A Short Period of Ventilation without Perfusion Seems to Reduce Atelectasis without Harming the Lungs duringEx VivoLung Perfusion

To evaluate the lung function of donors after circulatory deaths (DCDs),ex vivolung perfusion (EVLP) has been shown to be a valuable method. We present modified EVLP where lung atelectasis is removed, while the lung perfusion is temporarily shut down. Twelve pigs were randomized into two groups: modified EVLP and conventional EVLP. When the lungs had reached 37°C in the EVLP circuit, lung perfusion was temporarily shut down in the modified EVLP group, and positive end-expiratory pressure (PEEP) was increased to 10 cm H2O for 10 minutes. In the conventional EVLP group, PEEP was increased to 10 cm H2O for 10 minutes with unchanged lung perfusion. In the modified EVLP group, the arterial oxygen partial pressure (PaO2) was 18.5 ± 7.0 kPa before and 64.5 ± 6.0 kPa after the maneuver (P<0.001). In the conventional EVLP group, the PaO2was 16.8 ± 3.1 kPa and 46.8 ± 2.7 kPa after the maneuver (P<0.01;P<0.01). In the modified EVLP group, the pulmonary graft weight was unchanged, while in the conventional EVLP group, the pulmonary graft weight was significantly increased. Modified EVLP with normoventilation of the lungs without ongoing lung perfusion for 10 minutes may eliminate atelectasis almost completely without harming the lungs.

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A method for translational rat ex vivo lung perfusion experimentation

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00256.2019 ◽

2020 ◽

Vol 319 (1) ◽

pp. L61-L70

Author(s):

Akihiro Ohsumi ◽

Takashi Kanou ◽

Aadil Ali ◽

Zehong Guan ◽

David M. Hwang ◽

...

Keyword(s):

Lung Function ◽

Ex Vivo ◽

Left Lung ◽

Lung Compliance ◽

Lung Perfusion ◽

Arterial Oxygen ◽

Large Animal ◽

Ex Vivo Lung Perfusion ◽

Ischemic Time ◽

Cold Ischemic Time

The application of ex vivo lung perfusion (EVLP) has significantly increased the successful clinical use of marginal donor lungs. While large animal EVLP models exist to test new strategies to improve organ repair, there is currently no rat EVLP model capable of maintaining long-term lung viability. Here, we describe a new rat EVLP model that addresses this need, while enabling the study of lung injury due to cold ischemic time (CIT). The technique involves perfusing and ventilating male Lewis rat donor lungs for 4 h before transplanting the left lung into a recipient rat and then evaluating lung function 2 h after reperfusion. To test injury within this model, lungs were divided into groups and exposed to different CITs (i.e., 20 min, 6 h, 12 h, 18 h and 24 h). Experiments involving the 24-h-CIT group were prematurely terminated due to the development of severe edema. For the other groups, no differences in the ratio of arterial oxygen partial pressure to fractional inspired oxygen ([Formula: see text]/[Formula: see text]) were observed during EVLP; however, lung compliance decreased over time in the 18-h group ( P = 0.012) and the [Formula: see text]/[Formula: see text] of the blood from the left pulmonary vein 2 h after transplantation was lower compared with 20-min-CIT group ( P = 0.0062). This new model maintained stable lung function during 4-h EVLP and after transplantation when exposed to up to 12 h of CIT.

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Targeting Glucose Metabolism During Ex vivo Lung Perfusion Improves Lung Preservation and Post Transplant Lung Function

The Journal of Heart and Lung Transplantation ◽

10.1016/j.healun.2018.01.299 ◽

2018 ◽

Vol 37 (4) ◽

pp. S125

Author(s):

K. Noda ◽

S. Tane ◽

J. D'Cunha ◽

J.D. Luketich ◽

N. Shigemura

Keyword(s):

Glucose Metabolism ◽

Lung Function ◽

Ex Vivo ◽

Lung Perfusion ◽

Ex Vivo Lung Perfusion ◽

Lung Preservation ◽

Post Transplant

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Temperature Controlled and Monitored Ex Vivo Lung Perfusion System for Research and Training Purposes

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2019-0074 ◽

2019 ◽

Vol 5 (1) ◽

pp. 293-295

Author(s):

Christina Pongratz ◽

Jens Ziegle ◽

Axel Boese ◽

Michael Friebe ◽

Helena Linge ◽

...

Keyword(s):

Storage Temperature ◽

Ex Vivo ◽

Culture Conditions ◽

Lung Perfusion ◽

Tissue Storage ◽

Ex Vivo Lung Perfusion ◽

Device Development ◽

Preservation Method ◽

Normothermic Perfusion ◽

Short Period

AbstractEx vivo lung perfusion (EVLP) is a preservation method for donor lungs, which keep lungs viable in a physiological environment outside of a body for a short period of time. EVLP is established clinically for lung transplantation. Experimental applications for EVLP are e.g. lung cancer research or medical device development and testing. For preservation, a lung is ventilated artificially in an organ chamber and perfused antegrade through the pulmonary artery. Here we introduce a thermoregulation system for an experimental EVLP system to be used for translational research approaches as well as for training medical staff. To implement physiological culture conditions that are a prerequisite for lung preservation and tissue homeostasis, a thermoregulation is needed to rewarm the explanted lung tissue (storage temperature 4°C). Technically, the EVLP system must be thermally insulated, so loss of caloric is avoided. For monitoring, temperature sensors are integrated within the lung, in the organ chamber and in the afferent perfusate tube, whereby the measured values determine the thermoregulation. Initial tests using thermal packs (cooled to 4-6°C) placed on a heating mat, as a part of the perfusion circuit, showed that the perfusate temperature falls to 34°C, but restores after approximately 60 minutes (36.5°C), whereby the thermal pack is warmed. With this setup longer perfusion times should be obtained rather than without thermoregulation due to normothermic perfusion of the lung.

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