Four decades of experience of prosthetic valve endocarditis reflect a high variety of diverse pathogens.

Prosthetic valve endocarditis (PVE) remains a serious condition with a high mortality rate. Precise identification of the PVE-associated pathogen/s and their virulence is essential for successful therapy and patient survival. The commonly described PVE-associated pathogens are staphylococci, streptococci, and enterococci, with Staphylococcus aureus being the most frequently diagnosed species. Furthermore, multi-drug resistance pathogens are increasing in prevalence and continue to pose new challenges mandating a personalized approach. Blood cultures in combination with echocardiography are the most common methods to diagnose PVE, often being the only indication, it exists. In many cases, the diagnostic strategy recommended in the clinical guidelines does not identify the precise microbial agent, and frequently, false-negative blood cultures are reported. Despite the fact that blood culture findings are not always a good indicator of the actual PVE agent in the valve tissue, only a minority of re-operated prostheses are subjected to microbiological diagnostic evaluation. In this review, we focus on the diversity and the complete spectrum of PVE-associated bacterial, fungal, and viral pathogens in blood and prosthetic heart valve, their possible virulence potential, and their challenges in making a microbial diagnosis. We are curious to understand if the unacceptable high mortality of PVE is associated with the high number of negative microbial findings in connection with a possible PVE. Herein, we discuss the possibilities and limits of the diagnostic methods conventionally used and make recommendations for enhanced pathogen identification. We also show possible virulence factors of the most common PVE-associated pathogens and their clinical effects. Based on blood culture, molecular biological diagnostics, and specific valve examination, better derivations for the antibiotic therapy as well as possible preventive intervention can be established in the future.

Venting during venoarterial extracorporeal membrane oxygenation.

Cardiogenic shock and cardiac arrest contribute pre-dominantly to mortality in acute cardiovascular care. Here, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has emerged as an established therapeutic option for patients suffering from these life-threatening entities. VA-ECMO provides temporary circulatory support until causative treatments are effective and enables recovery or serves as a bridging strategy to surgical ventricular assist devices, heart transplantation or decision-making. However, in-hospital mortality rate in this treatment population is still around 60%. In the recently published ARREST trial, VA-ECMO treatment lowered mortality rate in patients with ongoing cardiac arrest due to therapy refractory ventricular fibrillation compared to standard advanced cardiac life support in selected patients. Whether VA-ECMO can reduce mortality compared to standard of care in cardiogenic shock has to be evaluated in the ongoing prospective randomized studies EURO-SHOCK (NCT03813134) and ECLS-SHOCK (NCT03637205). As an innate drawback of VA-ECMO treatment, the retrograde aortic flow could lead to an elevation of left ventricular (LV) afterload, increase in LV filling pressure, mitral regurgitation, and elevated left atrial pressure. This may compromise myocardial function and recovery, pulmonary hemodynamics-possibly with concomitant pulmonary congestion and even lung failure-and contribute to poor outcomes in a relevant proportion of treated patients. To overcome these detrimental effects, a multitude of venting strategies are currently engaged for both preventive and emergent unloading. This review aims to provide a comprehensive and structured synopsis of existing venting modalities and their specific hemodynamic characteristics. We discuss in detail the available data on outcome categories and complication rates related to the respective venting option.

Comparison of the CytoSorb® 300 mL and Jafron HA380 hemoadsorption devices: an in vitro study.

INTRODUCTION: We performed an analysis of two blood purification systems to determine their performance for removing interleukins (ILs)-6 and 10, tumor necrosis factor (TNF)-α and monocyte chemoattractant protein (MCP)-1 from blood. MATERIAL AND METHODS: An in vitro hemoperfusion blood recirculation circuit was used to compare the CytoSorb® 300 mL (CytoSorbents Inc., Princeton, NJ) and Jafron HA 380 (Jafron Biomedical Co., Ltd., Zhuhai City, China) devices. The removal of purified recombinant human IL-6, IL-10, TNFα and MCP-1 by the adsorbers was compared at various timepoints. Three runs were completed and removal was evaluated as the mean area under the curve (AUC). RESULTS: Both devices showed effective removal of the tested cytokines. IL-6, IL-10, TNFα and MCP-1 were removed faster and to a higher extent by the CytoSorb® 300 mL device. At maximal time of 12 h, overall removal according to AUC of remaining concentrations was significantly lower with CytoSorb® 300 mL compared with HA 380 (IL-6: 1075.5 ± 665.9 vs. 4345.1 ± 1499.3 (p = 0.01), IL-10: 5065.7 ± 882.5 vs. 11,939.7 ± 4523.1 (p = 0.03), TNF-α: 6519.9 ± 997.6 vs. 10,303.7 ± 2347.0 (p = 0.03) and MCP-1: 278.9 ± 40.7 vs. 607.3 ± 84.4 (p = 0.001)). CONCLUSIONS: Both the CytoSorb® and the Jafron HA 380 devices are capable of removing cytokines from blood in a benchtop model. The CytoSorb® 300 device was significantly more efficient achieving the bulk of the removal in the first 120 min.

Early Use of Methylene Blue in Vasoplegic Syndrome: A 10-Year Propensity Score-Matched Cohort Study.

BACKGROUND: Vasoplegic syndrome is associated with increased morbidity and mortality in patients undergoing cardiac surgery. This retrospective, single-center study aimed to evaluate the effect of early use of methylene blue (MB) on hemodynamics after an intraoperative diagnosis of vasoplegic syndrome (VS). METHODS: Over a 10-year period, all patients diagnosed with intraoperative VS (hypotension despite treatment with norepinephrine ≥0.3 µg/kg/min and vasopressin ≥1 IE/h) while undergoing heart surgery and cardiopulmonary bypass were identified, and their data were examined. The intervention group received MB (2 mg/kg intravenous) within 15 min after the diagnosis of vasoplegia, while the control group received standard therapy. The two groups were matched using propensity scores. RESULTS: Of the 1022 patients identified with VS, 221 received MB intraoperatively, and among them, 60 patients received MB within 15 min after the diagnosis of VS. After early MB application, mean arterial pressure was significantly higher, and vasopressor support was significantly lower within the first hour (p = 0.015) after the diagnosis of vasoplegia, resulting in a lower cumulative amount of norepinephrine (p = 0.018) and vasopressin (p = 0.003). The intraoperative need of fresh frozen plasma in the intervention group was lower compared to the control group (p = 0.015). Additionally, the intervention group had higher creatinine values in the first three postoperative days (p = 0.036) without changes in dialysis incidence. The 90-day survival did not differ significantly (p = 0.270). CONCLUSION: Our results indicate the additive effects of MB use during VS compared to standard vasopressor therapy only. Early MB administration for VS may significantly improve the patients' hemodynamics with minor side effects.

Case report: Heart Mate III for systemic right ventricular support in a patient with hypoplastic left heart syndrome.

Ventricular assist device implantation presents a possible bridge to heart transplantation for patients with failing Fontan physiology. However, evidence regarding outcome and possible pitfalls associated with the Fontan circulation is still insufficient. We describe the course of a 13-year-old male, who was born with hypoplastic left heart syndrome and underwent HeartMate III implantation due to refractory failure of the systemic right ventricle.

Extracorporeal life support in therapy-refractory cardiocirculatory failure: looking beyond 30 days.

OBJECTIVES: Venoarterial extracorporeal life support (ECLS) has emerged as a potentially life-saving treatment option in therapy-refractory cardiocirculatory failure, but longer-term outcome is poorly defined. Here, we present a comprehensive follow-up analysis covering all major organ systems. METHODS: From February 2012 to December 2016, 180 patients were treated with ECLS for therapy-refractory cardiogenic shock or cardiac arrest. The 30-day survival was 43.9%, and 30-day survivors (n = 79) underwent follow-up analysis with the assessment of medium-term survival, quality of life, neuropsychological, cardiopulmonary and end-organ status. RESULTS: After a median of 1.9 (1.1-3.6) years (182.4 patient years), 45 of the 79 patients (57.0%) were alive, 35.4% had died and 7.6% were lost to follow-up. Follow-up survival estimates were 78.0% at 1, 61.2% at 3 and 55.1% at 5 years. NYHA class at follow-up was ≤II for 83.3%. The median creatinine was 1.1 (1.0-1.4) mg/dl, and the median bilirubin was 0.8 (0.5-1.0) mg/dl. No patient required dialysis. Overall, 94.4% were free from moderate or severe disability, although 11.1% needed care. Full re-integration into social life was reported by 58.3%, and 39.4% were working. Quality of life was favourable for mental components, but a subset showed deficits in physical aspects. While age was the only peri-implantation parameter significantly predicting medium-term survival, adverse events and functional status at discharge or 30 days were strong predictors. CONCLUSIONS: This study demonstrates positive medium-term outcome with high rates of independence in daily life and self-care but a subset of 10-20% suffered from sustained impairments. Our results indicate that peri-implantation parameters lack predictive power but downstream morbidity and functional status at discharge or 30 days can help identify patients at risk for poor recovery.

Outcome of patients treated with extracorporeal life support in cardiogenic shock complicating acute myocardial infarction: 1-year result from the ECLS-Shock study.

BACKGROUND: Treatment with extracorporeal life support (ECLS) in acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) fell short of improving myocardial recovery measured by 30 day ejection fraction in the ECLS-SHOCK trial. However, to date, no data regarding impact of ECLS on long-term outcomes exist. METHODS: In this randomized, controlled, prospective, open-label trial, 42 patients with CS complicating AMI were randomly assigned to ECLS (ECLS group, n = 21) or no ECLS (control group, n = 21). The primary endpoint was left ventricular ejection fraction (LVEF) after 30 days. Secondary endpoints included mortality and neurological outcome after 12 months. Evaluation of neurological outcome used the modified Rankin Scale. RESULTS: The 12-month all-cause mortality was 19% in the ECLS group versus 38% in the control group (p = 0.31). Only one patient (control group) died after the initial 30 days. Three patients underwent elective percutaneous coronary intervention (PCI) during follow-up (one in the control and two in the ECLS group). Favorable neurological outcome (modified Rankin Score ≤ 2) was seen in 61.9% of patients in the ECLS group versus 57.1% in the control group (p = 1). CONCLUSION: This pilot study showed that randomized studies with ECLS in CS patients are feasible and safe. Small numbers of included patients impede meaningful conclusions about mortality and neurological outcome. Our findings of numerical differences in mortality and survival with severe neurological impairment give an urgent call for larger multi-centric randomized trials assessing the endpoint of all-cause mortality but also considering the effects on neurological outcome measures.

Update on Weaning from Veno-Arterial Extracorporeal Membrane Oxygenation.

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) provides temporary cardiac and respiratory support and has emerged as an established salvage intervention for patients with hemodynamic compromise or shock. It is thereby used as a bridge to recovery, bridge to permanent ventricular assist devices, bridge to transplantation, or bridge to decision. However, weaning from VA-ECMO differs between centers, and information about standardized weaning protocols are rare. Given the high mortality of patients undergoing VA-ECMO treatment, it is all the more important to answer the many questions still remaining unresolved in this field Standardized algorithms are recommended to optimize the weaning process and determine whether the VA-ECMO can be safely removed. Successful weaning as a multifactorial process requires sufficient recovery of myocardial and end-organ function. The patient should be considered hemodynamically stable, although left ventricular function often remains impaired during and after weaning. Echocardiographic and invasive hemodynamic monitoring seem to be indispensable when evaluating biventricular recovery and in determining whether the VA-ECMO can be weaned successfully or not, whereas cardiac biomarkers may not be useful in stratifying those who will recover. This review summarizes the strategies of weaning of VA-ECMO and discusses predictors of successful and poor weaning outcome.

Isoflurane Sedation in Patients Undergoing Venoarterial Extracorporeal Membrane Oxygenation Treatment for Cardiogenic Shock-An Observational Propensity-Matched Study.

The feasibility and hemodynamic effects of isoflurane sedation in cardiogenic shock in the presence of venoarterial extracorporeal membrane oxygenation treatment are currently unknown. DESIGN: Retrospective single-center study. SETTING: Cardiac ICU of Munich university hospital. PATIENTS/SUBJECTS: Cardiogenic shock patients with venoarterial extracorporeal membrane oxygenation treatment under sedation with volatile isoflurane between November 2018 and October 2019 have been enrolled in this study and were matched by propensity score in a 1:1 ratio with IV sedated patients treated between January 2013 and November 2018 from the cardiogenic shock registry of the university hospital of Munich. MEASUREMENTS AND MAIN RESULTS: Isoflurane sedation was used in 32 patients with cardiogenic shock and venoarterial extracorporeal membrane oxygenation treatment. The mean age of conventionally sedated patients was 58.4 ± 13.8 years and 56.3 ± 11.5 years for patients with isoflurane sedation (p = 0.51). Administration of isoflurane was associated with lower IV sedative drug use during venoarterial extracorporeal membrane oxygenation treatment (86% vs 32%; p = 0.01). Mean systolic arterial pressure was similar (94.3 ± 12.6 vs 92.9 ± 10.5 mm Hg; p = 0.65), but mean heart rate was significantly higher in the conventional sedation group, when compared with the isoflurane group (85.2 ± 20.5 vs 74.7 ± 15.0 beats/min; p = 0.02). Catecholamine doses, venoarterial extracorporeal membrane oxygenation blood and gas flow, ventilation time (304 ± 143 vs 398 ± 272 hr; p = 0.16), bleeding complications bleeding academic research consortium 3a or higher (59.3% vs 65.3%; p = 0.76), and 30-day mortality (59.2% vs 63.4%, p = 0.80) were similar in both groups. The overall sedation costs per patient were significantly lower in the conventional group, when compared with the isoflurane group (537 ± 624 vs 1280 ± 837 €; p < 0.001). CONCLUSIONS: Volatile sedation with isoflurane is feasible-albeit at higher costs-in patients with cardiogenic shock and venoarterial extracorporeal membrane oxygenation treatment and was not associated with higher catecholamine dosage or extracorporeal membrane oxygenation flow rate compared with IV sedation.

Generation of microbubbles in extracorporeal life support and assessment of new elimination strategies.

Occurrence of microbubbles (MB) is a major problem during venoarterial extracorporeal life support (ECLS) with partially severe clinical complications. The aim of this study was to establish an in vitro ECLS setup for the generation and detection of MB. Furthermore, we assessed different MB elimination strategies. Patient and ECLS circuit were simulated using reservoirs, a centrifugal pump, a membrane oxygenator, and an occluder (modified roller pump). The system was primed with a glycerin solution of 44%. Three different revolution speeds (2500, 3000, and 3400 rpm) were applied. For MB generation, the inflow line of the pump was either statically or dynamically (15 rpm) occluded. A bubble counter was used for MB detection. The effectiveness of the oxygenator and dynamic bubble traps (DBTs) was evaluated in regard to MB elimination capacities. MB generation was highly dependent on negative pressure at the inflow line. Increasing revolution speeds and restriction of the inflow led to increased MB activity. The significant difference between inflow and outflow MB volume identified the centrifugal pump as a main source. We could show that the oxygenator's ability to withhold larger MB is limited. The application of one or multiple DBTs leads to a significant reduction in MB count and overall gas volume. The application of DBT can significantly reduce the overall gas volume, especially at high flow rates. Moreover, large MB can effectively be broken down for faster absorption. In general, the incidence of MBs is significantly dependent on pump speed and restriction of the inflow. The centrifugal pump was identified as a major source of MB generation.

Whole blood platelet aggregation kinetics under cardiopulmonary bypass: A pilot study.

Assessing the platelets' functional status during surgery on cardiopulmonary bypass is challenging. This study used multiple electrode impedance aggregometry (Multiplate®) to create a timeline of platelet aggregation changes as induced by cardiopulmonary bypass in antiplatelet-naive patients undergoing elective surgery for mitral valve regurgitation. We performed six consecutive measurements (T1: pre-operatively, T2: after heparinization, T3: 3 min after establishment of cardiopulmonary bypass, T4: immediately after administration of cardioplegia, T5: 5 min after administration of cardioplegia, and T6: 45 min after administration of cardioplegia). Platelet aggregation was determined after stimulation with 3.2-µg/mL collagen, 6.4-µM adenosine diphosphate, and 32-µM thrombin receptor activating peptide. Five patients were included (age: 64 ± 10 years, one female). We observed a decrease in hematocrit levels by -17.1% ± 3.7% (T1 vs T6) with a drop after establishment of cardiopulmonary bypass (T2 vs T3) and slightly decreasing platelet counts by -6.2% ± 7.7% (T1 vs T6). Immediately after establishment of cardiopulmonary bypass (T2 vs T3), we observed reduced platelet aggregation responses for stimulation with adenosine diphosphate (-19.7% ± 12.8%) and thrombin receptor activating peptide (-19.3% ± 6.3%). Interestingly, we found augmented platelet aggregation for all stimuli 45 min after administration of cardioplegia (T5 vs T6) with the strongest increase for collagen (+83.4% ± 42.8%; adenosine diphosphate: +39.0% ± 37.2%; thrombin receptor activating peptide: +34.5% ± 18.5%). Thus, after an initial drop due to hemodilution upon establishment of cardiopulmonary bypass, platelet reactivity increased over time which was not outweighed by decreasing platelet counts due to mechanical platelet destruction and absorption. These findings have implications for rational transfusion, peri-operative antiplatelet therapy, and for the management of patients on other extracorporeal support, such as extracorporeal life support or extracorporeal membrane oxygenation.

Preemptive Extracorporeal Life Support for Surgical Treatment of Severe Constrictive Pericarditis.

BACKGROUND: Surgical treatment of constrictive pericarditis (CP) is particularly challenging because of the increased risk of right heart failure. The necessity of postoperative extracorporeal life support (ECLS) can result in mortality rates of 100%. Preemptive implantation of ECLS may improve postoperative outcomes; however, no data are currently available on its use. We conducted a retrospective study to evaluate the feasibility of our strategy. METHODS: Between September 2012 and June 2016, ECLS was established percutaneously through the groin vessels in 12 individually selected patients with high-risk CP immediately before pericardiectomy in the operating theater as part of the surgical strategy. Prolonged weaning was performed in the intensive care unit. Demographic characteristics, perioperative data, and survival were analyzed. RESULTS: The median patient age was 61.5 years (first quartile, third quartile: 51.3, 68.5 years), with a preoperative central venous pressure of 24 mm Hg (first quartile, third quartile: 21, 28 mm Hg). Furthermore, the pulmonary artery pressure was greater than 60 mm Hg in 50% of patients and a dip plateau sign existed in 75% before surgery. The median duration of ECLS therapy was 132 hours (first quartile, third quartile: 96, 168 hours) with a length of stay on the intensive care unit of 10 days (first quartile, third quartile: 7.0, 16.8 days). There was no intraoperative death. The cumulative 30-day, 1-year, and 5-year survival rates were 83% ± 11%, 75% ± 13%, and 75% ± 13%, respectively. CONCLUSIONS: From our real-world data, preemptive use of perioperative ECLS, assigned by individual team decision in selected patients with severe CP, is a feasible and safe strategy.

Haemadsorption improves intraoperative haemodynamics and metabolic changes during aortic surgery with hypothermic circulatory arrest.

OBJECTIVES: Aortic surgery involving hypothermic circulatory arrest (HCA) results in a systemic inflammatory response that may negatively influence outcome. An extracorporeal haemadsorption (HA) device (CytoSorb®) that removes inflammatory triggers may improve haemodynamic and metabolic reactions due to excessive inflammation and, ultimately, outcome. METHODS: As a single-centre experience, the data of 336 patients who had undergone aortic surgery with HCA between 2013 and 2017 were retrospectively analysed. Patients with HA were matched to patients receiving standard therapy without HA (Control) by propensity score matching and compared subsequently. RESULTS: During aortic surgery with HCA, HA significantly reduced the requirement of norepinephrine (HA: 0.102 µg/kg/min; Control: 0.113; P = 0.043). Severe disturbances of acid-base balance as reflected by a pH lower than 7.19 (HA: 7.1%; Control: 11.6%; P = 0.139), maximum lactate concentrations (HA: 3.75 mmol/l; Control: 4.23 P = 0.078) and the need for tris-hydroxymethylaminomethane buffer (HA: 6.5%; Control: 13.7%; P = 0.045) were less frequent with HA. Compared to standard therapy, HA decreased the need for transfusion of packed red blood cells (1 unit; P = 0.021) and fresh frozen plasma (3 units; P = 0.001), but increased the requirement of prothrombin complex concentrate (800 IE, P = 0.0036). HA did not affect inflammatory laboratory markers on the first postoperative day. Differences in operative mortality (HA: 4.8%; Control: 8.8%) and the length of hospital stay (HA: 13.5 days; Control: 14) were not statistically significant. CONCLUSIONS: HA significantly reduces the need for vasopressors, the amount of transfusion and improves acid-base balance in aortic surgery with HCA. Multicentre prospective trials are required to confirm these results.

Recommendations for extracorporeal cardiopulmonary resuscitation (eCPR): consensus statement of DGIIN, DGK, DGTHG, DGfK, DGNI, DGAI, DIVI and GRC.

Extracorporeal cardiopulmonary resuscitation (eCPR) may be considered as a rescue attempt for highly selected patients with refractory cardiac arrest and potentially reversible aetiology. Currently, there are no randomised, controlled studies on eCPR. Thus, prospective validated predictors of benefit and outcome are lacking. Currently, selection criteria and procedure techniques differ across hospitals and standardised algorithms are lacking. Based on expert opinion, the present consensus statement provides a first standardised treatment algorithm for eCPR.

The cardiotomy reservoir - a preliminary evaluation of a new cell source for cardiovascular tissue engineering.

OBJECTIVES: Cell sources for cardiovascular tissue engineering (TE) are scant. However, the need for an ideal TE cardiovascular implant persists. We investigated the cardiotomy reservoir (CR) as a potential cell source that is more accessible and less ethically problematic. METHODS: CR (n = 10) were removed from the bypass system after surgery. Isolation was performed using different isolation methods: blood samples were taken from the cardiopulmonary bypass and centrifuged at low density. The venous filter screen was cut out and placed into petri dishes for cultivation. The spongelike filter was removed, washed and treated in the same way as the blood samples. After cultivation, cell lines of fibroblasts (FB) and endothelial cells (EC) were obtained for analysis. The cells were seeded on polyurethane patches and analyzed via scanning electron microscopy (SEM), Life/Dead assay and immunohistochemistry. RESULTS: No correlation between age, time of surgery and quality of cells was observed. The successful extraction of FB and was proven by positive staining results for TE-7, CD31 and vWF. Cell morphology, cytoskeleton staining and quantification of proliferation using WST-1 assay resembled the cells of the control group in all ways. The topography of a confluent and vital cell layer after cell seeding was displayed by SEM analysis, Life/Dead Assay and immunohistochemistry. The establishment of an extracellular matrix (ECM) was proven by positive staining for collagen IV, laminin, fibronectin and elastin. CONCLUSIONS: Viable FB and EC cell lines were extracted from the CR after surgery. Easy access and high availability make this cell source destined for widespread application in cardiovascular tissue engineering.

Remote ECLS-Implantation and Transport for Retrieval of Cardiogenic Shock Patients.

OBJECTIVE: Extracorporeal life support (ECLS) emerges as a salvage option in therapy refractory cardiogenic shock but is limited to highly specialized tertiary care centers. Critically ill patients are often too unstable for conventional transport. Mobile ECLS programs for remote implantation and subsequent air or ground-based transport for patient retrieval could solve this dilemma and make full-spectrum advanced cardiac care available to patients in remote hospitals in whom shock otherwise might be fatal. METHODS: From December 2012 to March 2016, 40 patients underwent venoarterial ECLS implantation in remote hospitals with subsequent transport to our center and were retrospectively analyzed. The mobile ECLS team was available 24/7, implantation was performed percutaneously bedside, and compact support systems designed for transport were used. RESULTS: Twenty percent of the patients were female; the mean age was 55 ± 10 years, and the mean Interagency Registry for Mechanically Assisted Circulatory Support score was 1.3 ± 0.5. Patient retrieval was accomplished via ground-based (n = 29, 72.5%, mean distance = 27.9 ± 29.7 km [range, 5.6-107.1 km]) or air (n = 11, mean distance = 62.4 ± 27.2 km [range, 38.9-116.4 km]) transport. No ECLS-related complications occurred during transport. The ECLS system could be explanted in 65.0% (n = 26) of patients, and the 30-day survival rate was 52.5% (n = 21). CONCLUSION: Remote ECLS implantation and interfacility transport on ECLS are feasible and effective. Interdisciplinary teams and full-spectrum cardiac care are essential to achieve optimal outcomes. Rapid-response ECLS networks have the potential to substantially increase the survival of cardiogenic shock patients.

Extracorporeal Circulation During Lung Transplantation Procedures: A Meta-Analysis.

Extracorporeal circulation (ECC) is an invaluable tool in lung transplantation (lutx). More than the past years, an increasing number of centers changed their standard for intraoperative ECC from cardiopulmonary bypass (CPB) to extracorporeal membrane oxygenation (ECMO) - with differing results. This meta-analysis reviews the existing evidence. An online literature research on Medline, Embase, and PubMed has been performed. Two persons independently judged the papers using the ACROBAT-NRSI tool of the Cochrane collaboration. Meta-analyses and meta-regressions were used to determine whether veno-arterial ECMO (VA-ECMO) resulted in better outcomes compared with CPB. Six papers - all observational studies without randomization - were included in the analysis. All were considered to have serious bias caused by heparinization as co-intervention. Forest plots showed a beneficial trend of ECMO regarding blood transfusions (packed red blood cells (RBCs) with an average mean difference of -0.46 units [95% CI = -3.72, 2.80], fresh-frozen plasma with an average mean difference of -0.65 units [95% CI = -1.56, 0.25], platelets with an average mean difference of -1.72 units [95% CI = -3.67, 0.23]). Duration of ventilator support with an average mean difference of -2.86 days [95% CI = -11.43, 5.71] and intensive care unit (ICU) length of stay with an average mean difference of -4.79 days [95% CI = -8.17, -1.41] were shorter in ECMO patients. Extracorporeal membrane oxygenation treatment tended to be superior regarding 3 month mortality (odds ratio = 0.46, 95% CI = 0.21-1.02) and 1 year mortality (odds ratio = 0.65, 95% CI = 0.37-1.13). However, only the ICU length of stay reached statistical significance. Meta-regression analyses showed that heterogeneity across studies (sex, year of ECMO implementation, and underlying disease) influenced differences. These data indicate a benefit of the intraoperative use of ECMO as compared with CPB during lung transplant procedures regarding short-term outcome (ICU stay). There was no statistically significant effect regarding blood transfusion needs or long-term outcome. The superiority of ECMO in lutx patients remains to be determined in larger multi-center randomized trials.

Patient management in aortic arch surgery†.

SummaryAortic arch surgery requires complex patient management beyond the manual replacement of the diseased vessel. These procedures include (i) a thorough and pathologically adjusted preoperative evaluation, (ii) initiation and control of cardiopulmonary bypass, (iii) cerebral protection strategies and (iv) techniques to protect the abdominal end organs during prolonged operations. Due to the complexity of aortic arch procedures, multimodal real-time surveillance is required during all stages of the operation. Although having the patient survive the operation is the major goal, further observation is necessary because of the chronicity of the disease. This review summarizes specific aspects of patient management during and after operations requiring periods of circulatory arrest, without necessarily referring to all studies on this topic. The pros and cons of different strategies are weighed against each other, including the personal experience of the authors. A number of questions are raised without providing a 'right' or 'wrong' answer. We show that a number of different well-established strategies can result in comparable excellent long-lasting surgical results.

Potential impact of oxygenators with venous air trap on air embolism in veno-arterial Extracorporeal Life Support.

BACKGROUND: Air embolism is a potentially fatal but underrecognized complication in Extracorporeal Life Support (ECLS). Oxygenators containing venous air traps have been developed to minimize the risk of air embolism in daily care. OBJECTIVE: We reproduced air embolism as occurring via a central venous catheter in an experimental setting to test the potential of oxygenators with and without venous bubble trap (VBT) to withhold air. METHODS: An in vitro ECLS circuit was created and a central venous catheter with a 3-way stopcock and a perforated male luer cap was inserted into the inflow line. Three different oxygenators with and without VBT and their capability to withhold air were examined. After 60 seconds of stable ECLS flow, the stopcock was opened towards the atmosphere for 3 minutes. Afterwards, air accumulation within the oxygenator was determined. RESULTS: Comparison of the total air entrapment showed a significant superiority of the oxygenators with VBT (p < 0.001). All oxygenators were able to partly withhold macro air boli, however, the capacity of oxygenators with VBT was higher. Passing through the oxygenator resulted in a reduction of microbubbles in all cases. CONCLUSIONS: Macro air emboli can be substantially reduced by usage of oxygenators that contain a VBT, whereas the capability to withhold microbubbles to a vast extent seems to depend on the intrinsic oxygenator's membrane.

When all else fails: extracorporeal life support in therapy-refractory cardiogenic shock.

OBJECTIVES: No guidelines for mechanical circulatory support in patients with therapy-refractory cardiogenic shock and multiorgan failure including ongoing cardiopulmonary resuscitation (CPR) exist. To achieve immediate cardiopulmonary stabilization, we established an interdisciplinary concept with on-site percutaneous extracorporeal life support (ECLS) implantation. METHODS: From February 2012 to November 2014, 96 patients were deemed eligible for ECLS implantation. Establishing ECLS was successful in 87 patients (mean age 54 ± 13 years, 16% female, initial flow 4.4 ± 0.9 l/min). Aetiologies included acute coronary syndromes (n = 52, 60%), cardiomyopathies (n = 25, 29%) and other pathologies. Fifty-nine patients (68%) had been resuscitated, and in 27 (31%), implantation was performed during CPR; 11 patients (13%) were awake at implantation and 20 (23%) underwent implantation in the referring hospital. RESULTS: Metabolic parameters differed in non-survivors versus survivors before ECLS implantation (pH 7.15 ± 0.23 vs. 7.27 ± 0.18, P = 0.007; lactate levels 10.90 ± 6.00 mmol/l vs. 8.79 ± 5.78 mmol/l, P = 0.091) and 6 h postimplantation (pH 7.27 ± 0.11 vs. 7.37 ± 0.11, P < 0.001; lactate levels 10.19 ± 5.52 mmol/l vs. 5.52 ± 4.17 mmol/l, P < 0.001). Altogether 44 patients could be weaned, and 9 were bridged to assist device implantation and 1 to heart transplantation. The mean time of support was 6 days, and the 30-day survival rate was 47% (n = 41). CONCLUSIONS: ECLS serves as a bridge-to-decision and bridge-to-treatment device. Our interdisciplinary ECLS programme achieved acceptable survival of critically ill patients despite a substantial percentage of patients having been resuscitated and no absolute exclusion criteria. Further studies defining inclusion- and exclusion criteria might additionally improve outcome.