A porcine model of acute lung injury by instillation of gastric fluid.
BACKGROUND
About 15% of donor lungs are declined because of aspiration contributing to current organ shortage. The aim was to develop a porcine lung injury model by gastric juice (GJ) instillation to study different pretransplant treatment strategies.


METHODS
Pigs (n = 6/group) were anesthetized and monitored. At T0 bronchoalveolar lavage (BAL) was performed followed by instillation of 4 mL/kg GJ or saline solution (SAL). Hemodynamics, aerodynamics and oxygenation were recorded for two hours. Serum samples were collected. At T120 a second BAL was performed. CT scans of explanted, inflated lungs were taken, tissue samples were collected and wet/dry weight ratio (W/D) was calculated. Pepsin and bile acids were measured in BAL. IL-8, CRP and MMP-9 were measured in serum and in BAL.


RESULTS
Oxygenation and lung compliance was lower in [GJ] versus [SAL] (P < 0.01 and P < 0.001, respectively). More consolidation areas were noticed on CT in GJ versus SAL (P < 0.01). Hemorrhage, edema and neutrophil inflammation were seen on histology in [GJ] (P < 0.01, P < 0.001, P < 0.001, respectively). BAL neutrophils, pepsin, bile acids, and IL-8 (P < 0.05) increased in [GJ]. W/D was higher in [GJ] versus SAL (P < 0.001).


CONCLUSIONS
Instillation of GJ in pig lungs caused acute lung injury with impaired oxygenation and increased inflammation in BAL, on histology, and on imaging. This model holds promise to assess the efficacy of a broad range of treatment strategies including ex vivo lung perfusion (EVLP).
Laboratory for Experimental Thoracic Surgery, Katholieke Universiteit Leuven, Leuven, Belgium. caroline.meers@med.kuleuven.be
Caroline M
CM
Meers
Walter
W
De Wever
Eric
E
Verbeken
Veerle
V
Mertens
Shana
S
Wauters
Stéphanie I
SI
De Vleeschauwer
Robin
R
Vos
Bart M
BM
Vanaudenaerde
Geert M
GM
Verleden
Dirk E M
DE
Van Raemdonck
D055371:Acute Lung Injury / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D000403:Airway Resistance; D000818:Animals; D018893:Bronchoalveolar Lavage; D001992:Bronchoalveolar Lavage Fluid; D004195:Disease Models, Animal; D005750:Gastric Juice; D016040:Lung Transplantation; D008297:Male; D011014:Pneumonia / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D011652:Pulmonary Circulation; D011659:Pulmonary Gas Exchange; D011859:Radiography; D053120:Respiratory Aspiration / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D013047:Specific Pathogen-Free Organisms; D013552:Swine; D014019:Tissue Donors