Patient selection for liver transplantation

Intraoperative systemic biomarkers predict post-liver transplantation acute kidney injury

OBJECTIVE

Liver transplant (LT) is a definitive therapeutic option for patients with chronic liver disease. However, acute kidney injury after LT (post-LT AKI) is a frequent complication that may lead to graft dysfunction and decrease life expectancy. Delay in AKI detection by traditional biomarkers boosted research with new biomarkers for post-LT AKI as neutrophil gelatinase-associated lipocalin (NGAL) and syndecan-1. We aim to evaluate associations of intraoperative systemic NGAL and syndecan-1 levels with post-LT AKI.

METHODS

This is a prospective study conducted in 46 patients selected for LT. Patients were evaluated preoperatively and blood samples were collected intraoperatively: T1 (after induction of anesthesia), T2 (anhepatic phase) and T3 (2 h after reperfusion of the graft).

RESULTS

The mean age was 54 ± 12 years and 60% were male. Post-LT AKI was observed in 24 (52%) patients of which 12% needed dialysis. Serum NGAL and syndecan-1 increased along surgical phases. Mostly, increment values of serum NGAL of T2 to T3 and syndecan-1 at T3 were importantly associated with post-LT AKI. Into a multivariate model with model for end-stage liver disease score, age, gender, warm ischemia, cold ischemia and surgery time, syndecan-1 levels at T3 remains capable to predict post-LT AKI. Serum NGAL had significance only with increment values calculated by the ratio of 'T3/T2'. Finally, serum syndecan-1 at T3 had a better diagnostic performance in receiver operating characteristic curve analysis.

CONCLUSION

Serum syndecan-1 levels in 2 h after reperfusion were most useful in early post-LT AKI diagnosis and may be used to construct new risk groups in this context.

Keeping Patients with End-Stage Liver Disease Alive While Awaiting Transplant: Management of Complications of Portal Hypertension

Complications of portal hypertension such as gastroesophageal variceal hemorrhage, ascites, and spontaneous bacterial peritonitis, as well as pulmonary complications, are often responsible for diminished quality of life, excess morbidity and mortality, increased health care resource use and expenditure, and dropout from the liver transplant (LT) waiting list. Therefore, the care of LT candidates on the waiting list must be centered on anticipation and prompt intervention for these complications.

Expanding Indications for Liver Transplant: Tumor and Patient Factors

During the past few decades, liver transplant has developed from a high-mortality procedure to an almost routine procedure with good survival outcomes. The development of living donor liver transplant has increased the availability of liver grafts, and the scope of indications for liver transplant has been expanding ever since. The aim of this review is to provide an overview of such an expansion of scope. Various criteria have been proposed to expand the eligibility of patients with hepatocellular carcinoma exceeding the Milan criteria for liver transplant. Furthermore, liver transplant is increasingly performed as a treatment modality for cholangiocarcinoma, neuroendocrine liver metastasis and colorectal liver metastasis. The number of elderly patients receiving liver transplant is on the rise. Combined organ transplantation has also been adopted to treat patients with multiple organ failure. Going forward, further development of preoperative noninvasive predictors in tumor, patient and even donor factors is needed to identify patients at risk of poor outcomes and hence optimize patient management.

Systemic hemodynamics in advanced cirrhosis: Concerns during perioperative period of liver transplantation

Advanced liver cirrhosis is usually accompanied by portal hypertension. Long-term portal hypertension results in various vascular alterations. The systemic hemodynamic state in patients with cirrhosis is termed a hyperdynamic state. This peculiar hemodynamic state is characterized by an expanded blood volume, high cardiac output, and low total peripheral resistance. Vascular alterations do not disappear even long after liver transplantation (LT), and recipients with cirrhosis exhibit a persistent systemic hyperdynamic state even after LT. Stability of optimal systemic hemodynamics is indispensable for adequate portal venous flow (PVF) and successful LT, and reliable parameters for optimal systemic hemodynamics and adequate PVF are required. Even a subtle disorder in systemic hemodynamics is precisely indicated by the balance between cardiac output and blood volume. The indocyanine green (ICG) kinetics reflect the patient’s functional hepatocytes and effective PVF, and PVF is a major determinant of the ICG elimination constant (kICG) in the well-preserved allograft. The kICG value is useful to set the optimal PVF during living-donor LT and to evaluate adequate PVF after LT. Perioperative management has a large influence on the postoperative course and outcome; therefore, key points and unexpected pitfalls for intensive management are herein summarized. Transplant physicians should fully understand the peculiar systemic hemodynamic behavior in LT recipients with cirrhosis and recognize the critical importance of PVF after LT.