Christof Schmid

University Hospital Regensburg, Ratisbon, Bavaria, Germany

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Publications (412)1094.5 Total impact

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    ABSTRACT: Transcatheter valve-in-valve (VIV) implantation evolved as a therapeutic alternative, despite an increased risk of coronary obstruction in comparison with a regular transcatheter aortic valve implantation (TAVI). We report a comprehensive single-institution experience emphasizing strategies to reduce the risk of myocardial ischemia. Since 2009, 639 patients underwent a TAVI procedure in our institution. All patients are prospectively collected into an institutional registry. In total 31 patients underwent a VIV procedure at our institution (age 77.8 ± 6.3 years; The Society or Thoracic Surgeons predicted risk of mortality 20.9% ± 8.8%; New York Heart Association (NYHA) 3.0 ± 0.6). Degenerated bioprostheses included 24 Mitroflow, 6 Edwards Perimount, and Cryo-Valve O' Brien with label sizes from 21 to 27 mm. The type of failure was mostly regurgitation with or without concomitant stenosis (78%). Patients were provided with 5 Medtronic CoreValves, 15 Edwards SapienXT, 1 Edwards Sapien 3, 7 Medtronic Engager, and 3 Symetis Acurate TA valves. The procedural success rate was 88%. The left main stem was occluded in 1 patient (Sapien XT 26 in a Mitroflow 25 mm) who underwent emergent revascularization. Two patients suffering from a degenerated Mitroflow prosthesis needed a second valve (Sapien XT). Two patients with a degenerated Mitroflow prosthesis treated with a Sapien XT developed postprocedural myocardial ischemia and deceased on postoperative days 1 and 2, accounting to an overall incidence of coronary insufficiency associated to the VIV procedure of 10%. With the introduction of valves allowing commissural alignment (Acurate TA) and leaflet capturing as well (Engager) no further coronary insufficiency occurred. The mean gradient decreased significantly from 39.3 ± 14.0 to 16.1 ± 7.2 mm Hg (p = 0.002). Post-procedural regurgitation was classified as trace in 7 patients (23%) and moderate in 4 patients (13%). The 30-day survival was 77% with a significantly improved NYHA class of 1.79 ± 0.58 (p = 0.001). Jeopardizing coronary blood flow is likely in stenotic and calcified bioprostheses, particularly in tubelike aortic sinuses. Planning, imaging, and the use of valves allowing commissural alignment as well as leaflet capturing seem to reduce the risk. Further studies are necessary to support this hypothesis. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
    The Annals of Thoracic Surgery 02/2015; DOI:10.1016/j.athoracsur.2014.11.047 · 3.63 Impact Factor
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    ABSTRACT: Human umbilical vessels have been recognized as a valuable and widely available resource for vascular tissue engineering. Whereas endothelium-denuded human umbilical veins (HUVs) have been successfully seeded with a patient-derived neoendothelium, decellularized vessels may have additional advantages, due to their lower antigenicity. The present study investigated the effects of three different decellularization procedures on the histological, mechanical and seeding properties of HUVs. Vessels were decellularized by detergent treatment (Triton X-100, sodium deoxycholate, IGEPAL-CA630), osmotic lysis (3 m NaCl, distilled water) and peroxyacetic acid treatment. In all cases, nuclease treatments were required to remove residual nucleic acids. Decellularization resulted in a partial loss of fibronectin and laminin staining in the subendothelial layer and affected the appearance of elastic fibres. In addition to removing residual nucleic acids, nuclease treatment weakened all stainings and substantially altered surface properties, as seen in scanning electron micrographs, indicating additional non-specific effects. Detergent treatment and osmotic lysis caused failure stresses to decrease significantly. Although conditioned medium prepared from decellularized HUV did not severely affect endothelial cell growth, cells seeded on decellularized HUV did not remain viable. This may be attributed to the partial removal of essential extracellular matrix components as well as to changes of surface properties. Therefore, decellularized HUVs appear to require additional modifications in order to support successful cell seeding. Replacing the vessels' endothelium may thus be a superior alternative to decellularization when creating tissue-engineered blood vessels with non-immunogenic luminal interfaces. Copyright © 2012 John Wiley & Sons, Ltd.
    Journal of Tissue Engineering and Regenerative Medicine 01/2015; 9(1). DOI:10.1002/term.1603 · 4.43 Impact Factor
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    ABSTRACT: Technical complications are a known hazard in veno-venous extracorporeal membrane oxygenation (vvECMO). Identifying these complications and predictive factors indicating a developing system-exchange was the goal of the study. Retrospective study on prospectively collected data of technical complications including 265 adult patients (Regensburg ECMO Registry, 2009-2013) with acute respiratory failure treated with vvECMO. Alterations in blood flow resistance, gas transfer capability, hemolysis, coagulation and hemostasis parameters were evaluated in conjunction with a system-exchange in all patients with at least one exchange (n = 83). Values presented as median (interquartile range). Patient age was 50(36-60) years, the SOFA score 11(8-14.3) and the Murray lung injury Score 3.33(3.3-3.7). Cumulative ECMO support time 3411 days, 9(6-15) days per patient. Mechanical failure of the blood pump (n = 5), MO (n = 2) or cannula (n = 1) accounted for 10% of the exchanges. Acute clot formation within the pump head (visible clots, increase in plasma free hemoglobin (frHb), serum lactate dehydrogenase (LDH), n = 13) and MO (increase in pressure drop across the MO, n = 16) required an urgent system-exchange, of which nearly 50% could be foreseen by measuring the parameters mentioned below. Reasons for an elective system-exchange were worsening of gas transfer capability (n = 10) and device-related coagulation disorders (n = 32), either local fibrinolysis in the MO due to clot formation (increased D-dimers [DD]), decreased platelet count; n = 24), or device-induced hyperfibrinolysis (increased DD, decreased fibrinogen [FG], decreased platelet count, diffuse bleeding tendency; n = 8), which could be reversed after system-exchange. Four MOs were exchanged due to suspicion of infection. The majority of ECMO system-exchanges could be predicted by regular inspection of the complete ECMO circuit, evaluation of gas exchange, pressure drop across the MO and laboratory parameters (DD, FG, platelets, LDH, frHb). These parameters should be monitored in the daily routine to reduce the risk of unexpected ECMO failure.
    PLoS ONE 12/2014; 9(12):e112316. DOI:10.1371/journal.pone.0112316 · 3.53 Impact Factor
  • M Freundt, A Haneya, C Schmid, S Hirt
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    ABSTRACT: Patients with left ventricular assist devices (LVADs) who develop stage IV sacral pressure sores (SPS) have an increased procedural risk. We present the complications, including severe intra- and postoperative bleeding, diarrhea with metabolic acidosis, volume loss and acute on chronic renal failure, flap dehiscence and late LVAD outflow cannula thrombosis, in a 54-year-old male who underwent diverting ileostomy (DI) and subsequent fasciocutaneous flap (FCF) surgery for stage IV SPS while supported with an LVAD. Our experience suggests that, despite continuous heparinization, life-threatening thrombotic complications, such as device clotting, can occur. Therefore, the benefit of intervention has to outweigh the risk of bleeding, which should be managed with meticulous surgical technique and substitution of red blood cells rather than the reversal of heparinization or the substitution of clotting factors. Continuation of double anti-platelet therapy should also be considered.
    Perfusion 11/2014; DOI:10.1177/0267659114560043 · 1.08 Impact Factor
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    ABSTRACT: Polymethylpentene membrane oxygenators used in venovenous extracorporeal membrane oxygenation (vvECMO) differ in their physical characteristics. The aim of the study was to analyze the gas transfer capability of different ECMO systems in clinical practice, as the choice of the appropriate system may be influenced by the needs of the patient.
    Intensive Care Medicine 10/2014; DOI:10.1007/s00134-014-3489-z · 5.54 Impact Factor
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    ABSTRACT: Objectives Re-exploration after cardiac surgery remains a frequent complication with adverse outcomes. The aim of this study was to evaluate the impact of timing and indication of re-exploration on outcome. Methods A retrospective, observational study on a cohort of 209 patients, who underwent re-exploration after cardiac surgery between January 2005 and December 2011, was performed. The cohort was matched for age, gender, and procedure with patients who were not re-explored during the same period. Results The intraoperative and postoperative transfusion requirements were higher in the re-exploration group (p < 0.01). Patients in the re-exploration group had significantly higher incidences of postoperative acute renal injury (10.0 vs. 3.3%), sternal wound (9.1 vs. 2.4%) and pulmonary (13.4 vs. 4.3%) infections, longer ventilation time (22 [range, 14-52] vs. 12 [range, 9-16] hours) and intensive care unit stay (5 [range, 3-7] vs. 2 [range, 2-4] days), and higher mortality rate (9.6 vs. 3.3%). However, the multivariate logistic regression analysis demonstrated that not the re-exploration itself, but the deleterious effects of re-exploration (blood loss and transfusion requirement) were independent risk factors for mortality. Mortality was 5.3% for patients who were re-explored within the first 12 hours and 20.3% for patients who were re-explored after 12 hours (p = 0.003). Mortality was 3.6% for patients with bleeding and 31.4% for patients with cardiac tamponade for indication of re-exploration (p < 0.001). Conclusions This study suggests that re-exploration after cardiac surgery is associated with increased mortality and morbidity. Patients with delayed re-exploration and suffering from cardiac tamponade have adverse outcome.
    The Thoracic and Cardiovascular Surgeon 09/2014; 63(01). DOI:10.1055/s-0034-1390154 · 1.08 Impact Factor
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    ABSTRACT: Objective of this study was to evaluate the impact of age on comparative early outcomes after coronary artery bypass graft surgery (CABG) with minimized (MECC) and conventional extracorporeal circulation (CECC).
    Journal of Cardiothoracic Surgery 08/2014; 9(1):143. DOI:10.1186/s13019-014-0143-3 · 1.02 Impact Factor
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    ABSTRACT: Oxygenator thrombosis is a serious complication in extracorporeal membrane oxygenation (ECMO) and may necessitate a system exchange. Coagulation and fibrinolysis parameters, flow dynamics and gas transfer performance are currently used to evaluate the degree of oxygenator thrombosis, but there is no technical approach for direct visualization and quantification of thrombotic deposits within the membrane oxygenator (MO).We used multidetector computed tomography (MDCT) with 3D post-processing to assess the incidence of oxygenator thrombosis, to quantify thrombus extent, and to localize clot distribution. Twenty heparin-coated MOs after successful weaning were analyzed. Mean ECMO support time was 7 ± 4 days, mean activated partial thromboplastin time (aPTT) during ECMO was 59 ± 20 seconds. Thrombotic deposits were detected in all MOs. The mean clot volume was 51.7 ± 22.3 cm³. All thrombotic deposits were located in the venous, i.e. inlet part of the device, without apparent evidence of embolization in patients. There was no correlation between clot volume and ECMO support time or aPTT.Clot formation within the MO is a common finding in ECMO despite adequate systemic anticoagulation. The clinical significance of thrombus formation and its influence on gas exchange capacity and hemostatic complications have to be addressed in further studies.
    ASAIO journal (American Society for Artificial Internal Organs: 1992) 08/2014; DOI:10.1097/MAT.0000000000000133 · 1.39 Impact Factor
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    ABSTRACT: Zusammenfassung Eine pulmonale Hypertonie kann sowohl kardiale als auch pulmonale Ursachen haben und führt in der Herz-Thorax-Chirurgie zu einer signifikant erhöhten Letalität. Nachfolgend werden die medikamentösen und chiurgischen Therapieansätze dafür erläutert.
    Zeitschrift für Herz- Thorax- und Gefäßchirurgie 06/2014; 16(3). DOI:10.1007/s00398-002-0346-0
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    ABSTRACT: LVAD speed adjustment according to a functioning aortic valve has hypothetic advantages but could lead to submaximal support. The consequences of an open aortic valve policy on exercise capacity and hemodynamics have not yet been investigated systematically.
    Journal of Cardiothoracic Surgery 05/2014; 9(1):93. DOI:10.1186/1749-8090-9-93 · 1.02 Impact Factor
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    ABSTRACT: Veno-venous extracorporeal membrane oxygenation (vvECMO) can be a life-saving therapy in patients with severe acute lung failure refractory to conventional therapy. Nevertheless, vvECMO is a procedure associated with high costs and resource utilization. The aim of this study was to assess published models for prediction of mortality following vvECMO and optimize an alternative model. Established mortality risk scores were validated to assess their usefulness in 304 adult patients undergoing vvECMO for refractory lung failure at the University Medical Center Regensburg from 2008 to 2013. A parsimonious prediction model was developed based on variables available before ECMO initiation using logistic regression modelling. We then assessed whether addition of variables available one day after ECMO implementation enhanced mortality prediction. Models were internally validated and calibrated by bootstrapping (400 runs). Predictive ability, goodness-of-fit and model discrimination were compared across the different models. In the present study population, existing mortality prediction tools for vvECMO patients showed suboptimal performance. Evaluated before vvECMO initiation, a logistic prediction model comprising age, immunocompromised state, artificial minute ventilation, pre-ECMO serum lactate and haemoglobin concentrations showed best mortality prediction in our patients (area under curve, AUC: 0.75). Additional information about norepinephrine dosage, fraction of inspired oxygen, C-reactive protein and fibrinogen concentrations the first day following ECMO initiation further improved discrimination (AUC: 0.79, P = 0.03) and predictive ability (likelihood ratio test, P < 0.001). When classifying patients as lower (<40%) or higher (>80%) risk based on their predicted mortality, the pre-ECMO and day1-on-ECMO models had negative/positive predictive values of 76%/82% and 82%/81%, respectively. While pre-ECMO mortality prediction remains a challenge due to large patient heterogeneity, evaluation one day after ECMO initiation may improve the ability to separate lower- and higher-risk patients. Our findings support the clinical perception that chronic health condition, high comorbidity and reduced functional reserves are strongly related to survival during and following ECMO support. Renewed evaluation the first day after ECMO initiation may provide enhanced guidance for further handling of ECMO patients. Despite the usefulness of prediction models, thorough clinical evaluation should always represent the cornerstone in decision for ECMO.
    Critical care (London, England) 04/2014; 18(2):R67. DOI:10.1186/cc13824 · 5.04 Impact Factor
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    ABSTRACT: Postoperative Acute Kidney Injury (AKI) after coronary artery bypass grafting (CABG) is a common complication associated with significant morbidity and mortality. Cardiopulmonary bypass (CPB) is accepted to contribute to the occurrence of AKI and is of particular importance as it can be avoided by using the off-pump technique. However the renoprotective properties of off-pump (CABG) are controversial. This analysis evaluates the impact of cardiopulmonary bypass on renal function. A matched-pair analysis of 1428 patients undergoing coronary artery bypass grafting was conducted. The patients were stratified according to their preoperative renal function and to risk factors for postoperative AKI. The development of the glomerular filtration rate (GFR) from before surgery until hospital discharge was analyzed. Incidence of AKI were analyzed. Furthermore the impact of CPB duration on postoperative GFR was assessed. The occurrence of AKI increases the risk of thirty-day mortality (odds ratio of 4.3). The postoperative GFR decreases significantly after coronary artery bypass grafting but does not differ between onpump and offpump CABG (60.2 +/- 24.5 vs 60.7 +/- 24.8; p = 0.54). No difference regarding the incidence (26.6% vs 25%) and severity of AKI between cardiopulmonary bypass and the off-pump technique could be found. Duration of cardiopulmonary bypass does not correlate with the decline in postoperative glomerular filtration rate (Pearson Product Moment Correlation; p > 0.050). Neither the mere use nor duration of cardiopulmonary bypass proofed to be a risk factor for developing postoperative AKI in CABG patients with a comparable preoperative risk profile for postoperative renal dysfunction. Furthermore, the severity of postoperative AKI is not affected by the use of cardiopulmonary bypass.
    Journal of Cardiothoracic Surgery 01/2014; 9(1):20. DOI:10.1186/1749-8090-9-20 · 1.02 Impact Factor
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    ABSTRACT: Polyetherurethane (PEU) is in use for blood-contacted devices because of its excellent mechanical properties. However, poor hemocompatibility of the hydrophobic material required surface modification or endothelialization. To increase the biocompatibility of PEU, the polymer was coated with a titaniumcarboxonitride [Ti(C,N,O)] layer by a plasma-activated chemical vapor deposition (PACVD) process. Biocompatibility of titaniferously coated PEU was verified using static and dynamic cell culture techniques. Titaniferous coating significantly improved proliferation and mitochondrial activity of human endothelial cells on PEU. These cells captured significantly less mononuclear cells and platelets. Under shear stress for up to 72 hours, titaniferous coating increased endothelial cell adhesion, spreading, and cell density to form an organized monolayer covering the whole luminal surface of vascular PEU grafts. In summary, coating of PEU surfaces with Ti(C,N,O) might be a promising strategy to improve the biocompatibility of biomedical biomaterials. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.
    Journal of Biomedical Materials Research Part B Applied Biomaterials 01/2014; 102(1). DOI:10.1002/jbm.b.32990 · 2.31 Impact Factor
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    ABSTRACT: Polycarbonateurethanes (PCU) and polyetherurethanes (PEU) are used for medical devices, however their bio- and haemocompatibility is limited. In this study, the effect of titaniferous upgrading of different polyurethanes on the bio-and haemocompatibility was investigated by endothelial cell (EC) adhesion/proliferation and platelet adhesion (scanning electron microscopy), respectively. There was no EC adhesion/proliferation and only minor platelet adhesion on upgraded and pure PCU (Desmopan). PEUs (Texin 985, Tecothane 1085, Elastollan 1180A) differed in their cyto-and haemocompatibility. While EC adhesion depended on the type of PEU, any proliferative activity was inhibited. Additional titaniferous upgrading of PEU induced EC proliferation and increased metabolic activity. However, adherent ECs were significantly activated. While Texin was highly thrombotic, only small amounts of platelets adhered onto Tecothane and Elastollan. Additional titaniferous upgrading reduced thrombogenicity of Texin, preserved haemocompatibility of Elastollan, and increased platelet activation/aggregation on Tecothane. In conclusion, none of the PUs was cytocompatible; only titaniferous upgrading allowed EC proliferation and metabolism on PEUs. Haemocompatibility depended on the type of PU.
    Materials 12/2013; 7(2). DOI:10.3390/ma7020623 · 1.88 Impact Factor
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    ABSTRACT: Early markers of oxygenator dysfunction during prolonged use of extracorporeal membrane oxygenation (ECMO) are important for timely exchange to avoid sudden loss of function due to clot formation within the system. The measurement of d-dimers (DDs) in plasma might be a marker for early diagnosis of thrombus formation and dysfunction of heparin-coated membrane oxygenators (MOs). This is a retrospective study on prospectively collected data of 24 adult acute respiratory distress syndrome patients requiring long-term veno-venous ECMO with at least 1 MO exchange. Kinetics of coagulation, inflammation, and oxygenator function were analyzed before and after MO exchange. Median (interquartile range) support duration is 20 (15-29) days. Thirty-four MOs had to be replaced. Exchange occurred due to visible thrombus formation in the MO (n = 16), worsening gas exchange (n = 11), increased blood flow resistance (n = 1), and activation of coagulation with diffuse bleeding (n = 6). In 15 cases, DDs were continuously elevated and, therefore, not suitable as marker for MO exchange. In the remaining 19 cases, DDs increased significantly within 3 days before exchange from 15 (9-20) to 30 (21-35) mg/dL (P = .002) and declined significantly within 1 day thereafter to 13 (7-17) mg/dL (P = .003). An increase in plasma DD concentration in absence of other explaining pathology can be helpful in predicting an MO exchange in miniaturized heparin-coated ECMO systems.
    Journal of critical care 12/2013; DOI:10.1016/j.jcrc.2013.12.008 · 2.13 Impact Factor
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    ABSTRACT: Extracorporeal life support is a worldwide expanding technology for patients in critical cardiogenic shock. The device is usually attached to the femoral vessels using percutaneous techniques. Despite sufficient extracorporeal circulatory support, an unclear number of patients develop high end-diastolic pressures leading to left ventricular distension and pulmonary edema, and ventricular thrombus formation may evolve. This article discusses the strategies to prevent ventricular distension by conservative, interventional, and surgical means, also illustrated by case presentations.
    ASAIO journal (American Society for Artificial Internal Organs: 1992) 11/2013; 59(6):547-53. DOI:10.1097/MAT.0b013e3182a4b2f6 · 1.39 Impact Factor
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    ABSTRACT: Membrane oxygenator (MO) failure is a known hazard during venovenous extracorporeal membrane oxygenation (v-v ECMO) therapy. Knowledge about technical and performance details of different ECMO systems (Maquet, Rastatt, Germany; Medos, Stolberg, Germany; Sorin, Modena, Italy) licensed for adults with acute lung failure might improve their handling. This retrospective study comprises 186 adult patients (Regensburg ECMO Registry) treated with v-v ECMO. Flow dynamic data were used to analyze the performance of different blood pumps, cannula types, and MOs to maintain an adequate blood flow (1-5 L/min). Usage of the Medos ECMO system in critically ill patients required a higher pump speed and generated a higher pressure drop across the MO (dpMO), however, without an increase in free plasma hemoglobin. The dpMO depended on the type of MO and increased with blood flow as expected. Type-specific normal values are reported. A distinct increase in dpMO above normal values within 1 day required an immediate MO exchange. This was an infrequent technical complication (3%). Finally, pressure-flow performance of single dual-lumen cannulas (27 Fr) was comparable with small single-lumen cannulas (15 Fr), without an increased risk of technical-induced hemolysis. Despite different performances, all current commercially available adult v-v ECMO systems produce adequate blood flow without an increased risk in technical-induced hemolysis. Familiarity with the specific properties of individual systems allows early detection of technical complications. Additionally, the choice of an adequate cannula requires a closer consideration of the individual patient situation.
    Artificial Organs 10/2013; 38(5). DOI:10.1111/aor.12180 · 1.87 Impact Factor
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    ABSTRACT: Extracorporeal life support (ECLS) is a rescue option in critically ill patients. Since fast available and appropriate for respiratory and circulatory failure, it is frequently applied in resuscitation scenarios. Neurological injury is a complication common in ECLS patients limiting outcome, particularly after resuscitation. In this study, the institutional ECLS database was used to correlate neuron-specific enolase (NSE) serum peak values with outcome of patients supported with venoarterial (VA) ECLS during cardiopulmonary resuscitation (CPR). From January 2011 to August 2012, 31 patients were provided with a VA ECLS during CPR (external cardiac massage). Serum NSE peaks were monitored and correlated with neurological outcome and hospital mortality. Patients were divided into two groups with mild-to-moderate and high NSE levels (cut-off value 100 μg/l). High NSE levels were seen in 7 patients (mean 218 ± 155 μg/l) and mild-to-moderate levels in 24 patients (50 ± 23 μg/l, P = 0.0001). Duration of extracoporeal support was comparable in both groups (6.3 ± 7.5 vs 5.0 ± 4.5 days, P = n.s.). Patients with mild-to-moderate NSE levels were significantly older than those with high NSE levels (58 ± 16 vs 44 ± 15 years, P = 0.02). Six patients with high NSE levels (86%) developed severe neurological complications. Though 4 patients could be weaned from extracorporeal support, hospital mortality was 86% (6 patients). In contrast, patients with mild-to-moderate NSE levels had a hospital mortality of 46% (11 patients). Eighteen patients (75%) could be weaned from the device, and incidence of major neurological events was 29% (6 patients) only. Serum pH and lactate levels before ECLS implantation were significantly lower in patients with mild-to-moderate NSE values (pH: 7.23 ± 0.04 vs 6.93 ± 0.12, P = 0.039; lactate: 106 ± 11 vs 161 ± 16 mg/l, P = 0.023). High NSE serum levels after ECLS correspond to poor neurological outcome and considerable mortality. Therefore, early neuroimaging is reasonable for determining therapeutic strategies in patients with high NSE peaks after resuscitation and extracorporeal support.
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 07/2013; 45(3). DOI:10.1093/ejcts/ezt370 · 2.40 Impact Factor
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    ABSTRACT: OBJECTIVES Based on continuous technical innovations and recent research, extracorporeal membrane oxygenation (ECMO) has become a promising tool in the treatment of patients with acute (cardio)pulmonary failure. Nevertheless, any extracorporeal technique requires a high degree of experience and knowledge, so that a restriction to specialized centres seems to be reasonable. As a consequence of this demand, the need for inter-hospital transfer of patients with severely impaired (cardio)pulmonary function is rising. Unfortunately, most of the ECMO devices used in the clinical setting are not suitable for inter-hospital transport because of their size, weight or complexity. In this article, we describe our first experiences with the airborne transport of 6 patients on a new portable, miniaturized and lightweight extracorporeal circulation system, the Medos deltastream® DP3.METHODS Six patients suffering acute respiratory failure were taken on venovenous ECMO (DP3) out-of-centre and transferred to the University Medical Center Regensburg by helicopter. All cardiorespiratory-relevant parameters of the patients and the technical functioning of the device were continuously monitored and documented.RESULTSImplantation of the device and air-supported transport were performed without any technical complications. The patients were transported from a distance of 66-178 km, requiring a time of 40-120 min. With the help of the new deltastream® DP3 ECMO device, a prompt stabilization of the cardiopulmonary function could be achieved in all patients. One patient was under ongoing cardiopulmonary resuscitation by the time our ECMO team arrived at the peripheral hospital and died shortly after arrival in the central emergency ward.CONCLUSIONS Our experience shows that the deltastream® DP3 is an absolutely reliable and safe ECMO device that could gain growing importance in the field of airborne transportation of patients on ECMO due to its unsophisticated, miniaturized and lightweight characteristics.
    Interactive Cardiovascular and Thoracic Surgery 07/2013; 17(5). DOI:10.1093/icvts/ivt320 · 1.11 Impact Factor
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    ABSTRACT: Despite heparin coating and systemic anticoagulation, thrombotic clot formation is a serious complication in extracorporeal membrane oxygenation (ECMO). We describe our first results of visualization of thrombotic deposits in ECMO devices using advanced multidetector computed tomography (MDCT). A bioline-coated polymethylpentene membrane oxygenator (MO) after 8 days of ECMO treatment (device 1) and a factory-sealed MO serving as an internal quality control (device 2) were analyzed with three-dimensional (3D) visualization volume rendering technique (VRT) using a 0.6 mm voxel isotropic MDCT dataset. After the computed tomography (CT) scan, device 1 was anatomically dissected for direct visualization of potential deposits and further analyzed by scanning electron microscopy (SEM). The VRT 3D model based on the MDCT dataset of device 1 showed red-coded areas within the gas exchange surface of the device consistent with fibrous and cellular deposits. These deposits could be confirmed by anatomical dissection of the device and by SEM. Device 2 showed no signs of clot formation in MDCT using the same VRT settings. It was demonstrated that MDCT with VRT is able to detect thrombotic deposits in ECMO devices under ex vivo conditions. MDCT allows direct visualization of the actual thrombus load of a used ECMO device as well as the quantification of the thrombus volume and could, therefore, play a significant role in better understanding the oxygenator thrombosis in modern ECMO treatment.
    ASAIO journal (American Society for Artificial Internal Organs: 1992) 07/2013; 59(4):439-441. DOI:10.1097/MAT.0b013e3182976eff · 1.39 Impact Factor

Publication Stats

3k Citations
1,094.50 Total Impact Points

Institutions

  • 2008–2015
    • University Hospital Regensburg
      • Klinik und Poliklinik für Herz-, Thorax- und herznahe Gefäßchirurgie
      Ratisbon, Bavaria, Germany
    • Universität Regensburg
      • Department of Cardiac, Thoracic and Vascular Surgery near the Heart
      Ratisbon, Bavaria, Germany
  • 2004–2012
    • University of Duisburg-Essen
      • • Institut für Psychologie
      • • Department of Internal and Integrative Medicine
      Essen, North Rhine-Westphalia, Germany
  • 2011
    • Universitätsklinikum Freiburg
      Freiburg an der Elbe, Lower Saxony, Germany
  • 1996–2010
    • Universitätsklinikum Münster
      • Department für Kardiologie und Angiologie
      Muenster, North Rhine-Westphalia, Germany
    • Justus-Liebig-Universität Gießen
      • Department of Internal Medicine
      Gieben, Hesse, Germany
  • 1995–2010
    • University of Münster
      • Department of Neurology
      Muenster, North Rhine-Westphalia, Germany
  • 2009
    • Martin Luther University of Halle-Wittenberg
      • Clinic for Internal Medicine III
      Halle-on-the-Saale, Saxony-Anhalt, Germany
  • 2002–2004
    • Columbia University
      New York, New York, United States