How to Recondition Ex Vivo Initially Rejected Donor Lungs for Clinical Transplantation: Clinical Experience from Lund University Hospital

A major problem in clinical lung transplantation is the shortage of donor lungs. Only about 20% of donor lungs are accepted for transplantation. We have recently reported the results of the first six double lung transplantations performed with donor lungs reconditioned ex vivo that had been deemed unsuitable for transplantation by the Scandiatransplant, Eurotransplant, and UK Transplant organizations because the arterial oxygen pressure was less than 40 kPa. The three-month survival of patients undergoing transplant with these lungs was 100%. One patient died due to sepsis after 95 days, and one due to rejection after 9 months. Four recipients are still alive and well 24 months after transplantation, with no signs of bronchiolitis obliterans syndrome. The donor lungs were reconditioned ex vivo in an extracorporeal membrane oxygenation circuit using STEEN solution mixed with erythrocytes, to dehydrate edematous lung tissue. Functional evaluation was performed with deoxygenated perfusate at different inspired fractions of oxygen. The arterial oxygen pressure was significantly improved in this model. This ex vivo evaluation model is thus a valuable addition to the armamentarium in increasing the number of acceptable lungs in a donor population with inferior arterial oxygen pressure values, thereby, increasing the lung donor pool for transplantation. In the following paper we present our clinical experience from the first six patients in the world. We also present the technique we used in detail with flowchart

How to Recondition Ex Vivo Initially Rejected Donor Lungs for Clinical Transplantation: Clinical Experience from Lund University Hospital

A major problem in clinical lung transplantation is the shortage of donor lungs. Only about 20% of donor lungs are accepted for transplantation. We have recently reported the results of the first six double lung transplantations performed with donor lungs reconditioned ex vivo that had been deemed unsuitable for transplantation by the Scandiatransplant, Eurotransplant, and UK Transplant organizations because the arterial oxygen pressure was less than 40 kPa. The three-month survival of patients undergoing transplant with these lungs was 100%. One patient died due to sepsis after 95 days, and one due to rejection after 9 months. Four recipients are still alive and well 24 months after transplantation, with no signs of bronchiolitis obliterans syndrome. The donor lungs were reconditioned ex vivo in an extracorporeal membrane oxygenation circuit using STEEN solution mixed with erythrocytes, to dehydrate edematous lung tissue. Functional evaluation was performed with deoxygenated perfusate at different inspired fractions of oxygen. The arterial oxygen pressure was significantly improved in this model. This ex vivo evaluation model is thus a valuable addition to the armamentarium in increasing the number of acceptable lungs in a donor population with inferior arterial oxygen pressure values, thereby, increasing the lung donor pool for transplantation. In the following paper we present our clinical experience from the first six patients in the world. We also present the technique we used in detail with flowchart

Student assessment of teaching as a source of information about aspects of teaching quality in multiple subject domains: an application of multilevel bifactor structural equation modeling

Research on educational effectiveness most often uses student assessments of classroom instruction for measuring aspects of teaching quality. Given that crucial inferences on the success of education are based on these assessments, it is essential to ensure that they provide valid indicators. In this study, we illustrate the application of an innovative application of a multilevel bifactor structural equation model (ML-BFSEM) to examine the validity of student assessments. Analyzing a large-scale data set of 12,077 fourth-grade students in three countries (Finland, Norway, and Sweden), we find that (i) three aspects of teaching quality and subject domain factors can be established; (ii) metric and scalar invariance could be established for the ML-BFSEM approach across countries; and (iii) significant relations between students’ assessments of how easy the teacher is to understand and achievement in all subjects exist. In support of substantive research, we demonstrate a methodological approach for representing the complex nature of student assessments of teaching quality. We finally encourage substantive and methodological researchers to advance the ML-BFSEM

Vacuum-Assisted Closure Therapy - A new Treatment Modality in Poststernotomy Mediastinitis

Poststernotomy mediastinitis is a devastating complication associated with median sternotomy, which occurs mainly after cardiac surgery. The optimal treatment is still controversial. The aim was to develop, describe and evaluate a surgical procedure consisting of vacuum-assisted closure (VAC) in combination with delayed primary closure in patients with mediastinitis. A porcine sternotomy wound model was created to investigate if super-physiological negative pressures affect peristernal tissues and respiratory parameters. It was concluded that early VAC therapy followed by delayed primary closure, guided by the plasma C-reactive protein level is a reliable and easily applied new strategy in patients with poststernotomy mediastinitis. This modified therapy is a safe and reproducible option to bridge patients with deep wound infection to complete healing with low morbidity and mortality rates. Reconstruction of the preserved sternum was achieved in forty patients without the use of muscle or omental flap surgery. Furthermore, vacuum-assisted sternal closure induces a change in microvascular blood flow that is dependent on the pressure applied, the distance from the wound edge, and tissue type. Wound fluid oxygenation and lactate levels increased in vacuum-exposed tissues. This may be a key to further understanding of the mechanisms by which VAC therapy enhances wound vascularity and formation of granulation tissue. Additionally, the findings following sternal VAC application suggest that respiratory physiology and oxygenation were not affected, when pressures ranging from -50 mmHg to -175 mmHg were compared

Early Surgical Experience of Right Ventricular Outflow Reconstruction with the RVOT Elan Conduit in Adults and Adolescents with Congenital Heart Disease.

Several types of valves and valved conduits have been developed for right ventricular outflow tract reconstruction and yet no one has provided prolonged satisfactory hemodynamic performance. The RVOT Elan is a bioprosthetic heart valve conduit constructed from a vascular graft and a porcine stentless valve indicated specifically for right ventricular outflow tract reconstruction. The present study aimed to evaluate the early clinical and hemodynamic results following implantation of the RVOT Elan in adults and adolescents with congenitally corrected right ventricular outflow tract anomalies requiring reintervention