Risk factors for infection after liver transplantation

Infection is a common cause of morbidity and mortality after liver transplantation. Risk factors relate to transplantation factors, donor and recipient factors. Transplant factors include ischaemia-reperfusion damage, amount of intra-operative blood transfusion, level and type of immunosuppression, rejection, and complications, prolonged intensive care stay with dialysis or ventilation, type of biliary drainage, repeat operations, re-transplantation, antibiotics, antiviral regimen, and environment. Donor risk factors include infection, prolonged intensive care stay, quality of the donor liver (e.g. steatosis), and viral status. For the recipient the most important are MELD score >30, malnutrition, renal failure, acute liver failure, presence of infection or colonisation, and immune status for viruses like cytomegalovirus. In recent years it has become clear that genetic polymorphisms in innate immunity, especially the lectin pathway of complement activation and in Toll-like receptors importantly contribute to the infection risk after liver transplantation. Therefore, the risk for infections after liver transplantation is a multifactorial problem and all factors need attention to reduce this risk.     

Risk assessment in haematopoietic stem cell transplantation: the liver as a risk factor

Patients with liver dysfunction have an increased risk of developing early and late complications after haematopoietic stem-cell transplantation (HSCT). That's why it is mandatory to evaluate liver status before transplantation in all cases. This evaluation should allow us to decide whether HSCT can be performed or whether we should adopt measures focused on preventing these complications. The evaluation of the liver in an HSCT candidate requires the collection of information by history-taking, physical examination, liver-function tests and, occasionally, imaging tests and liver biopsy. Additionally, as infection by hepatitis B or C viruses represents the most relevant cause of hepatic dysfunction after HSCT, the serological status of the patient should be carefully evaluated. This chapter tries to analyse and systematise the most important aspects in the patient's evaluation. Finally, as some liver dysfunctions in the stem-cell donor can have a negative impact for the donor during the harvest and/or for the recipient during HSCT, the methodology to evaluate the donors will also be analysed.     

Factors associated with prolonged mechanical ventilation following coronary artery bypass surgery

STUDY OBJECTIVES: To identify the typical duration of postoperative mechanical ventilation following coronary artery bypass graft surgery (CABG), and to identify risk factors for prolonged postoperative ventilation. DESIGN: Retrospective study of 4,863 consecutive patients using univariate and multivariate survival analysis to identify independent risk factors. SETTING: Saint Thomas Hospital, Nashville, TN, a 575-bed, academically affiliated, regional referral hospital specializing in cardiovascular diseases. PATIENTS: All patients undergoing CABG in our hospital from January 1, 1996, to December 31, 1997. INTERVENTIONS: None. Measurements and results: Duration of mechanical ventilation and mortality were measured. More than 94% of the patients were extubated in the first 3 days following surgery, 4% more were extubated from postoperative days 4 to 14, and almost 2% were receiving ventilation for > 14 days. Those risk factors that reflect preoperative medical instability, especially cardiac or respiratory insufficiency, were associated with the highest incidence of prolonged postoperative mechanical ventilation and for operative mortality. The Society of Thoracic Surgeons-predicted mortality estimate was the best single independent predictor for prolonged postoperative ventilation. CONCLUSIONS: Typically, patients can be expected to be extubated within 3 days after CABG. Certain preoperative comorbidities, especially preoperative cardiac or respiratory instability, are predictive of prolonged postoperative mechanical ventilation.     

Suppurative mediastinitis after open heart surgery. A case control study of risk factors

Suppurative mediastinitis occurred in 68 of 9,965 patients (0.7 percent) who underwent median sternotomy at Emory University Hospital from 1973 through 1982. Case-control methodology was used to identify preoperative, intraoperative, and postoperative risk factors for the development of poststernotomy mediastinitis. The following 12 individually significant risk factors were identified by univariate analysis: preoperative factors: history of chronic obstructive pulmonary disease (COPD), history of prior sternotomy, pyuria, low ejection fraction, and high left ventricular end-diastolic pressure; intraoperative factors: valvular or aortic aneurysm surgery, prolonged bypass pump time, repeat placement on bypass, duration of surgery; and postoperative factors: surgical reexploration due to postoperative hemorrhage, cardiopulmonary resuscitation in the immediate postoperative period, prolonged time (greater than 48 hours) on mechanical ventilation. By logistic regression analysis, three of these factors were found to be associated independently with increased odds of developing mediastinitis: duration of surgery, history of COPD, and prolonged postoperative mechanical ventilation.     

Successful cardiac transplantation after 38 days of circulatory assistance with a heterotopic artificial heart

The survival of a patient with irreversible cardiac failure on the cardiac transplantation waiting list was assured for 38 days by circulatory assistance with heterotopic Pierce Donachy prosthetic ventricles and followed by successful cardiac transplantation. This method of circulatory assistance is relatively simple to install from the technical point of view and provides a satisfactory haemodynamic result whilst waiting for a compatible donor organ. Several complications, some of them serious, were observed. Some were related to the patient's poor preoperative condition: acute renal failure, disorders of coagulation. These regressed slowly when the patient's haemodynamic status improved. On the other hand, septic problems and local haemorrhage were inherent to this technique. These are the commonest complications reported by other authors. Although the mortality rate during the period of circulatory assistance may appear to be high, this technique remains a valuable method of survival for selected patients and does not affect the chances of success of ulterior cardiac transplantation.     

Liver transplant recipients infected with SARS‐CoV‐2 in the early postoperative period: Lessons from a single center in the epicenter of the pandemic

The impact of coronavirus disease‐19 (COVID‐19) in liver recipients remains largely unknown. Most data derive from small retrospective series of patients transplanted years ago. We aimed to report a single‐center case series of five consecutive patients in the early postoperative period of deceased‐donor liver transplantation who developed nosocomial COVID‐19. Two patients presented important respiratory discomfort and eventually died. One was 69 years old and had severe coronary disease. She rapidly worsened after COVID‐19 diagnosis on 9th postoperative day. The other was 67 years old with non‐alcoholic steatohepatitis, who experienced prolonged postoperative course, complicated with cytomegalovirus infection and kidney failure. He was diagnosed on 36th postoperative day and remained on mechanical ventilation for 20 days, ultimately succumbing of secondary bacterial infection. The third, fourth, and fifth patients were diagnosed on 10th, 11th, and 18th postoperative day, respectively, and presented satisfactory clinical evolution. These last two patients were severely immunosuppressed, since one underwent steroid bolus for acute cellular rejection and another also used anti‐thymocyte globulin for treating steroid‐resistant rejection. Our novel experience highlights that COVID‐19 may negatively impact the postoperative course, especially in elder and obese patients with comorbidities, and draws attention to COVID‐19 nosocomial spread in the early postoperative period.     

The Berlin Heart EXCOR in an 11-year-old boy: a bridge to recovery after myocardial infarction

When a donor heart is not available during the end stage of heart failure, the implantation of a ventricular assist device is the only therapeutic alternative. Many such devices are designed to provide circulatory support to adults, but very few are available for children and infants, especially in the United States. In children, implantation of ventricular assist devices that are designed for adults carries a high risk of complications, because the low stroke volumes that must be used can result in inadequate pump washout and excessive thromboembolic risk. Herein, we report the case of an 11-year-old boy with congenital heart defects who experienced acute myocardial infarction. Prolonged support with the Berlin Heart excor Pediatric ventricular assist device served as a bridge to recovery. The period after device implantation was challenging, because of the need for prolonged inotropic support, continuous mechanical ventilation, the number of reoperations, and the occurrence of sepsis. Nevertheless, after 29 days, the patient's heart recovered, and the device was explanted. He was discharged from the hospital, in good condition, 30 days after removal of the excor device.     

体外循环下心脏瓣膜病换瓣术后ICU延迟脱离呼吸机病例对照研究

目的探讨心脏瓣膜病换瓣术后住ICU延迟脱离呼吸机的危险因素,为制订心脏瓣膜病换瓣术后住ICU延迟脱离呼吸机的防治措施提供依据。方法采用回顾性病例对照研究和非条件logistic多元回归分析方法,收集宜昌市第一人民医院重症医学科2008年1月至2012年1月心脏瓣膜病换瓣术后的71例患者资料,33例住ICU延迟脱离呼吸机患者与脱呼吸机时间无延迟的38例患者进行对照研究。结果心脏瓣膜病换瓣术后住ICU脱呼吸机时间延迟发生率为46．47％。心脏瓣膜病换瓣术后住ICU延迟脱离呼吸机的危险因素有术后低心排、术后。肾功能衰竭、年龄≥50岁、ST—T改变、住ICU〉5d等。心脏瓣膜病换瓣术后住ICU延迟脱离呼吸机的独立危险因素有：术后低心排（OR=5．329,95％CI1．682-16．881）、术后肾功能衰竭（OR=3．163,95％CI1．007-9．931）。结论心脏瓣膜病换瓣术后住ICU延迟脱离呼吸机的独立危险因素是术后低心排和肾功能衰竭。明确心脏瓣膜病换瓣术后住ICU延迟脱离呼吸机的危险因素,以缩短心脏瓣膜病换瓣术后呼吸机机械通气时间。     

Determinants of gastrointestinal complications in cardiac surgery

We designed this study to define determinants of gastrointestinal complications after cardiac surgery. From January 1992 through December 2000, 11,058 patients underwent cardiac surgery on cardiopulmonary bypass at our institution. Data were prospectively collected and univariate and multivariate analyses conducted. A total of 147 gastrointestinal complications occurred in 129 patients (129/11,058; 1.2%) including gastroesophagitis (18, 12.2%), upper gastrointestinal hemorrhage (42, 28.6%), perforated peptic ulcer (7, 4.7%), cholecystitis (10, 6.8%), pancreatitis (13, 8.8%), intestinal ischemia (17, 11.5%), colitis (18, 12.2%), diverticulitis (5, 3.4%), intestinal occlusion (2, 1.1%), lower gastrointestinal hemorrhage (1, 0.7%), and mixed gastrointestinal complications (14, 9.5%). Patients with gastrointestinal complications were significantly older and had significantly higher comorbidity (unstable angina, chronic renal failure, and peripheral vascular disease), morbidity (prolonged mechanical ventilation, intraaortic balloon pumping, bleeding, acute renal failure, stroke, and infection), and mortality rates (22.5% vs 4%, P < 0.0001). They also had longer cardiopulmonary bypass times and higher valvular surgery rates. Multivariate analysis identified 6 independent predictors for gastrointestinal complications: prolonged mechanical ventilation (odds ratio [OR], 5.5), postoperative renal failure (OR, 4.2), sepsis (OR, 3.6), valve surgery (OR, 3.2), preoperative chronic renal failure (OR, 2.7), and sternal infection (OR, 2.4). Factors such as mechanical ventilation, renal failure, and sepsis are the stronger predictors for GI complications, causing splanchnic hypoperfusion, hypomotility, and hypoxia. Furthermore, excessive anticoagulation after valve replacement may lead to GI hemorrhage. Valve surgery, often requiring anticoagulation, increases bleeding. Monitoring mechanical ventilation and hemodynamic parameters, adopting early extubation and mobilization measures, preventing infections, and strictly monitoring renal function and anticoagulation may prevent catastrophic abdominal complications.     

肝移植术后早期急性肺水肿14例临床相关因素分析

目的 探讨肝移植术后早期急性肺水肿的临床相关因素,为临床合理处理提供线索。方法观察我院行肝移植术后急性肺水肿14例患者的术前终末期肝病模型（MELD）评分、手术前后肾功能（尿量、血肌酐）的变化情况;记录移植术中及术后前3d总入量、总出量和液体平衡量。结果肝移植术后急性肺水肿患者（14例）术前MELD评分较非肺水肿组（127例）显著增高（P〈0．01）,且术后死亡率明显上升（P〈0．01）;急性肺水肿患者术前存在肾功能不全,术后血肌酐、尿量延迟恢复;术中、术后液体正平衡显著增加,与非肺水肿组差异均有统计学意义（P〈0．01）。结论肝移植术后早期急性肺水肿与术前高MELD分值、术前肾功能障碍、术后肾功能延迟恢复及术中大量输液、术后限液不足密切相关,术中、术后严格控制出入量平衡,尽快恢复患者肾功能及相关重要脏器支持是防止肝移植早期急性肺水肿的有效措施。     

Retrospective observation of therapeutic effects of adult auxiliary partial living donor liver transplantation on postpartum acute liver failure: A case report

We present a female patient with preterm labor, severe viral hepatitis B of acute phase, hepatic encephalopathy stage Ⅲ and coma.After delivery, the illness was exacerbated and the patient presented with clinical signs of vital organ dysfunctions such as acute respiratory distress syndrome, cerebral edema and hypoxemia that needed mechanical ventilation.Emergency liver transplantation was recommended after multidisciplinary panel consultations.The donor, her mother, consented to donate her right liver.Auxiliary partial orthotopic living donor liver transplantion(APOLDLT) was performed.After operation, the patient was on triple medication of tacrolimus plus mofetil mycophenolate and prednisone for immunosuppression.The combination of antihepatitis B virus(HBV) immunoglobulin and entecavir was initiated for anti-HBV therapy.Both the patient and the donor recovered well without any complications.The patient was followed up regularly.Her liver function, clinical signs and symptoms improved significantly.Until now, the recipient has been living for more than 78 mo free of any complications.The APOLDLT is a life-saving modality for rescuing patients with high-risk acute liver failure following HBV infection without available donor and hence is recommended under standardized antiviral therapy coverage as stated above.     

Apheresis Therapy for Living‐Donor Liver Transplantation

Abstract: Liver transplantation is a fundamental treatment for patients with end‐stage hepatic failure. In order to perform living‐donor liver transplantations under safer conditions, apheresis plays a major role in Japan due to the prevalence of living‐donor liver transplantation wherein later retransplantation is difficult. In our department, the roles of apheresis in liver transplantation are as follows: as bridge therapy to liver transplantation (n = 45); as a supplement to the graft liver until the recovery of hepatic function (n = 77); as treatment for multiple organ failure including posttransplantation renal failure (n = 15); and as a means with which to reduce antibody titers for antibodies such as anti‐A or anti‐B in persons with ABO blood type = incompatible liver transplantation (n = 23). In our department, we have performed 822 liver transplantations at present. Of those cases, 183 were selected wherein apheresis was performed around the time of the operation. In all cases, transplantation with sufficient apheresis was performed before the surgical operation, however, 22 patients (48.9%) died after undergoing surgery. Among the patients who underwent the postoperative apheresis, those in the nonsurvivor group had lower grafted liver weights compared to those of the survivor group. The kidney was the organ that most frequently failed due to postoperative complications. In cases of ABO blood type‐incompatible liver transplantations, patients with high preoperative anti‐A/B IgM antibody titers sustained bile duct complications, patients with high preoperative anti‐IgG antibody titers sustained hepatic necrosis, and patients with high postoperative anti‐A/B IgM and anti‐IgG antibody titers sustained hepatic necrosis most frequently.     

Lungentransplantation

Since the early days of lung transplantation the demand for donor organs has outstripped donor organ availability. Consequently waiting times continue to increase with patients of highest priority often waiting several weeks or even months until a suitable donor organ becomes available resulting in considerable mortality on the waiting list. These issues have led to renewed interest in bridging strategies for patients with end-stage lung disease. The use of endotracheal intubation and mechanical ventilation (MV) has been viewed as a last resort as the majority of intubated patients fail to reach transplantation and those who do tend to have a poor postoperative outcome. New bridging strategies with awake extracorporeal membrane oxygenation (ECMO) seem to be hopeful alternatives in some patients. In the early intensive care unit (ICU) phase primary graft dysfunction, acute rejection, infections and surgical complications are common problems. Later, rejection, infection and sepsis, special airway complications and pulmonary bleeding may be reasons for ICU treatment.     

Acute renal failure during the early postoperative period in adult living-related donor liver transplantation

BACKGROUND/AIMS: Acute renal failure after liver transplantation can occur in some and is an important postoperative complication. Our goal is to clarify the risk factors of acute renal failure after living-related donor liver transplantation (LDLT). METHODOLOGY: From March 1999 to August 2000, ten consecutive patients were investigated the changes of the systemic hemodynamics and the renal function. They were classified into Group A (Creatinine (Cre) was over 2.0 mg/dL) and B (Cre was below 2.0 mg/dL). Retrospective variables were examined with two groups A and B being compared. RESULTS: In both groups, Cardiac Index (CI) was above standard levels. However, the CI levels in Group B were significantly higher than those in Group A (p=0.031). The early postoperative transaminase levels were significantly higher in Group A than in Group B (p=0.049) and graft liver volume/recipient body weight ratio was significantly smaller in Group A than in Group B (p=0.016). CONCLUSIONS: Our study suggests that small-for-size graft or hypovolemia, resulting in the delay of the recovery of graft liver function, may be an important cause of acute renal failure during the early postoperative period in adult LDLT.     

29例原位心脏移植近期疗效报告

目的:总结29例原位心脏移植的近期疗效。方法:2006年10月至2012年12月,对29例终末期心脏病患者行原位心脏移植治疗。受体肺血管阻力为3.6~5.2 wood单位,平均(4.2±1.8)wood单位;应用4℃的HTK液保护供心,供心冷缺血时间为63~360 min,平均(95.5±26.7)min;29例均采用双腔静脉吻合法原位心脏移植手术;术前使用免疫诱导治疗,术后采用环孢素A、霉酚酸酯和泼尼松预防急性排斥反应。结果:术后死亡2例,1例死于术后低心排出量综合征(低心排),1例死于急性右心衰竭。术后早期并发症有急性右心衰竭3例,急性肾衰竭2例,心包大量积液4例。结论:心脏移植近期疗效满意。选择肺血管阻力较低的患者、妥善的供心心肌保护、熟练的手术操作、合理应用免疫抑制剂和正确处理术后肾功能不全是提高心脏移植近期疗效的重要措施。     

Remnant left liver size and recovery of living right liver donors

Purpose

Living donor liver transplantation is a realistic life-saving treatment in regions where deceased donor organs are scarce. The minimum remnant left liver volume (RLLV) requirement for donor right hepatectomy (DRH) varies in different programs of living donor liver transplantation. The present study aimed to determine how significant the RLLV is in the recovery of right liver donors.

Method

A total of 349 consecutive donors who underwent DRH including the middle hepatic vein were divided into nine groups according to the percentage of the RLLV. The peak and recovery of the serum bilirubin level and prothrombin time (PT) in the 1st week after operation and postoperative complications were studied.

Results

The median RLLV was 35.5 (27–49.5) %. Postoperative peak serum bilirubin was highest [74 (25–133) μmol/L] in the group with RLLVs <30 %. This group also had the highest peak PT [18.9 (15.4–24.4) s], although results were similar between groups. Total bilirubin peaked on postoperative days 1–2 in groups with RLLVs ≥35 %. In groups with RLLVs <35 %, total bilirubin peaked on day 3. PT took 1–2 days to peak and nearly approached preoperative values on day 7 in all groups. Complication rates ranged from 0 to 75 %. The rates of complications of Clavien-Dindo grade 3 or above ranged from 0 to 3.8 %. Postoperative peak bilirubin was associated with severe complications (p = 0.031). Age, postoperative peak PT, and RLLV were independent risk factors for prolonged hospital stay.

Conclusion

There was a demonstrable trend of slower recovery of liver function in donors with smaller RLLVs.     

Leberlebendspende

Liver transplantation is the first-line therapy for irreversible acute liver failure, chronic end-stage liver disease, advanced metabolic liver disease, and hepatocellular carcinoma. The ongoing shortage of deceased donor organs and the waiting-list mortality have led to a change in allocation policy with the introduction of the model for end-stage liver disease. Living donation is a further option to reduce the waiting-list mortality. In pediatric recipients, living donation has almost eliminated death while on the waiting list, with excellent short-term and long-term outcomes after transplantation. In contrast, because adult recipients require a greater liver volume, a more extended liver resection is necessary, which increases the donor’s perioperative and postoperative morbidity and mortality risk. The donor’s safety is the greatest concern; therefore, meticulous evaluation and selection of the living donor is the basic prerequisite to reduce the donor risk. The postoperative outcome after living donor liver transplantation is comparable with that for full-size postmortal grafts. However, living donation has several advantages, including the elective setting of the transplantation, an excellent proven graft quality, and a short cold ischemia time. Living donor liver transplantation requires high expertise in liver surgery as well as in split-liver transplantation. Therefore, living donor liver transplantation should be performed only in transplant centers meeting these qualifications.     

Clinical outcome of respiratory failure in patients requiring prolonged (greater than 24 hours) mechanical ventilation

Patients requiring prolonged (greater than 24 hours) mechanical ventilation have various conditions that result in respiratory failure. All patients requiring prolonged mechanical ventilation were subdivided into the following six groups: uncomplicated acute lung injury; respiratory failure complicated by multisystem failure; previous lung disease; trauma; other medical causes; and routine postoperative ventilation. During a one-year period, 327 patients required prolonged mechanical ventilation; acute lung injury and chronic obstructive pulmonary disease were the predominant conditions. Sepsis was both the major predisposing factor for and complication of acute lung injury. Mortality for patients with acute lung injury was 40 percent in the uncomplicated group and 81 percent in patients with acute lung injury complicated by multisystem failure. Acute respiratory failure in association with acute renal failure had a mortality of 89 percent. Number of organ systems involved also correlated with mortality. In patients with chronic obstructive pulmonary disease and pneumonitis or retained secretions, mortality was lower (30 percent), but a significant percentage of these patients (43 percent) became ventilator-dependent. Ventilator dependence did not significantly increase mortality during the course of respiratory failure.     

Surgical risk in patients with cirrhosis

Surgery in the patient with cirrhosis is problematic, as encephalopathy, ascites, sepsis and bleeding are common in the postoperative period. Accurate preoperative assessment and planning, and careful postoperative management have the potential to reduce the frequency and severity of such complications, and reduce the length of hospital stay, but there is little literature evidence to prove this. Operative mortality and other risks correlate with the severity of the liver disease, co-morbidities and the type of surgery. The Child-Turcott-Pugh (CTP) score or model for end-stage liver disease (MELD) score may be used to determine the severity of the liver disease, but must also take into account recent changes in the patient's condition. Surgery that does not involve opening the peritoneum may have slightly better outcomes, as the risk of ascitic leak, sepsis and difficult fluid management are reduced. Mortality rates range from 10% in CTP-A patients to 82% in CTP-C patients. The presence of portal hypertension is an important negative predictor, especially in abdominal surgery, as refractory ascites may occur. Careful monitoring in the postoperative period and early intervention of complications are essential. Hepatic resections in cirrhosis are associated with other considerations such as leaving sufficient liver tissue to prevent liver failure, and are beyond the scope of this review.     

Comprehensive risk assessment for early neurologic complications after liver transplantation

AIM: To determine risk factors for early neurologic complications(NCs) after liver transplantation from perspective of recipient, donor, and surgeon. METHODS: In all, 295 adult recipients were enrolled consecutively between August 2001 and February 2014 from a single medical center in Taiwan. Any NC in the first 30 d post-liver transplantation, and perioperative variables from multiple perspectives were collected and analyzed. The main outcome was a 30-d NC. Generalized additive models were used to detect the non-linear effect of continuous variables on outcome, and to determine cut-off values for categorizing risk. Risk factors were identified using multiple logistic regression analysis. RESULTS: In all, 288 recipients were included, of whom 142(49.3%) experienced at least one NC, with encephalopathy being the most common 106(73%). NCs prolonged hospital stay(35.15 ± 43.80 d vs 20.88 ± 13.58 d, P 0.001). Liver recipients' age 29 or ≥ 60 years, body mass index 21.6 or 27.6 kg/m~2, Child-Pugh class C, history of preoperative hepatoencephalopathy or mental disorders, day 7 tacrolimus level 8.9 ng/m L, and postoperative intraabdominal infection were more likely associated with NCs. Novel risk factors for NCs were donor age 22 or ≥ 40 years, male-to-male gender matching, graftrecipient weight ratio 0.9%-1.9%, and sequence of transplantation between 31 and 174. CONCLUSION: NCs post- liver transplantation occurs because of factors related to recipient, donor, and surgeon. Our results provide a basis of risk stratification for surgeon to minimize neurotoxic factors during transplantation.