Expeimental Study on Pulmonary Function and Lung Growth after Living-Donor Lobar Lung Transplantation

实验1：为了解决供体短缺的问题，活体供体大叶肺移植取得了令人满意的结果。使用小的移植物是潜在的问题，因为它可能导致肺动脉高压，导致肺水肿。本研究的目的是评估小移植物对早期肺功能的影响，并确定可接受的大小差异的预测因子。17对不同供体/受体（D/R）大小的杂种狗。测量体重、身高、胸围和肺重作为尺寸参数。右中叶、下叶和心叶作为受者的右肺植入，左下叶作为左肺植入，不使用体外循环。再灌注后6小时测定受体肺功能。D/R体重比与1 h平均肺动脉压呈显著负相关（R =-0.594; p=…More 0.025）。D/R体重比与6 h动脉血氧压（Pa02）有显著相关性（R =0.704; p=0.007）。其他三个尺寸参数与术后肺功能无显著相关性。8例D/R体重比bbb1.2的患者均存活6小时，6小时时PaO2均超过500 mmHg。D/R重量比是犬活体大叶肺移植模型早期肺功能的重要预测指标。实验2：对于婴幼儿，器官移植受到供体和受体大小差异的限制。为了解决这个问题，使用来自活体供体的超大尺寸移植物可能会扩大供体池。本实验研究的目的是评估过大的移植物对早期肺功能的影响，并确定一个可接受的大小差异的指标。对体重不匹配的犬进行了14例双侧大叶肺同种异体移植手术，无需体外循环。实验动物分为两组：ⅰ组（n=7），供受体肺容积比< 2.85；II组（n=7），供受体肺容积比> 2.85。分别在闭胸前、闭胸后和取下呼吸机后测量受体的肺功能。II组肺血管阻力和气道压力在闭胸后显著升高（1493±195 dynes sec.cm-5和14.4±0.9 mmHg），而非2784±140 dynes sec。cm-5和23.4±1.2 mmHg, p<0.001)。取下呼吸机后，I组所有受者Pa02 >均为239 mmHg， PaC02 < 76 mmHg， II组所有受者Pa02 <116 mmHg, PaCO2 >为169 mmHg。除1只犬外，组中供体/受体胸围比均小于1.3。可接受的超大尺寸移植物提供了足够的肺功能，尽管过度超大尺寸移植物在闭胸后会导致肺功能明显受损。胸围提供了一个有用的尺寸匹配标准，当过大的移植物在这个犬实验模型中使用。少

Experiment 1: In an effort to address the donor shortage issue, living-donor lobar lung transplants have been performed with satisfactory results. The use of small grafts is potentially problematic because it could cause high pulmonary artery pressure resulting in lung edema. The purpose of this study was to evaluate the effect of small grafts on early pulmonary function and to identify the predictor for acceptable size discrepancy. Seventeen pairs of mongrel dog with various donor/recipient (D/R) sizes were used. Body weight, height, chest circumference and lung weight were measured as size parameters. Right middle, lower and cardiac lobes were implanted as a right lung of the recipient and left lower lobe was implanted as a left lung without using cardiopulmonary bypass. Pulmonary function of the recipient was measured for 6 hours after reperfusion. A significant negative correlation was found between D/R body weight ratio and mean pulmonary artery pressure at one hour (r=-0.594 ; p= … More 0.025). A significant correlation was found between D/R body weight ratio and arterial oxygen tension (Pa02) at 6 hours (r=0.704 ; p=0.007). There was no significant correlation between the other three size parameters and postoperative pulmonary function. All 8 recipients with D/R body weight ratio > 1.2 survived the 6-hour assessment period and their PaO2 exceeded 500 mmHg at 6 hours. D/R weight ratio is an important predictor of early pulmonary function in a canine living-donor lobar lung transplant model.Experiment 2 : For infants and small children, organ transplantation is limited by the size discrepancy between donor and recipient. To address this problem, the use of over-sized grafts from living-related donors could potentially expand the donor pool. The aim of this experimental study was to evaluate the effect of over-sized grafts on early pulmonary function and to identify an indicator for an acceptable size discrepancy. Fourteen bilateral lobar lung allotransplant operations were performed without cardiopulmonary bypass in weight mis-matched pairs of dogs. Animals were divided into two groups : Group I (n=7), Donor/Recipient lung volume ratio < 2.85 ; Group II (n=7), Donor/Recipient lung volume ratio > 2.85. Pulmonary function of the recipient was measured before chest closure, after chest closure, and after the ventilator was removed. Pulmonary vascular resistance and airway pressure significantly increased in group II after, chest closure (1493±195 dynes sec.cm-5 and 14.4± 0.9 mmHg versus 2784±140 dynes.sec.cm-5 and 23.4±1.2 mmHg, p<0.001). After the ventilator was removed, all recipients in group I showed Pa02 > 239 mmHg and PaC02 < 76 mmHg, whereas all recipients in group II showed Pa02 <116 mmHg and PaCO2 > 169 mmHg. The Donor/recipient chest circumference ratio was less than 1.3 in all but one dog in group I. Acceptable over-sized grafts provide adequate pulmonary function, although excessively over-sized grafts cause significant impairment in pulmonary function after the chest closure. Chest circumference provides a useful size match criteria when over-sized grafts are used in this canine experimental model. Less