Ex vivo reconditioning of marginal donor lungs injured by acid aspiration.
BACKGROUND
Injured lungs due to gastric acid aspiration may be rejected for transplantation because of the possibility of early graft dysfunction. We hypothesized that diluted surfactant administration during ex vivo perfusion would recondition the lungs injured by acid aspiration and permit their use as suitable grafts for transplantation.


METHODS
Using a pig model, lung injury was induced with 5-ml/kg administration of a betaine-HCl/pepsin mixture via a flexible bronchoscope. After injury, animals were randomly assigned to three study groups (n = 6/group): saline lavage during ex vivo perfusion (control); surfactant lavage ex vivo (SL-Exvivo); and surfactant lavage before harvest (SL-Pre); and a normal group (n = 4), with no lung injury. Cold storage time was 3 hours. A volume of 10 ml/kg (4 mg/ml, 40 mg/kg) surfactant (Curosurf) was used for lavage. Bronchoalveolar lavage (BAL) was performed before and after injury and at the end of the experiment. Protein and neutrophil percentage in BAL were assessed. Hemodynamic and aerodynamic parameters were measured every 30 minutes during a 2-hour observation period.


RESULTS
An approximately 50% decrease in Pao(2) was observed in all animals after injury. Ex vivo surfactant lavage resulted in lower pulmonary vascular resistance, lower oxygenation index and higher Pao(2)/Fio(2) ratio compared with the control group (p = 0.001, p = 0.0001 and p = 0.0001, respectively, according to analysis of variance for repeated measures). Wet-to-dry weight ratio was lower in the SL-Exvivo group compared with the control group (p = 0.015). BAL neutrophil percent at the end of the experiment differed significantly between control and all other groups (p < 0.05).


CONCLUSIONS
Diluted surfactant lavage during ex vivo perfusion improves graft function of lungs injured by gastric acid aspiration.
Inci
Ilhan
I
Division of Thoracic Surgery, University Hospital, University of Zurich, Switzerland.
Ampollini
Luca
L
Arni
Stephan
S
Jungraithmayr
Wolfgang
W
Inci
Demet
D
Hillinger
Sven
S
Leskosek
Boris
B
Vogt
Peter
P
Weder
Walter
W
D000818:Animals; D001622:Betaine / Q000633:toxicity; D005744:Gastric Acid / Q000378:metabolism*; D006801:Humans; D006851:Hydrochloric Acid / Q000633:toxicity; D001239:Inhalation; D008168:Lung / Q000502:physiology; D055370:Lung Injury / Q000139:chemically induced* / Q000209:etiology; D016040:Lung Transplantation / Q000502:physiology*; D023421:Models, Animal; D010100:Oxygen / Q000097:blood; D010434:Pepsin A / Q000633:toxicity; D013552:Swine; D014019:Tissue Donors / Q000706:statistics & numerical data*; D019172:Transplantation Conditioning / Q000379:methods*; D014655:Vascular Resistance / Q000502:physiology
D001622:Betaine; D010434:Pepsin A; D006851:Hydrochloric Acid; D010100:Oxygen