Risk Factors of Mortality After Liver Transplantation in Uruguay

Introduction

Identification of predictive factors of mortality in a liver transplant (LT) program optimizes patient selection and allocation of organs.

1例儿童供肝成人移植术后黄疸的原因分析及护理

总结1例脑死亡儿童供肝成人移植术后黄疸的原因及其护理体会.提出儿童供肝体积较小,对免疫抑制剂等药物的代谢能力较成人肝脏差,黄疸原因主要考虑为FK506药物中毒.儿童供肝成人移植术后应根据患者的临床表现,结合供肝的具体情况适当调整免疫抑制剂的使用;护理人员应严格掌握各免疫抑制剂的药理作用、用法、用量、毒副作用,注意对肝功能、药物不良反应的病情观察及护理.     

Risk Factors for Inadvertent Hypothermia During Adult Living-Donor Liver Transplantation

Background

Hypothermia (core temperature <35°C) causes multiple physiologic disturbances, including coagulopathy and cardiac dysfunction. Patients undergoing liver transplantation are at risk of inadvertent hypothermia and might be more vulnerable to its adverse effects. We sought to identify the factors contributing to hypothermia during living-donor liver transplantation (LDLT), which have not yet been studied in depth.

Methods

Medical records of 134 recipients who underwent adult-to-adult LDLT were reviewed. Core temperature at the following time points were taken: anesthetic induction, skin incision, start and end of the anhepatic phase, and hourly after hepatic reperfusion.

Results

Of 134 recipients, 29 (21.6%) developed hypothermia during surgery. Four independent risk factors for hypothermia were identified: small body weight–to–body surface area ratio, acute hepatic failure, high Model for End-Stage Liver Disease (MELD) score, and low graft-to-recipient weight ratio. The amount of core temperature drop was positively correlated with the number of involved risk factors. Each risk factor had a respective contribution according to the operative phases: body weight–to–body surface area ratio and the MELD score for the preanhepatic phase, acute deterioration of hepatic failure for the anhepatic phase, and graft-to-recipient weight ratio was for the postreperfusion phase.

Conclusions

Hypothermia was independently associated with the recipient's morphometric characteristics, emergency of end-stage liver disease, MELD score, and graft volume. These factors showed a cumulative effect, and the role of each factor was different according to the operative phase. These results should aid in the development of an optimal thermal strategy during LDLT.     

Anesthetic Risk Factors Associated With Early Mortality in Pediatric Liver Transplantation

Introduction

Early mortality in pediatric patients after liver transplantation (30 days) may be due to surgical and anesthetic perioperative factors.

Objective

To identify anesthetic risk factors associated with early mortality in pediatric patients who undergo liver transplantation (OLT).

Materials and Methods

This retrospective study of all patients who underwent a deceased or living donor liver transplantation evaluated demographic variables of age, weight, gender, degree of malnutrition, and etiology, as well as qualitative variables of anesthesia time, bleeding, massive transfusion, acid-base balance, electrolyte and metabolic disorders, as well as graft prereperfusion postreperfusion characteristics. Chi-square tests with corresponding odds ratio (OR) and 95% confidence intervals as well as Interactions were tested among significant variables using multivariate logistic regression models. P ≤.05 was considered significant.

Results

We performed 64 OLT among whom early death occurred in 20.3% (n = 13). There were deaths associated with malnutrition (84.6% vs 43.6%) in the control group (P < .01); massive bleeding, 76.9% (n = 10) versus 25.8% in the control group (P < .05) including transfusions in 84.6% (n = 11) versus 43.6% in the control group (P < .03); preperfusion metabolic acidosis in 84.6% (n = 11) versus 72.5% (n = 37; P < .05); posttransplant hyperglycemia in 69.2% (n = 9) versus 23.5% (n = 12; P < .01); and postreperfusion hyperlactatemia in 92.3% (n = 12) versus 68.6% (n = 35; P < .045).

Conclusion

Prereperfusion metabolic acidosis, postreperfusion hyperlactatemia, and hyperglycemia were significantly more prevalent among patients who died early. However, these factors were exacerbated by malnutrition, bleeding, and massive transfusions. Postreperfusion hypokalemia and hypernatremia showed high but not significant frequencies in both groups.     

受体门静脉分支"剖并"成形法在小儿肝移植中的应用

目的　探讨小儿肝脏移植时受体门静脉成形方法 ,改善门静脉重建效果。　方法　沿受体门静脉左右干支头侧纵行劈开血管壁 ,使门静脉左右干支血管壁展开呈矩形的血管壁片 ,从门静脉主干分叉处前壁中点向上连续外翻缝合门静脉前壁 ,同法缝合门静脉后壁 ,受体门静脉被成形为略呈喇叭口状残端。　结果　 12例小儿肝移植时经过受体门静脉“剖并”成形后 ,受体门静脉长度延长 (1.8± 0 .6 )cm ,口径比原来门静脉主干口径扩大 4 6 %± 17%。供、受体门静脉口径接近匹配 ,吻合口无张力 ,吻合效果满意。手术后近期彩色多普勒检测门静脉血流通畅 ,远期随访无狭窄、扭曲、血栓形成等并发症。　结论　受体门静脉分支“剖并”成形法可以明显地改善小儿肝移植时门静脉重建效果。     

Predictive Factors of Liver Dysfunction After Right Hemihepatectomy for Adult Living Donor Liver Transplantation

Background

Living liver donors represent a special group of patients. They are healthy individuals who are exposed to a major surgery, in which the dominant liver proportion is extracted as a graft. Of all potential donor-related morbidities, posthepatectomy liver dysfunction (PHLD) is the most significant as it may be directly related to donor mortality. We aimed to review our data of adult living donor liver transplantation (LDLT) utilizing the right hemiliver grafts to determine the incidence and potential predictors for the development of PHLD, defined according to the International Study Group of Liver Surgery.

Adult Living Donor Liver Transplantation

Adult living donor liver transplantation (LDLT) begun in response to deceased donor organ shortage and waiting list mortality, grew rapidly after its first general application in the United States in 1998. There are significant risks to the living donor, including the risk of death and substantial morbidity, and two highly publicized donor deaths have led to decreased LDLT since 2001. Significant improvements in outcomes have been seen over recent years that have not been reported in single center studies; however, LDLT still comprises less than 5% of adult liver transplants, significantly less than in kidney transplantation where living donors now comprise the majority. The ethics, optimal utility and application of LDLT remain to be defined. In addition, studies to date have focused on post-transplant outcomes and not included the potential impact of LDLT on waiting time mortality. Future analyses should include appropriate control or comparison groups that capture the effect of LDLT on overall mortality from the time of listing. Further growth of LDLT will depend on defining the optimal recipient and donor characteristics for this procedure as well as broader acceptance and experience in the public and in transplant centers.     

成人肝移植术后呼吸系统管理和功能监测

目的：探索肝移植术后呼吸功能监测维持的规律,提高肝移植术后管理质量,方法：分析5例原位肝移植病人在术后ICU期经历的呼吸系统并发症和常见问题,结果：4例肝移植术后出现各种呼吸道并发症9例次,包括肝肺综合征、胸腔积液、肺不张、肺充血、肺间质水肿、肺感染及呼吸道出血,结论：呼吸机的使用和呼吸的监控是肝移植术后管理的重要环节。了解肝移植术后呼吸系统病理生理学改变的规律和特殊性,对于患安全渡过ICU阶段至关重要。     

Factors Associated With Persistent Thrombocytopenia after Liver Transplantation

Background

Thrombocytopenia typically resolves with resolution of portal hypertension after liver transplantation (LT) but persists in some patients. Identifying risk factors associated with persistent post- LT thrombocytopenia may provide important information about its pathogenesis.

Methods

Cirrhotic adults with platelet levels of <150,000 μ/L at the time of LT and followed at least 1 year were studied. A retrospective analysis of lab values, radiologic spleen index (SI), and donor data using nonparametric methods was performed to characterize patients having persistent thrombocytopenia, defined as persistently low platelet levels at 3 and 12 months after LT.

Results

One hundred patients were studied: mean age 55 y (range 23-75 y); platelet count at LT 62,000/μL (range 14,000- 148,000/μL; mean total bilirubin 2.6 mg/dL; mean Mayo end-stage liver disease score 29; SI 1,476 (range 347-4,843 mL; normal 120-480 mL). Platelet count at 3 and 12 months after LT correlated with SI (r = −0.41 and −0.54; P < .001). Fifty-seven patients had persistent thrombocytopenia. Compared with patients whose platelet levels normalized by month 3 or 12, they had higher SI and lower platelet count before LT (P < .001). The SI and platelet levels at the time of LT were independent predictive factors for platelet levels at 3 and 12 months after LT (P < .001).

Conclusions

High SI and low platelet count at the time of LT are associated with persistent thrombocytopenia after LT. They are also independent predictive factors of platelet levels at 3 and 12 months after LT. This suggests that patients may have persistent thrombocytopenia after LT owing to persistence of some degree of hypersplenism and incomplete resolution of splenomegaly.     

肝移植术后急性肺损伤的观察与分析

目的 分析肝脏移植患者术后并发急性肺损伤(AU)的危险因素，并探讨其防治措施。方法 采用回顾性调查的方法，对4例肝脏移植患者的相关资料进行分析。结果 门肺高压症、呼吸机长期使用、严重感染、全身炎性反应综合征、高凝状态、液体超载、肾功能障碍等．是肝移植术后并发急性肺损伤及急性呼吸窘迫综合征(ARDS)的危险因素。结论 肝移植术后易发生ALI，预防并减少相关危险因素的影响．对减少术后ALI及ARDS有重要意义。     

Liver Transplantation With Incidental Gallbladder Carcinoma in the Recipient Hepatectomy

Gallbladder carcinoma(GBCA) is the most common malignancy of the biliary tract¹ and is often found seredipitiously after cholecystectomy. We report the first two cases of incidental GBCA in the native gallbladder of two liver transplant recipients. Both patients are 2.5 years following uneventful orthotopiic liver transplantation(OLTx) with no evidence of recurrent disease. Pathology of both recipients was early and favorable. Neither patient received any further therapy. Given the incidence of GBCA and the evolution of OLTx we would anticipate this finding to be more prevalent.     

Donor Outcomes After Liver Donation in Adult to Adult Living Donor Liver Transplantation

Objectives

This study aims to investigate postdonation outcomes of adult living donor liver transplantation donors and remnant liver regeneration in different graft types.

Side-to-Side Cavocavostomy in Adult Piggyback Liver Transplantation

Objective

Our objective was to perform a retrospective study that described the anastomosis technique as well as the complications of side-to-side cavo-caval reconstruction.

Patients and Methods

From June 1998 to April 2011, we performed 284 liver transplantations including 10 adults with live donor organs. In all cases but 2 (272), cavo-caval reconstruction was performed using side-to-side cavo-caval (STSCC) anastomosis. In 19 cases (6.9%), we also carried out an end-to-side temporary porto-caval shunt (TPCS). In 17 cases (6.2%) the technique was performed for retransplantation.

Results

STSCC anastomosis was technically feasible in all but 2 cases, regardless of the recipient's vena cava, anatomic factors, or graft size. Mean operative time for the STSCC was 13 minutes (range, 6-25). Routine Doppler ultrasonography was performed intraoperatively at the end of the surgery. There was no case of cava stump thrombosis. Complications associated with this technique were limited to 2 patients. One complication was torsion due to donor graft/recipient mismatch, which was successfully treated surgically by falciform ligament fixation. The second complication was only evident by sinusoidal congestion and was managed nonoperatively. Seventeen cases were uneventful for retransplant recipients.

Conclusions

STSCC during piggyback liver transplantation is safe and can be performed in the retransplantation setting, with a low incidence of venous outflow obstruction that can be associated with the traditional piggyback technique. Our data suggest that donor graft to recipient mismatch is not an absolute contraindication when proper body size match is considered. A wide anastomosis with typical recipient hepatic vein inclusion is warranted with routine postanastomotic Doppler ultrasonography.     

Pulmonary Hypertension as a Predictor of Postoperative Complications and Mortality After Liver Transplantation

Most transplant centers consider severe pulmonary hypertension (PHT) to be an absolute contraindication for orthotopic liver transplantation (OLT). We retrospectively examined the outcome of 24 patients with PHT (group 1) who underwent OLT compared with 24 matched patients (group 2) without PHT, who also underwent OLT. Based on right cardiac catheterization measurements made after the induction of anesthesia for OLT, PHT was defined as mild or moderate-to-severe if the mean pulmonary arterial pressure exceeded 25 or 35 mm Hg, respectively. The incidence of PHT was 9.8% (24/244); 21/24 PHT patients showed mild and 3/24 moderate PHT. Kaplan-Meier survival analysis did not show a significant difference between the two groups. The incidence of pulmonary infections was significantly greater in group 1 (P < .05). The duration of ventilation and intensive care unit stay was similar in the two groups. Echocardiography detected only the three moderate cases of PHT and not the twenty-one cases of mild PHT. Our analysis suggested that mild PHT was common and did not affect patient outcomes after OLT; moderate or severe PHT was uncommon. The two patients with moderate PHT survived OLT and did not succum to PHT during long-term follow-up.     

MELD and Other Factors Associated with Survival after Liver Transplantation

Allocation of cadaveric livers for transplantation in the United States is now based on the severity of illness as determined by the model for end-stage liver disease (MELD) score, a function of bilirubin, creatinine and international normalized ratio (INR). The aim of our study was to determine the association of various pre-transplant risk factors, including the MELD score, on patient survival after orthotopic liver transplantation (OLT). The medical records of 499 consecutive patients (233 female, 266 males, mean age 50.9 +/- 10.6 years) undergoing cadaveric OLT at our institution between June 1990 and February 1998 were reviewed. In the 407 patients alive at the latest contact, follow-up was 4.7 years, with a minimum of 20 months (maximum of 9.4 years). Variables considered for analysis included MELD score, age, pre-transplant renal dysfunction requiring dialysis, Child-Pugh classification, underlying liver disease, diabetes mellitus, and heart disease (ischemic/valvular/other). There were 92 deaths during follow-up. In univariate analysis, the MELD score, renal failure requiring hemodialysis pre-OLT, age > 42 years, and underlying etiology of liver disease were significantly associated with death during long-term follow-up. In multivariate models, age, underlying etiology of liver disease and renal failure requiring hemodialysis were independent predictors of death after OLT.     

Postoperative Donor Liver Damage Can Predict Recipient Short-Term Survival in Living Donor Liver Transplantation

BackgroundIn living donor liver transplantation, surgical damage is a risk for graft dysfunction. We hypothesized that postoperative donor laboratory data reflect both donor liver damage and graft damage. Therefore, we evaluated how donor surgical factors affected recipient graft function and prognosis.Patients and MethodsFrom March 2002 to December 2020, 130 consecutive recipients and donors who underwent adult-to-adult living donor liver transplantation were analyzed. Donor perioperative surgical factors were evaluated to assess risk factors for recipient 90-day mortality by univariate analysis.ResultsDonor postoperative maximum levels of aspartate aminotransferase (AST; P = .016), alanine transaminase (P = .048), and prothrombin time-international normalized ratio (P = .034) were risk factors. Receiver operating characteristic analysis identified 214 U/L as the most appropriate cutoff value of donor postoperative AST.After excluding 22 pairs of patients without donor data, the 108 pairs were divided into 2 groups based on donor maximum AST (D-mAST) level: the low D-mAST group (D-mAST < 241 U/L, n = 39) and the high D-mAST group (D-mAST ≥ 241 U/L, n = 69). Donor age was significantly higher in recipients in the high D-mAST group than in the low D-mAST group (P = .033). Postoperative recipient maximum AST and alanine transaminase levels and 90-day mortality were significantly higher in the high D-mAST group than in the low D-mAST group (P = .001, P = .006, and P = .009, respectively). There were no significant differences in long-term survival, although 5-year survival was slightly lower in the high D-mAST group.ConclusionsSurgical liver damage to grafts, as assessed by postoperative donor AST levels, affected recipient short-term survival.     

肝移植术后妊娠

目的探讨肝移植术后妊娠的指征，母体和胎儿／新生儿存在的风险及其处理措施。方法复习相关文献并进行综述。结果肝移植术后多数育龄妇女可以恢复正常月经周期。高血压、肾功能损害、先兆子痫、继发于免疫抑制的细菌和病毒感染以及剖宫产几率增加是母体的主要风险。胎儿／新生儿的风险主要是流产、早产、胎膜早破、肾上腺皮质功能不足、胎儿畸形、免疫缺陷和巨细胞病毒、乙肝病毒及细菌感染。结论在多数患者，肝移植术后妊娠可以获得良好效果，但在妊娠前应进行严格的评估，在妊娠期应多科联合进行严密的监测。当前应制定一个基于现有研究结果的肝移植术后妊娠指南。     

Donor and Recipient Factors Predicting Time to Graft Failure Following Orthotopic Liver Transplantation: A Transplant Risk Index

Introduction

Much of the success of a transplant depends on appropriate matching of donor to recipient.

Methods

We validated the Donor Risk Index formula (DRI) using Mount Sinai Medical Center's 10-year cohort of over 1000 transplants.

Results

The DRI was significantly associated to graft failure with a relative risk (RR) of 1.32. Our cohort had an average DRI of 2.6 with survival of 83% at 3 months, 79% at 1 year, and 70% at 3 years. The low rate of graft failure at a high DRI implies that there are other factors important in transplant pairing that are not considered in the DRI model. To determine these variables and quantify their importance, we constructed a Transplant Risk Index by identifying recipient and donor variables not captured in United Network for Organ Sharing (UNOS) that significantly correlated to graft failure. The most significant independent predictors of time to graft failure were donor age, weight, and peak serum sodium; ischemia time; and recipient creatinine, international normalized ratio, and hepatitis C infection. The coefficients for each of these factors were compiled into a Transplant Risk Index formula. A cutoff of 5 resulted in a graft survival rate of 86% at 3 months, 76% at 1 year, and 62% at 3 years using Kaplan-Meier analysis. The predictive ability of the Transplant Risk Index was greater than the DRI or DMELD (the product of donor age and preoperative MELD) as assessed by the area under the receiver operating curve and the positive and negative predictive values.

Conclusion

The Transplant Risk Index captures recipient factors and donor factors not captured in UNOS. Including these factors may improve the ability to predict good donor–recipient pairing.