Exogenous surfactant improves survival and surfactant function in ischaemia-reperfusion injury in minipigs

Reperfusion injury is the major cause of early morbidity and mortality after lung transplantation. This complication has been experimentally linked to dysfunction of pulmonary surfactant. Therefore, the hypothesis that reperfusion injury might be preventable by exogenous surfactant treatment was tested. Left lungs of minipigs were exposed to 120 min of ischaemia, and the lungs were then reperfused for up to 7 h. Animals were divided into a control group and a surfactant group (n=5 each). The surfactant group received 50 mg x kg(-1) Alveofact intrabronchially via a bronchoscope at the beginning of the ischaemic period. Bronchoalveolar lavage was performed at baseline before ischaemia and 90 min after reperfusion. Surfactant treatment significantly improved short-term survival. Pulmonary vascular resistance increased markedly in control animals leading to right heart failure and death within 3 h after reperfusion whereas the surfactant-treated animals survived the 7 h observation period. After reperfusion, alveolar accumulation of neutrophils and exuded proteins was present in both groups to the same extent. Surfactant activity after reperfusion deteriorated markedly in the control group but was preserved in the surfactant group. In conclusion, early surfactant treatment alleviates the deterioration of surfactant function and improves survival in this minipig model of ischaemia-reperfusion injury.