2019 Clinical Update in Liver Transplantation

Cardiovascular disease assessment and management in liver transplantation

The prevalence and mortality related to end-stage liver disease (ESLD) continue to rise globally. Liver transplant (LT) recipients continue to be older and have inherently more comorbidities. Among these, cardiac disease is one of the three main causes of morbidity and mortality after LT. Several reasons exist including the high prevalence of associated risk factors, which can also be attributed to the rise in the proportion of patients undergoing LT for metabolic dysfunction-associated steatohepatitis (MASH). Additionally, as people age, the prevalence of now treatable cardiac conditions, including coronary artery disease (CAD), cardiomyopathies, significant valvular heart disease, pulmonary hypertension, and arrhythmias rises, making the need to treat these conditions critical to optimize outcomes. There is an emerging body of literature regarding CAD screening in patients with ESLD, however, there is a paucity of strong evidence to support the guidance regarding the management of cardiac conditions in the pre-LT and perioperative settings. This has resulted in significant variations in assessment strategies and clinical management of cardiac disease in LT candidates between transplant centres, which impacts LT candidacy based on a transplant centre's risk tolerance and comfort level for caring for patients with concomitant cardiac disease. Performing a comprehensive assessment and understanding the potential approaches to the management of ESLD patients with cardiac conditions may increase the acceptance of patients, who appear too complex, but rather require extra evaluation and may be reasonable candidates for LT. The unique physiology of ESLD can profoundly influence preoperative assessment, perioperative management, and outcomes associated with underlying cardiac pathology, and requires a thoughtful multidisciplinary approach. The strategies proposed in this manuscript attempt to review the latest expert experience and opinions and provide guidance to practicing clinicians who assess and treat patients being considered for LT. These topics also highlight the gaps that exist in the comprehensive care of LT patients and the need for future investigations in this field.

Intraoperative management during liver transplantation in the child with mitochondrial depletion syndrome: A case report

INTRODUCTION

Mitochondrial DNA depletion syndrome (MDS) is a kind of autosomal recessive genetic disorder associated with a reduction in mitochondrial DNA (mtDNA) copy number caused by mutations in nuclear genes during nucleotide synthesis, which affects the energy production of tissues and organs. Changes in hemodynamics during liver transplantation may lead to high energy-demanding organs and tissues being vulnerable. This report described the intraoperative management during liver transplantation in a child with MDS. Ultimately, the child was discharged smoothly without any complications.

PRESENTATION OF THE CASE

A five-year-old boy was diagnosed with mitochondrial depletion syndrome preoperatively and scheduled for living donor liver transplantation. The incidence of postreperfusion syndrome (PRS) could not be avoided for 30 min after opening, despite our best efforts to aggressively prevent it before opening. While ensuring hemodynamic stability, we actively prevented and adopted high-energy-demand organ protection strategies to reduce the incidence of postoperative complications. Finally, the child was discharged 28 days after the operation, and no other complications were found.

DISCUSSION

Liver transplantation can be performed for liver failure in this disease to improve the quality of life and prolong the life of patients. As this child has mitochondrial DNA depletion syndrome, the disruption of cellular energy generation caused by mitochondrial malfunction puts high-energy-demanding organs and tissues at risk during surgery. It motivates us to pay closer attention to the prevention and treatment of PRS in anesthetic management to minimize damage to the child's organs and tissues with high energy demands.

CONCLUSIONS

This report describes the intraoperative management during liver transplantation in a child with mitochondrial depletion syndrome. To increase the safety of perioperative anesthesia and reduce mortality in patients with mitochondrial disease, for such patients, maintaining an acid-base balance and a stable internal environment is essential. We should also pay attention to protecting body temperature, using vasoactive drugs beforehand to lessen the incidence of PRS, and protecting high-energy-demanding organs afterward.

The perioperative period of liver transplantation from unconventional extended criteria donors: data from two high-volume centres

BACKGROUND

As literature largely focuses on long-term outcomes, this study aimed at elucidating the perioperative outcomes of liver transplant patients receiving a graft from two groups of unconventional expanded criteria donors: brain dead aged > 80 years and cardiac dead.

METHODS

Data of 247 cirrhotic patients transplanted at two high volume liver transplant centers were analysed. Confounders were balanced using a stabilized inverse probability therapy weighting and a propensity score for each patient on the original population was generated. The score was created using a multivariate logistic regression model considering a Comprehensive Complication Index ≥ 42 (no versus yes) as the dependent variable and 11 possible clinically relevant confounders as covariate.

RESULTS

Forty-four patients received the graft from a cardiac-dead donor and 203 from a brain-dead donor aged > 80 years. Intraoperatively, cardiac-dead donors liver transplant cases required more fresh frozen plasma units (P < 0.0001) with similar reduced need of fibrinogen to old brain-dead donors cases. The incidence of reperfusion syndrome was similar (P = 0.80). In the Intensive Care Unit, both the groups presented a comparable low need for blood transfusions, renal replacement therapy and inotropes. Cardiac-dead donors liver transplantations required more time to tracheal extubation (P < 0.0001) and scored higher Comprehensive Complication Index (P < 0.0001) however the incidence of a severe complication status (Comprehensive Complication Index  ≥ 42) was similar (P = 0.52). ICU stay (P = 0.97), total hospital stay (P = 0.57), in hospital (P = 1.00) and 6 months (P = 1.00) death were similar.

CONCLUSION

Selected octogenarian and cardiac-dead donors can be used safely for liver transplantation.

New onset atrial fibrillation during orthotopic liver transplantation induced by iced saline injection for transpulmonary thermodilution: a case report

Transpulmonary thermodilution is often used to measure extravascular lung water during liver transplantation. Here, the case of new onset atrial fibrillation during orthotopic liver transplantation, which may have been induced by iced saline injection for transpulmonary thermodilution measurement, is described. A 52-year-old male patient underwent orthotopic liver transplantation due to alcoholic cirrhosis combined with portal hypertension. During dissection of the recipient liver, transpulmonary thermodilution was performed. At 3 minutes following iced saline injected, atrial fibrillation occurred, the ventricular rate increased to more than 120 beats per min, and blood pressure dropped to 75/50 mmHg. Massive haemorrhage, inferior vena cava clamping, electrolyte disorder, acid-base balance disorder, and hypothermia were all ruled out, and iced saline injection was suspended. Hemodynamic stability was maintained with phenylephrine and lanatocide C (cedilanid), and chemical cardioversion was performed using amiodarone. During the reperfusion phase, transient hemodynamic instability was managed by norepinephrine. The neohepatic phase was uneventful. Atrial fibrillation lasted for 5 days and reversed to sinus rhythm automatically. The patient was hemodynamically stable during this period, and recovery was smooth with no thromboembolic events. In conclusion, atrial fibrillation may be induced by iced saline injection for transpulmonary thermodilution measurement during orthotopic liver transplantation.

Modelling kidney outcomes based on MELD eras - impact of MELD score in renal endpoints after liver transplantation

Background

Acute kidney injury is a common complication in solid organ transplants, notably liver transplantation. The MELD is a score validated to predict mortality of cirrhotic patients, which is also used for organ allocation, however the influence of this allocation criteria on AKI incidence and mortality after liver transplantation is still uncertain.

Methods

This is a retrospective single center study of a cohort of patients submitted to liver transplant in a tertiary Brazilian hospital: Jan/2002 to Dec/2013, divided in two groups, before and after MELD implementation (pre-MELD and post MELD). We evaluate the differences in AKI based on KDIGO stages and mortality rates between the two groups.

Results

Eight hundred seventy-four patients were included, 408 in pre-MELD and 466 in the post MELD era. The proportion of patients that developed AKI was lower in the post MELD era (p 0.04), although renal replacement therapy requirement was more frequent in this group (p < 0.01). Overall mortality rate at 28, 90 and 365 days was respectively 7%, 11% and 15%. The 1-year mortality rate was lower in the post MELD era (20% vs. 11%, p < 0.01). AKI incidence was 50% lower in the post MELD era even when adjusted for clinically relevant covariates (p < 0.01).

Conclusion

Liver transplants performed in the post MELD era had a lower incidence of AKI, although there were more cases requiring dialysis. 1-year mortality was lower in the post MELD era, suggesting that patient care was improved during this period.

Human Amnion-Derived Mesenchymal Stromal/Stem Cells Pre-Conditioning Inhibits Inflammation and Apoptosis of Immune and Parenchymal Cells in an In Vitro Model of Liver Ischemia/Reperfusion

Ischemia/reperfusion injury (IRI) represents one of the leading causes of primary non-function acute liver transplantation failure. IRI, generated by an interruption of organ blood flow and the subsequent restoration upon transplant, i.e., reperfusion, generates the activation of an inflammatory cascade from the resident Kupffer cells, leading first to neutrophils recruitment and second to apoptosis of the parenchyma. Recently, human mesenchymal stromal/stem cells (hMSCs) and derivatives have been implemented for reducing the damage induced by IRI. Interestingly, sparse data in the literature have described the use of human amnion-derived MSCs (hAMSCs) and, more importantly, no evidence regarding hMSCs priming on liver IRI have been described yet. Thus, our study focused on the definition of an in vitro model of liver IRI to test the effect of primed hAMSCs to reduce IRI damage on immune and hepatic cells. We found that the IFNγ pre-treatment and 3D culture of hAMSCs strongly reduced inflammation induced by M1-differentiated macrophages. Furthermore, primed hAMSCs significantly inhibited parenchymal apoptosis at early timepoints of reperfusion by blocking the activation of caspase 3/7. All together, these data demonstrate that hAMSCs priming significantly overcomes IRI effects in vitro by engaging the possibility of defining the molecular pathways involved in this process.