OBJECTIVETo study effects of pulmonary artery perfusion with hypothermic solution on the apoptosis of lung parenchymal cells during cardiopulmonary bypass.

METHODSForty children with tetralogy of Fallot were divided into control group (n = 20) and protective group (n = 20). The patients in control group were performed using routine approaches. Patients' pulmonary artery were infused with 4 degrees C protective solution during cardiopulmonary bypass in protective group. Lung biopsy specimens were obtained after operations in order to study the apoptosis of lung parenchymal cells using tunnel techniques. At same time, patients' pulmonary functions and clinic index were monitored.

RESULTSThe rate of apoptosis cells of lung parenchymal cells was (18 +/- 7)% in control group, whereas (10 +/- 2)% in protective group. There was significant difference between both groups (t = -2.95, P < 0.05). Index O(2) in protective group was higher than that in control group at 0, 6 and 12 hours after operations [(492 +/- 172), (444 +/- 104), (489 +/- 58) mm Hg versus (369 +/- 126), (347 +/- 107), (340 +/- 119) mm Hg, t = 2.59, P < 0.05; t = 2.88, P < 0.01; t = 5.06, P < 0.01, respectively)]. The time of mechanical ventilation was significantly shorter in protective group than in control group [(15 +/- 11) hours versus (26 +/- 15) hours, t = -2.76, P < 0.01].

CONCLUSIONPulmonary artery perfusion with hypothermic solution can inhibit the apoptosis of lung parenchymal cells and relieve cardiopulmonary bypass-induced lung injury.