Combined Use of Prostacyclin and Higher Perfusate Temperatures Further Enhances the Superior Lung Preservation by Celsior Solution in the Isolated Rat Lung Thorsten Wittwer, MD, a Thorsten Wahlers, MD, a Antonia Fehrenbach, PhD, a Jan F. Cornelius, a Sebastian Elki, a Matthias Ochs, MD, b Heinz Fehrenbach, PhD, c Johannes Albes, MD, d Axel Haverich, MD, a and Joachim Richter, MD b Background: The poor tolerance of the lung to ischemia and reperfusion (IR) still represents one of the limitations in clinically successful lung transplantation. Modified Euro-Collins (EC) is routinely used in lung preservation, but alternative solutions have been developed for improvement of pulmonary preservation. Celsior is an extracellular solution that has significantly reduced the IR-induced pulmonary damage in animal studies. So far, no extensive experimental studies exist concerning the influence of Celsior on pulmonary gas exchange following IR. Methods: In an extracorporeal rat lung model 10 lungs, each, were preserved with Celsior (CE) and Celsior/prostacyclin (CEPC, 6 g/100 ml) at 4° and 15°C, each, and compared to low-potassium Euro-Collins (EC-40, 40 mmol/liter potassium). After 2 hours of ischemia lungs were reventilated and reperfused using a roller pump. Oxygenation in terms of oxygen partial tension in the left atrial effluent, pulmonary vascular resistance (PVR), peak inspiratory pressure, and wet/dry ratio were monitored for 50 minutes. Furthermore, edema formation was evaluated by light microscopy. Statistical analysis was performed using ANOVA models. Results: Compared to the EC-40 group, oxygenation was increased and amount of edema was reduced in most Celsior-preserved organs ( p 0.032) with exception of the CEPC group at 4°C ( p = 0.06). Additional application of prostacyclin did not have any significant effect on oxygenation in the Celsior group. However, after temperature elevation of the CEPC perfusate to 15°C, a superior partial tension of oxygen was observed ( p 0.023) in contrast to the 4°C groups CE and CEPC. The lowest PVR was found in the CE 4°C group ( p 0.02). Conclusions: Celsior provides better lung preservation than EC-40 solution. Application of prostacyclin at higher perfusate temperatures results in additional functional improvement. In vivo experiments and ultrastructural analysis are warranted for further evaluation of Celsior in lung preservation. J Heart Lung Transplant 1999;18:684–692. From the Division of Cardiothoracic and Vascular Surgery, Medical School Hannover, Carl-Neuberg-Str. 1, 30625, Han- nover. a the Division of Electron Microscopy, Center of Anat- omy, University of Goettingen, Kreuzbergring 36, 37075, Goet- tingen, b the Institute of Pathology, University Clinic, TU Dresden, Fetscherstrasse 74, 01307 Dresden, c and the Division of Cardiothoracic and Vascular Surgery, University Clinic, Hoppe-Seyler-Strasse 3, 72076 Tuebingen, d Germany. Submitted June 30, 1998; accepted November 17, 1998. Reprint requests: Thorsten Wittwer, MD, Division of Cardiotho- racic and Vascular Surgery, Medical School Hannover, Carl- Neuberg-Strasse 1, 30625 Hannover, Germany. Tele: +49-511- 5326580. Fax: +49-511-5325404. E-mail: Th.Wittwer-MD@t- online.de. Copyright © 1999 by the International Society for Heart and Lung Transplantation. 1053-2498/99/$–see front matter PII S1053-2498(98)00061-8 684