Experimental And Clinical Study On Lung Auto-transplantation

Part I: Establishment of a porcine model of lobar lung auto-transplantation and the effects of different pulmonary infusion on the transplanted lung injuryObjective:To duplicate the swine model of left single lung auto-transplantation; to compare the difference of pulmonary function and other parameters within different pulmonary artery perfusion in this model.Methods:Eighteen healthy local pigs were used as experimental animals, the body weight was 49.7±3.0 kg. The animals were divided into three groups randomly (n = 6 in each group); control group (group A), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe) without pulmonary artery perfusion; Normothermic heparin group (group B), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe) and pulmonary artery infused with heparin in normal temperature; Cold EC group (group C), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe) and with cold Euro-Collins pulmonary artery perfusion. The blood sample and lung tissues were collected at baseline, 0.5, 1, 2, and 4 hours after lobar lung auto-transplantation respectively. The indices were determined as follows: the oxygen pressure of pulmonary vein blood (PvO2), the carbon dioxide pressure of pulmonary vein blood (PvCO2), dynamic lung compliance (Cdyn) and mean pulmonary artery pressure (mPAP) of the transplanted lobar lung, the malondialdchyde (MDA) and myeloperoxidase (MPO) content of the transplanted lung tissue, and the lung water content of the transplanted lung tissue. The lung tissue wet/dry ratio (W/D) was analyzed simultaneously. At 4 h after lung (or lobar lung) auto-transplantation, the pulmonary grafts were sampled for histological examination and ultra-structure observation under the electronic microscopes. Results:1,There were no statistical significance of the PvO2, PvCO2 and Cdyn levels within the three groups at the time-points of the baseline, 0.5, 1, or 2 hours after transplantation. The levels of PvO2 and Cdyn decreased after reperfusion while PvCO2 increased in all groups. Compared with the baseline, PvO2 levels at time-point of 2 and 4 hours post-operatively and PvCO2 levels at time-point of 4 hours post-operatively, Cdyn levels at time-point of 4 hours post-operatively were significantly different in group A (P<0.05). Compared to group A, 4 hours post-operative PvO2, PvCO2 and Cdyn levels have significant difference in group B and C (P<0.05).2,At the time-points of the baseline, 1, 2, and 4 hours after auto-transplantation, mPAP levels have no difference within the three groups. It increased immediately after surgery and decreased thereafter. At 0.5 hour after transplantation, the mPAP level was significantly elevated in group A compared with the baseline (P<0.05). However, the levels in groups B and C were markedly retarded compared with group A (P<0.05).3,At the time-points of baseline, 0.5, 1, and 2 hours after transplantation, there were no statistical significance in all groups with respect to MDA and MPO contents, which elevated immediately after transplantation in all groups. Compared with the baseline, MDA concentrations at 2 and 4 hours post-operatively and MPO contents at 1, 2, and 4 hours post-operatively were significantly increased in group A. Compared to the baseline, 4 hours post-operative MDA and MPO contents were significantly elevated?? in group B and C (P<0.05). Compared with group A, MDA and MPO levels at 4 hours after operation were significantly decreased in group B and C (P<0.05).4,The lung tissue W/D ratio, ultra-structure and structure within the three groups at the baseline were comparable. The W/D ratio elevated immediately after reperfusion in all groups. When compared with the baseline, W/D ratio were remarkably raised at 1, 2, and 4 hours after transplantation in group A (P<0.05) and at 2 and 4 hours after transplantation in group B and C (P<0.01). Moreover, as compared with group A, both normothermic heparin and cold EC perfusion decrease the W/D ratio (P<0.05), as well as retarding the injury under electronic and light microscopy in group B and C at 4 hours after transplantation. Conclusions:1. It is practicable of the establishment of porcine model of lobar lung auto-transplantation. This model has satisfactory stability and repeatability. Consequently, it is an ideal experimental animal model for the evaluation of the pulmonary function and other parameters after lobar lung transplantation.2. Pulmonary artery perfusion either with normothermic heparin or cold Euro-Collins solution can preserve the transplanted lobar lung structure, reduce the ischemia-reperfusion injury, and maintain the gas exchange function.3. Pulmonary artery infusion with normothermic heparin meets the requirement of lobar lung auto-transplantation.Part II: Warm ischemic time limit of porcine lobar lung auto-transplantationObjective:To observe the change of pulmonary function and other parameters such as structure and oxyradical levels after porcine lobar lung auto-transplantation between different pig left pulmonary ischemic periods; to determine the largest warm ischemic time limit of lobar lung transplantation and explore the possible involved mechanisms.Methods:hirty-six healthy local pigs were used as experimental animals, and the body weight was 49.5±2.2 kg. The animals were divided into six groups randomly (n=6 in each group); Normothermic heparin without ischemia group (group B), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe) without additional pulmonary circulation occlusion and pulmonary artery infused with heparin in normal temperature; Normothermic heparin with 60 min ischemic period group (group B1), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe), pulmonary artery infused with heparin in normal temperature and additional 60 min pulmonary circulation occlusion; Normothermic heparin with 120 min ischemic period group (group B2), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe), pulmonary artery infused with heparin in normal temperature and additional 120 min pulmonary circulation occlusion; Low temperature EC without ischemia group (group C), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe) without additional pulmonary circulation occlusion and with cold Euro-Collins pulmonary artery perfusion. Low temperature EC with 60 min ischemic period group (group C1, ), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe) with cold Euro-Collins pulmonary artery perfusion and 60 min pulmonary circulation occlusion; Low temperature EC with 120 min ischemic period group (group C2), received left pneumonectomy and lobar lung auto-transplantation (left lower lobe) with cold Euro-Collins pulmonary artery perfusion and 120 min pulmonary circulation occlusion. The blood sample and lung tissues were collected at baseline, 0.5, 1, 2, 4 hours after lobar lung auto-transplantation. The indices were determined as follows: the oxygen pressure of pulmonary vein blood (PvO2), the carbon dioxide pressure of pulmonary vein blood (PvCO2), dynamic lung compliance (Cdyn) and mean pulmonary artery pressure (mPAP) of the transplanted lobar lung, the malondialdchyde (MDA) and myeloperoxidase (MPO) content of the transplanted lung tissue, and the lung water content of the transplanted lung tissue were detected. The lung tissue wet/dry ratio (W/D) was analyzed simultaneously. At 4 hours after lung (or lobar lung) auto-transplantation, the transplanted lung tissue was sampled for histological examination and ultra-structure observation under the electronic microscopes. Additionally, we measured the serum levels of tumor necrosis factor-alpha (TNF-α) and matrix metalloproteinase-9 (MMP-9) and lung tissue matrix metalloproteinase concentration at 4 hours after the operation.Results:1,There were no difference of the PvO2, PvCO2 and Cdyn levels within the six groups at the time-points of the baseline, 0.5, 1 and 2 hours after transplantation. The levels of PvO2 and Cdyn decreased after reperfusion while PvCO2 increased in all groups. Compared with no additional ischemia group, PvO2 level at 2 and 4 hours post-operatively, PvCO2 level and Cdyn level at 4 hours post-operatively were significantly different in group B2 (P<0.05). Compared to the level of group C2, 4 h post-operative PvO2, PvCO2 and Cdyn levels have significant difference in group B2 (P<0.05).2,At the time-point of the baseline, and 1 h, 2 h, 4 h after auto-transplantation, there was no difference of the mPAP level within the six group. It increased immediately after surgery and decreased thereafter. Compared to the levels of no additional ischemia group, 0.5 h post-operative mPAP level was significantly elevated in group B2 (P<0.05). At time-point of 0.5 h following operation, mPAP level have significant increased in group B2 comparing the level of group C2 (P<0.05).3,MDA and MPO contents was no difference within the six groups at the time-point of the baseline and 0.5 h after auto-transplantation, which rise immediately after transplantation in all groups. Compared to the levels of no additional ischemia group, 4 h post-operative MDA and MPO levels were significantly increasing in group B2. At time-point of 4 h post-operatively, MDA and MPO contents were significant high in group B2 compared with the levels of group C2 (P<0.05).4,The lung tissue W/D ratio, ultra-structure and structure within the three groups at the baseline were comparable. The W/D ratio elevated immediately after reperfusion in all groups. Compared to the levels of no additional ischemia group, W/D ratio at the time-point of 1 h, 2 h, and 4 h post-operatively were significantly increased in group B2 (P<0.05). At the time-point of 2 h and 4 h after surgery, W/D ratio were significant different in group B2 compared to the levels of group C2 (P<0.05). Compared to the level of group A, 4 h post-operative W/D ratios have significant difference in group B and C (P<0.05). The 4 h post-operative ultra-structure and light microscope score were significantly different in group B2 compared with no additional ischemia group.5,Compared with the levels of no additional ischemia group, serum TNF-αand MMP-9 levels and MMP-9 positive scores were significantly elevated in group B2 (P<0.01). Serum TNF-αand MMP-9 levels and MMP-9 positive scores were significantly different in group B2 compared to the levels of group C2 (P<0.01).Conclusions:1,Additional ischemia period before lobar auto-transplantation either with normothermic heparin or cold Euro-Collins solution will damage the transplanted lobar lung structure, induce the ischemia-reperfusion injury, increase the oxyradical level, and impair the gas exchange function.2,At least less than 60 min additional ischemic period, pulmonary artery infusion with normothermic heparin meets the requirement of porcine lobar lung auto-transplantation. If the additional ischemia period more than 60 min but less than 120 min, pulmonary artery infusion with cold Euro-Collins is recommended.3,Compared with pulmonary infusion with the normothermic heparin, pulmonary artery infusion with cold Euro-Collins might be better, and the involved mechanism is possibly associated with suppressing the elevation of serum TNF-αand MMP-9 and tissue MMP-9 more effectively.Part III: Lung auto-transplantation technique in the treatment for central lung cancer of upper lobeObjective:To assess the feasibility and benefit of lung auto-transplantation technique in the treatment for central lung cancer of upper lobe which could not tolerate pneumotomy. To compare the perioperative mortality (within 30 days), major complication morbidity, survival time, pulmonary function and life quality within the patients who underwent pneumonectomy, sleeve lobectomy and auto-transplantation. To obtain more evidence and experience for the clinical application of the lung auto-transplantation technique.Method:Seven patients underwent double - sleeve right upper and middle bilobectomy from Aug 2000 to Aug 2006. Because the length of resected bronchus or pulmonary artery was too long to perform a tension - free anastomoses, we had to transect and transplant the lower lobar vein to proximal stump of the upper lobar vein. Meanwhile, 41 patients underwent sleeve lobectomy and 194 patients underwent pneumonectomy. To compare the peri-operative mortality (within 30 days), major complication morbidity (i.e. anastomotic fistulas), survival time, pulmonary function and life quality between the patients who underwent pneumonectomy, sleeve lobectomy and auto-transplantation.Result:Until Aug. 2006, in the auto-transplantation group, five patients had been alive tumor free for 2-73 months with good quality of life, and the estimated median live time was 24 months. One patient was performed resection of the replanted lung because of pulmonary vein thrombus on 2nd day after transplantation, and died of respiratory failure caused by pulmonary relapse on 15th month postoperatively. Another patient died of brain metastases 31 months postoperatively. The predicted median survival time of all patients was 71 months. The incidence of bronchial anastomotic stoma fistulas after pneumonectomy and sleeve lobectomy was 3.6% (7 of 194 patients) and 2.4% (1 of 41 patients) respectively. The incidence of early mortality was 2.6% (5 of 194 patients) in pneumonectomy group. The estimated median live time after pneumonectomy was 30 months and after sleeve lobectomy, 36 months. The pulmonary function and life quality was significantly different within groups (p<0.05).Conclusion:Lung auto-transplantation is an alternative and beneficial technique with pulmonary preservation for patient with stage III central lung cancer of upper lobe when his pulmonary reserve is too low to afford pneumonectomy. Compare with people undergoing pneunonectomy, patients undergoing lobar auto-transplantation have better pulmonary function and life quality, lower peri-operative morbidity and mortality, and longer survival time.