into cardiac arrest may improve survival.