Avaliação e recondicionamento pulmonar ex vivo

Abstract

Objective: Only about 15% of the potential candidates for lung donation are considered suitable for transplantation. A new method for ex vivo lung perfusion (EVLP) has been developed and can be used for evaluation and reconditioning of "marginal" and unacceptable lungs. This is a report of functional evaluation experience with ex vivo perfusion of twelve donor lungs deemed unacceptable in São Paulo, Brazil.Methods: After harvesting, the lungs are perfused ex vivo with Steen Solution, an extra-cellular solution with high colloid osmotic pressure. A membrane oxygenator connected to the circuit receives gas from a mixture of nitrogen and carbon dioxide and maintains a normal mixed venous blood gas level in the perfusate. The lungs are gradually rewarmed, reperfused and ventilated. They are evaluated through analyses of oxygenation capacity, pulmonary vascular resistance (PVR), lung compliance (LC).Results: The arterial oxygen pressure (with inspired oxygen fractions of 100%) increased from a mean of 193.3 mmHg in the organ donor at the referring hospital to a mean of 495.3 mmHg during the ex vivo evaluation. After 1 hour of EVLP, mean PVR was 737.3 dynes/sec/cm 5 , and mean LC was 42.2 ml/cmH 2 O. Conclusions:The ex vivo evaluation model can improve oxygenation capacity of "marginal" lungs rejected for transplantation. It has a great potential to increase lung donor availability and, possibly, to reduce the waiting time on the list. Descriptors: Lung transplantation. Organ preservation. Lung injury.Resumo Objetivo: Apenas 15% dos pulmões doados são aproveitados para transplante. Um novo método de Perfusão Pulmonar Ex Vivo (PPEV) foi desenvolvido e pode ser usado para avaliação e recondicionamento de pulmões "marginais" e rejeitados para o transplante. Esse trabalho relata nossa experiência com a avaliação funcional da PPEV.Métodos: Foram estudados pulmões de 12 doadores considerados inapropriados para transplante pulmonar. Após a captação, os pulmões são perfundidos ex vivo com Steen Solution, uma solução de composição eletrolítica extracelular com alta pressão coloidosmótica. Um oxigenador de membrana ligado ao circuito recebe uma mistura gasosa (nitrogênio e dióxido de carbono) e Bras Cir Cardiovasc 2010; 25(4): 441-446 "desoxigena" o perfusato, mantendo uma concentração de gases semelhante a do sangue venoso. Os pulmões são gradualmente aquecidos, perfundidos e ventilados. A avaliação dos órgãos é feita por gasometrias e medidas como a resistência vascular pulmonar (RVP) e complacência pulmonar (CP). 442 PÊGO-FERNANDES, PM ET AL -Ex vivo lung evaluation and reconditioning RevResultados: A PaO 2 (FiO 2 100%) passou de um valor médio de 193,3 mmHg no doador para 495,3 mmHg durante a PPEV. Após uma hora de PPEV, a RVP média era de 737,3 dinas/seg/ cm 5 e a CP era de 42,2 ml/cmH 2 O.Conclusões: O modelo de avaliação pulmonar ex vivo pode melhorar a capacidade de oxigenação de pulmões "marginais" inicialmente rejeitados para transplante. Isso denota um grande potencial do método para aumentar a disponibili...

A survey of recently published cardiovascular, hematological and pneumological original articles in the Brazilian scientific press

“…Navarro et al101 evaluated the biological and functional behavior of decellularized pulmonary homografts (Decell-H), treated by a sodium dodecil sulfate solution (0.1%) and found that in their experimental model, the Decell-H behaved as an excellent valve substitute. Pego-Fernandes et al102 report on the functional evaluation experience with ex vivo perfusion of twelve donor lungs deemed unacceptable in Sao Paulo, Brazil. They claim that ex vivo evaluation model can improve oxygenation capacity of “marginal” lungs rejected for transplantation.…”

Ex vivo lung perfusion in Brazil

“…( 11 ) In an experimental study conducted by our team, we found a significant improvement in arterial blood gas values after 1 h of EVLP. ( 12 , 13 ) However, we highlight some methodological differences relative to the present study, such as the use of an FiO 2 of 100% throughout perfusion and the use of an open left atrium.…”

Extracorporeal membrane oxygenation as a bridge to pulmonary transplantation in Brazil: Are we ready to embark upon this new age?

“…The number of patients in need of this procedure and their disease severity has increased in recent years; however, the reduced number of lung donors has resulted in a high mortality rate for patients on the waiting list 2. Some of these patients with exacerbations of severe chronic pulmonary disease can be temporarily supported by extracorporeal membrane oxygenation systems, prolonging life until a donor lung is available for transplantation 3.…”