ABSTRACT
INTRODUCTION: Pulmonary thromboendarterectomy (PTE) is a surgical procedure which is considered the only effective and potentially curative treatment for chronic thromboembolic pulmonary hypertension (CTEPH). CTEPH is a rare outcome from pulmonary emboli and, when left untreated, will result in right ventricular failure and death. METHODS: From June 1999 to November 2003, 40 of these procedures were performed in our institution. Emphasis is placed on multidisciplinarity and cooperation between different medical and surgical disciplines. Perfusion management consists of myocardial and cerebral protection, deep hypothermia with multiple periods of circulatory arrest, reperfusion at hypothermia, hemofiltration and cellsaving techniques. RESULTS: Hemodynamic improvement occurs immediately post operation. Mean pulmonary artery pressure decreased from 50 +/- 11 to 38 +/- 10 mmHg, pulmonary vascular resistance from 1246+482 to 515 +/- 294 dynes s/cm5 and cardiac index increased from 1.54 +/- 0.54 to 2.63 +/- 0.75 L/min per m2. Pump runs had an average duration of 187 +/- 29 min, circulatory arrest time was 29 +/- 11 min and crossclamp time 36 +/- 14 min. Extracorporeal membrane oxygenation can be an ultimate treatment for specific postoperative problems like persistent pulmonary hypertension and/or reperfusion pulmonary edema.
Subject(s)
Endarterectomy , Extracorporeal Circulation , Hypertension, Pulmonary/surgery , Postoperative Complications/prevention & control , Pulmonary Edema/prevention & control , Pulmonary Embolism/surgery , Chronic Disease , Extracorporeal Circulation/methods , Female , Humans , Hypertension, Pulmonary/etiology , Male , Postoperative Complications/etiology , Pulmonary Edema/etiology , Pulmonary Embolism/complications , Retrospective StudiesABSTRACT
If lungs could be retrieved for transplantation after circulatory arrest, the shortage of donors might be significantly alleviated. An important issue in using lungs from these so-called non-heart-beating donors is the development of a technique to assess their quality prior to transplantation without jeopardizing the life of the recipient. In our laboratory we tested the reliability of an ex vivo model for such an evaluation. We used pig lungs from optimal control animals, in casu heart-beating donors. This model enabled us to preserve and evaluate lungs with perfect function up to 24 hours after death. The intermediate assessment is performed in an isolated circuit where the lungs are being ventilated and reperfused via the pulmonary artery (PA) with autologous and haemodiluted blood. Haemodynamic, aerodynamic and oxygenation parameters are measured at 37.5 degrees C and a maximum PA pressure of 20 mmHg. These data were correlated with premortem values. During this ex vivo evaluation, leukocyte depletion plays an important role since neutrophils have been recognized as critical components in the inflammatory cascade, which is responsible for graft dysfunction soon and long after transplantation.
Subject(s)
Leukocytes/cytology , Lung Transplantation , Lung/physiology , Animals , Graft Survival/physiology , Leukocyte Count , Leukocytes/physiology , Lung/blood supply , Models, Animal , Oxygen/metabolism , Oxygen Consumption/physiology , Positive-Pressure Respiration , Pulmonary Alveoli/physiology , Swine , Time Factors , Tissue Donors , Vascular ResistanceABSTRACT
In modern coronary bypass surgery, new objectives have been set based upon a minimal invasive approach: beating heart surgery is the new trend to follow, although this might not be feasible in more complex cases. In these cases, the beating heart could be supported by a mechanical device, preferably a device with minimal invasive features to fit in this new approach. For this purpose, two intravascular blood pumps were developed: the Intracardiac Pump LV for left ventricular support and the Intracardiac pump RV for right ventricular support. (Impella Cardiotechnik, Aachen, Germany) The Impella pumps are rotary blood pumps of the axial flow type and produce 4.2 L/min at physiological pressure differences and a rotational speed of 32,500 rotations/min. These micropumps can widen the indications of beating heart surgery by sustaining hemodynamic stability and protecting the heart from warm ischemia. The current concept is aimed at bridging a procedure. Therefore, the proof of safe duration of usage has not been extended beyond 6 hours. As the pump-flow is based on standard pressure-flow curves for each so-called "performance level" (resulting from in-vitro experiments), an investigation was conducted to compare this relationship in the in-vitro trials with the findings in pump-supported patients undergoing coronary bypass surgery. It could be concluded that the intracardiac pump is efficacious in assisting coronary bypass surgery.
