大鼠心脏停搏供体肝移植的实验研究

目的 探讨大鼠原位肝移植过程中,供肝可能耐受心脏停搏热缺血损伤的时间极限,方法 雄性SD大鼠,以供肝获取前供体大鼠经历心脏停搏时间0、15、30、45、60min分为5组（HB组、N-15组、N-30组、N-45组和N-60组）,而后行大鼠原位肝移植,比较各组的术后肝功能、肝脏病理和存活率。结果 HB、N-15、N-30、N-45和N-60的大鼠肝移植术后1周存活率分别为：100%（8/8）、75%（6/8）、62.5%(5/8)、25%（2/8）和0%（0/8）。其中HB、N-15、N-30组和N-45组的大鼠肝移植最长存活时间超过30d。结论 大鼠供肝对于热缺血损伤的时间应越短越好,但耐受30min心脏停搏热缺血损伤时,仍可使1周存活率达62.5%,极限时间为45min。     

热缺血损伤对大鼠移植肝组织能量代谢及存活期的影响

目的：探讨不同热缺血时间下大鼠肝组织能量代谢变化规律,预测供肝耐受热缺血的安全时限。方法：实验动物按供肝热缺血时间分别为0、10、15、20、30、45和60min,随机分为7组。采用反相高效液相色谱法测定单纯热缺血后肝组织能量代谢指标并进行超微结构的观察。然后按各组条件分别作原位肝移植,观察移植后24、48h各组肝组织能量代谢指标的恢复性变化,并统计生存时间。结果：供肝经受热缺血损伤后,肝组织ATP含量和EC水平远逐渐下降,其中前30min下降比较急剧,以后趋向平缓。热缺血30min内肝组织ATP含量和EC水平在肝移植再复流24h后基本得到恢复,术后大鼠仍可以获长期存活。45min组,移植肝在48h后能量代谢的功能也基本恢复,虽不足以影响术后的1周存活率,但对大鼠肝移植术后的3个月存活率影响显著。60min组,肝脏能量代谢储备功能难以恢复,大鼠术后生存天数显著降低。结论：供肝组织三磷酸腺苷（ATP）含量和能荷（EC）水平以及其移植术后恢复的潜能是衡量供肝质量的重要标准。供肝热缺血损伤的时间与肝组织能量代谢功能的恢复及术后动物生存情况密切相关。     

肝移植时供肝耐受无心跳热缺血的安全时限实验研究

目的 探讨肝移植时供肝耐受无心跳热缺血损伤的安全时限。方法 建立广西巴马小型猪原位肝移植动物模型并按移植前供肝经历心脏停搏时间0、30、45、60min分为4组，观测肝移植后各组一周存活率、肝功能、肝脏病理和肝脏能量代谢以及术中肝脏复流后微循环改变。结果上述各组术后一周存活率分别为：100％(5／5)、100％(5／5)、60％(3／5)、20％(1／5)。肝脏能量代谢等指标的改变在供肝无心跳热缺血时间30min前是可逆的，随心跳热缺血时间的延长远渐向不可逆演变。结论 在本实验条件下，巴马小型猪心脏停搏供体肝移植时供肝耐受无心跳热缺血损伤的安全时限约为30min。     

阿霉素预处理对大鼠供肝热缺血再灌注损伤的保护作用

目的探讨阿霉素预处理对无心跳大鼠供肝热缺血再灌注损伤的保护作用。方法根据阿霉素预处理与否及供肝获取前经历的供体心脏停搏时间30min或45min，将实验动物分为4组，即非预处理的30min（N-30）组和45min（N-45）组，阿霉素预处理的30min（tN-30）组和45min（tN-45）组行原位肝移植，观察存活状况，取材行光学显微镜及电子显微镜检查，移植术后1、3、7d采集血样检测肝功能。结果N-30组和N-45组的1周存活率分别为50．0％和16．7％，而tN-30组和tN-45组的1周存活率分别为83．3％和66．7％，预处理组移植肝脏的病理及肝功能明显好于非预处理组。结论阿霉素预处理能够减轻供肝的热缺血再灌注损伤。改善肝功能，减轻病理损害，提高大鼠肝移植的存活率。     

无心跳供肝大鼠肝移植模型的手术操作技巧探讨

目的建立一个稳定的无心跳供肝大鼠原位肝移植模型。方法在Kamada"二袖套法"的基础上进行改良,根据供肝获取前经历无心跳热缺血时间不同分为10min(R10组)、20min(R20组)和30min(R30组)3组,比较各组术后1周大鼠存活率。结果供体手术时间约30min(不含热缺血时间)。供肝冷保存时间均为1h。肝上下腔静脉吻合时间12～22min(平均15min),门静脉和肝下下腔静脉套管分别约需2min和1min。无肝期时间14～24min(平均19min),受体总手术时间50～65min(平均60min)。大鼠术后24h内死亡视为手术失败,共计12例死亡。R10组、R20组和R30组手术成功率分别为95%(19/20)、80%(16/20)和65%(13/20),术后1周生存率分别为95%(18/19)、81%(13/16)和54%(7/13)。结论在Kamada"二袖套法"基础上进行改良的大鼠无心跳供肝肝移植模型能很好地模拟临床无心跳供肝肝移植。大鼠肝脏能耐受30min以内的热缺血时间,移植术后短期存活结果满意,长期存活率尚需进一步研究。     

增加供肝的肝糖原贮备减轻心脏停搏大鼠供肝的热缺血再灌注损伤

目的探讨肝移植术前增加供肝的肝糖原贮备能否减轻心脏停搏大鼠供肝的热缺血再灌注损伤。方法雄性SD大鼠作为肝移植的供、受者被随机分为A、B、C三组。A组供者正常饮水；B组供者术前连续4d饮糖水；C组供者在B组的基础上于供肝获取前3～4h注射500g／L的葡萄糖。A、B、C三组再按供者经历的心脏停搏时间（心脏停搏60min、90min、120min和150min）各分为4个小组，行原位肝移植术并检测移植肝组织中肝糖原和ATP的含量；同时观察受者术后1周存活率以及血清丙二醛（MDA）和超氧化物歧化酶（SOD）的水平。结果B、C两组供肝的肝糖原贮备和ATP含量均明显高于A组（P〈0．01）；B-60min、B-90min、B-120min和C-90min、C-120min、C-150min组受者的1周存活率分别为80％、50％、1（）％和70％、60％、20％，部分受者可长期存活；B、C两组受者MDA水平明显低于A组，SOD水平明显高于A组（P〈0.05）。结论术前增加大鼠供肝的肝糖原贮备能明显减轻供肝的热缺血再灌注损伤，减少了术后原发性移植肝无功能的发生，提高了心脏停搏供肝移植术后的存活率。     

无心跳供体中供肝微循环的动态变化

目的 探讨不同热缺血时间下大鼠无心跳供体肝组织微循环的变化规律，预测供肝耐受热缺血的安全时限。方法 实验动物按供肝热缺血时间分别为0、15、30、45、60min，随机分为5组。然后按各组条件分别作原位肝移植．对肝移植术后各组血清透明质酸(HA)的水平进行动态检测，以及观察肝组织微循环超微结构的动态变化。结果 在热缺血30min以内，移植肝组织复流后能逐渐恢复至正常的微循环结构和功能。热缺血45min，复流后大部分肝血窦腔可逐渐恢复通畅。但部分血窦仍充满较多的膜浆泡和血细胞积滞；热缺血45min以前各组术后3d血清HA可基本恢复。热缺血60min，复流后内皮细胞损伤不但不能恢复，且出现加重、扩大趋势。结论 供肝经受30min以内热缺血损伤，肝组织微循环的变化处在可复性阶段。45min的热缺血时间可能县供肝微循环功能耐受热缺血损伤的极限．热缺血60min以后．呈现不可逆性的微循环障碍．     

供肝热缺血损伤对大鼠肝移植术后胆汁淤积的影响

目的探讨肝移植中供肝热缺血损伤对肝移植术后胆汁淤积的影响。方法实验分为4组：对照组（C）和移植组,移植组根据供肝获取前经历供体心脏停搏时间的不同分为三组：热缺血0min（W0）、热缺血15rain（W15）和热缺血30min（W30）,其后建立大鼠动脉化原位肝移植模型,每组均为30只大鼠,分别于术后3d、7d、14d和30d处死,每个时间点各取6只大鼠,分别测定移植肝组织学、血清ALP和ALT变化。此外,移植组各组随机选取6只大鼠观察长期生存率（〉100d）。结果随着供肝热缺血时间的延长,术后血清ALP逐渐增高,14天达到高峰后逐渐下降。术后第3d、7d、14d、30d血清ALP与供肝热缺血时间具有显著相关性。随着供肝热缺血时间的延长,移植肝损伤加重,并且恢复过程也延长。移植组和对照组术后血清ALT无显著性改变。W0、W15和W30术后长期生存率无明显差别。结论肝移植术后存在胆汁淤积,供肝热缺血时间的延长明显加重胆汁淤积的程度。但是,供肝热缺血30min以内造成的大鼠肝移植术后胆汁淤积并不影响预后。     

Lazaroid对肝移植缺血再灌注损伤的肝保护作用

心脏停搏供体(NHBD)肝移植的临床应用将部分缓解供肝的短缺。我们先期的研究结果表明U-74389G的预处理可以显著提高心脏停搏供体肝移植的存活率，实验中尽管供肝获取经历45或60min的热缺血损伤。U-74389G预处理两组的1周存活率仍然可以达到58．3％和33.3％，显著高于非预处理两组25％和0％的1周存活率，并且U-74389G的预处理还能够改善术后肝功能和移植肝病理状况。在此基础上。我们利用大鼠原位肝移植的模型来探讨Lazaroid U-74389G预处理对供肝热缺血损伤的保护机制。     

外源性三磷酸腺苷-氯化镁预处理对大鼠供肝热缺血损伤的保护作用

目的 观察三磷酸腺苷-氯化镁(ATP-MgCl2)预处理对无心跳大鼠供肝热缺血损伤的保护作用.方法 根据ATP-MgCl2预处理与否及供肝获取前经历的供体心脏停搏时间(即热缺血时间)30min或45min,将实验动物分为4组,即非预处理的30min(N-30min)组和45min(N-45min)组,以及ATP-MgCl2预处理的30min(tN-30min)组和45min(tN-45min)组行原位肝移植,观察存活状况,取材行光学显微镜及电子显微镜检查,移植术后1、3、7d 采集血样检测肝功能.结果 N-30min组和N-45min组的1周存活率分别为50.0%和16.7%,而tN-30min组和tN-45min组的1周存活率分别为83.3%和66.7%,预处理组移植肝脏的病理及肝功能明显好于非预处理组.结论 ATP-MgCl2预处理能够减轻供肝的热缺血损伤,改善肝功能,减轻病理损害,提高大鼠肝移植的存活率.     

不同热缺血时间的无心跳供肝在肝移植中应用的疗效评价

目的:探讨不同热缺血时间的无心跳供肝在临床肝移植中应用的疗效。方法:回顾性分析142例冷保存时间在12h之内的不同热缺血时间的无心跳供肝肝移植患者的临床资料, 根据热缺血时间分为3组：Ⅰ组为5 min之内, 43例; Ⅱ组为5～10 min, 77例; Ⅲ组为10～15 min, 22例。比较3组间肝移植术后谷丙转氨酶（ALT）峰值、原发性移植肝无功能、急性排斥反应、胆道并发症、血管并发症、感染以及移植肝存活和受体存活的差异。结果:3组患者术后均未发生原发性移植肝无功能。Ⅱ组术后ALT峰值及感染发生率显著高于Ⅰ组; 而Ⅲ组术后ALT峰值、胆道并发症发生率、血管并发症发生率及感染发生率均显著升高。随访 8~32个月。Ⅲ组移植肝存活率及受体存活率均降低, 与Ⅰ组和Ⅱ组比较, 差异均有统计学意义。结论:冷保存时间在12 h之内的无心跳供肝能耐受热缺血的安全时限为10 min; 热缺血时间大于10 min的供肝, 移植术后相关并发症发生率显著增加, 移植肝和受体存活率显著降低。     

Analysis of clinical variables of donors and recipients with respect to short-term graft outcome in human liver transplantation

Donor and recipient factors are closely associated with graft survival after orthotopic liver transplantation (OLT). This study was performed to analyze clinical characteristics of recipients and donors, which affect 30-day graft loss after OLT. MATERIALS AND METHODS: One hundred eighty-six livers from heart-beating donors were accepted between May 1997 and June 1998 at the University of Pittsburgh Medical Center. Donor variables that were analyzed included age, sex, cold ischemia time (CIT), warm ischemia time (WIT), imported versus local procurement, cardiopulmonary arrest, serum sodium level, and dopamine dose. The recipient characteristics included native liver disease and UNOS status. Two-sided Fisher exact test and stepwise logistic regression were used for univariate and multivariate analyses. P-values < .05 were considered statistically significant. RESULTS: Twenty-eight grafts (15.1%) were lost within 30 days of OLT. The following factors were found to adversely affect graft survival: donor sodium > 155 mEq/L (P = .002); CIT > 12 hours (P = .002); WIT > 45 minutes (P = .002); and imported liver graft (P = .048). Logistic regression revealed that donor sodium (odds ratio, 3.03; 95% CI, 1.05 to 8.74), CIT (OR 1.20; 95% CI 1.05 to 1.38), WIT (OR 1.06; 95% CI 1.01 to 1.09) were independent predictors of early graft loss. CONCLUSION: Donor hypernatremia as well as warm and cold ischemia times independently affect graft outcomes in the early postoperative period after OLT. Avoidance of long preservation and correction of donor sodium level are recommended to optimize results and survival in OLT.     

Synergistic effect of cold and warm ischemia time on postoperative graft function and outcome in human liver transplantation

Prolonged cold ischemia time (CIT) during graft preservation and warm ischemia time (WIT) during rewarming time have been reported to cause postoperative graft dysfunction after orthotopic liver transplantation (OLT). However, the effects of both CIT and WIT in combination on patient and graft survivals are not yet defined. The aim of this study was to determine whether simultaneously prolonged CIT and WIT were associated with early graft outcomes after clinical OLT. For analysis of liver graft survival within 90 days of OLT and postoperative graft function, 186 consecutive OLT cases were divided into four groups as follows: group A, CIT < 12 hours and WIT < 45 minutes; group B, CIT > 12 hours and WIT < 45 minutes; group C, CIT < 12 hours and WIT > 45 minutes; and group D, CIT > 12 hours and WIT > 45 minutes. The graft loss rates were 5.4% in group A, 9.8% in group B, 11.1% in group C, and 42.9% in group D. The mean highest aspartate aminotransferase (AST) value after OLT in group D (3352.3 +/- 569.4 U/L) was significantly greater than those in groups A (1411.7 +/- 169.2 U/L) and B (1931.3 +/- 362.6 U/L). The simultaneously prolonged cold and warm ischemia times significantly caused hepatic allograft injury and failure, suggesting some cumulative effects of CIT and WIT on postoperative graft function.     

移植肝热缺血损伤后糖原及酶组织化学活性的动态变化

目的：探讨不同热缺血时间下大鼠移植肝组织糖原及酶组织化学活性变化规律，预测供肝耐受热缺血性的安全时限。方法：用组织化学和细胞化学的方法，对大鼠移植肝组织进行动态观察，按热缺血时间随机分为0、15、30、45、60min5组，观察肝移植后的恢复性变化。结果：随热缺血时间的延长，肝组织琥珀酸脱氢酶（SDH）、细胞色素氧化酶（CO）和三磷酸腺苷酸（Mg^2 ,ATPase)活性逐渐降低，糖原减少，热缺血30min以前各组酶活性变化轻微，而45、60min组均出现明显的酶活性降低和高碘酸－无色品红（PAS）反应减低，15、30min组，在复流后24h糖原颗粒逐渐增多，呈明显的恢复，酶活性逐渐恢复至接近正常水平，45、60min组，复流后24hPAS反应和酶活性仍无明显恢复趋势，结论：移植肝热缺血在30min以内，肝组织损伤仍处在可复性阶段，复流后能逐渐恢复至正常的形态和功能，移植肝糖原含量，酶组织化学活性的变化以及术后其恢复性的潜能可作为衡量供肝质量的重要标准。     

大鼠无心跳供体热缺血损伤后供肝组织学与超微结构的动态变化

目的动态观察移植肝热缺血损伤后组织学与超微结构的变化特点，预测无心跳供体（NHBD）中供肝耐受热缺血的安全时限。方法实验动物按供肝热缺血时间分别为0、10、15、20、30、45、60min，随机分为7组。按各组条件分别作原位肝移植，动态观察单纯热缺血期和肝移植术后6h、24h、48h各组移植肝组织学、组织化学和超微结构变化规律。结果NHBD的供肝不仅发生热缺血阶段缺血缺氧造成的损伤，在移植肝复流后，也存在再灌注损伤，且再灌注期肝组织损伤的程度与热缺血时间长短有密切关系。热缺血30min以前，移植肝仅出现组织细胞的变性，未见明显坏死。45min组，肝组织可见小灶状的坏死，在小叶中央区首先发生。60min组，肝细胞坏死的范围扩大，呈片状或弥漫性分布；肝窦内皮细胞明显肿胀呈泡状或气球状，肝血窦阻塞，呈微循环障碍。结论大鼠供肝经受30min以内热缺血损伤，肝组织损伤处在可复性阶段。热缺血60min以后，呈现不可逆性的形态学改变。     

不同热缺血时间犬自体胰移植物功能状态及存活率的实验研究

目的探讨热缺血时间较长犬胰腺移植物功能和组织形态变化状态,研究不同热缺血时间条件下移植物存活率及供胰耐受热缺血的时限。方法根据供胰热缺血不同时间30、60、90、120 min分组,用UW液保存24 h,然后行自体移植,术后连续观察血糖、静脉葡萄糖耐量试验(IVGTT)、胰液淀粉酶、胰液分泌量、血液中胰岛素含量,并进行病理学检测。结果30 min组和60 min组在术后2~3 d即可恢复至正常范围,而在90 min组和120 min组术后1周血糖不能恢复至正常。IVGTT K值在未热缺血组3、0 min组和60 min组在术后1周>1,而在90 min组和120 min组<1。30 min组和60 min组术后胰液淀粉酶、胰液分泌量、血液中胰岛素含量明显高于90 min组和120 min组(P<0.05)。热缺血30、60、90、120 min各组移植物存活率分别为100%、100%、66.7%、0%。结论移植胰腺经过30~60 min热缺血,UW液保存24 h后移植物生存良好。热缺血时间超过90 min,移植物结构和功能难以恢复,存活率明显降低。     

31P NMR assessment of orthotopic rat liver transplant viability. The effect of warm ischemia.

The relationship between NMR visible high energy phosphates and transplant outcome for the case of liver damage by warm ischemia was investigated. In vivo 31P nuclear magnetic resonance (NMR) spectroscopy of rat liver was performed before the induction of warm ischemia in the donor and 20 min after reestablishment of portal blood flow in the recipient. Pretransplant damage was varied by subjecting the livers to 0, 15, 30, or 60 min of warm ischemia prior to harvesting. In the controls (0 min warm ischemia), 4 of 4 rats survived transplantation (one week survival end-point) and the mean NTP recovery was 94 +/- 8%; 3 of 6 rats survived in the 15 min warm ischemia group. Mean NTP recovery was 77 +/- 20% in the 15 min survival subgroup and 32 +/- 20% in the nonsurvival subgroup. Of 6 rats, 1 survived in the 30 min group. NTP recovery was 44% for the 30 min survivor and 37 +/- 5% in the nonsurvival subgroup. Of 4 rats, 1 survived in the 60 min warm ischemia group. NTP recovery was 56% for the 60 min survivor and 28 +/- 7% in the nonsurvival subgroup. Overall, there was a significant difference between the mean NTP recovery of the survival and nonsurvival subgroups (78 +/- 21% versus 31 +/- 18%, P < 0.001). The dividing line between the survival and nonsurvival groups was approximately 50% NTP recovery. Of 9 rats with liver NTP recovery greater than 50%, 8 survived while 10 of 11 rats with less than 50% recovery died. NMR visible NTP recovery 20 min after the reestablishment of portal blood flow was a good indicator of transplant outcome in the case of rat liver damage by warm ischemia.     

The Impact of Anastomosis Time During Kidney Transplantation on Graft Loss: A Eurotransplant Cohort Study

Recent studies raised the concern that warm ischemia during completion of vascular anastomoses in kidney implantation harms the transplant, but its precise impact on outcome and its interaction with other risk factors remain to be established. We investigated the relationship between anastomosis time and graft survival at 5 years after transplantation in 13 964 recipients of deceased donor solitary kidney transplants in the Eurotransplant region. Anastomosis time was independently associated with graft loss after adjusting for other risk factors (adjusted hazard ratio [HR] 1.10 for every 10‐min increase, 95% confidence interval [CI] 1.06–1.14; p < 0.0001), whereas it did not influence recipient survival (HR 1.00, 95% CI 0.97–1.02). Kidneys from donation after circulatory death (DCD) were less tolerant of prolonged anastomosis time than kidneys from donation after brain death (p = 0.02 for interaction). The additive effect of anastomosis time with donor warm ischemia time (WIT) explains this observation because DCD status was no longer associated with graft survival when adjusted for this summed WIT, and there was no interaction between DCD status and summed WIT. Time to create the vascular anastomoses in kidney transplantation is associated with inferior transplant outcome, especially in recipients of DCD kidneys.