Ischemia-reperfusion injury with a model of porcine whole-blood ex-vivo lung perfusion

Introduction Our objective was to model Ischemia-Reperfusion (IR) injuries by ex-vivo perfusion of porcine lungs with whole blood containing the inflammatory cells. Methods Lungs and whole blood were collected from 12 pigs and submitted to cold ischemia time (CIT) of 1 or 18 h. The lungs were then ventilated and perfused for 6 h at 37°C using donor whole blood. Pulmonary pressure was 20 mmHg. Results Compared to the short CIT group, the long CIT group had a lower maximum perfusion flow rate (mean difference in % cardiac output, −39%; 95% CI, −66 to −12; P = 0.005) and higher pulmonary vascular resistance (mean difference, 1,077 dyne·s·cm − ⁵; 95% CI, 685–1,469; P < 0.001). Neutrophils decreased more in the long CIT group (mean difference, −744.02 cells/mm 3 ; 95% CI, −1,343.11 to −144.92; P = 0.017), suggesting sequestration in the lung parenchyma. Interleukin-6 and −8 levels after 6 h were significantly higher in the long CIT group (mean differences, 1.1 pg/ml; 95% CI, 0.39–1.8; P = 0.003; and 29.31 pg/ml; 95%CI, 16.00–42.61; P < 0.001; respectively). Progressive microvasculopathy resulting in lymphangiectasia and peribronchovascular inflammatory infiltrates were seen in both groups. Conclusion After 18 h of CIT, ex-vivo whole-blood perfusion for 6 h replicated features of IR injuries.