Hyponatremia in Cirrhosis: Implications for Liver Transplantation

Abstract

Hyponatremia in cirrhosis is defined as a serum sodium level ≤130 mEq/L and occurs in approximately 22% of patients with cirrhosis. The appearance of hyponatremia in patients with cirrhosis portends a poor prognosis before liver transplantation (LT), independent of the Model for End-Stage Liver Disease (MELD) score. With the development of the MELD-sodium score, the management of hyponatremia has become more relevant than ever before. Overcorrection of hyponatremia before LT or perioperatively can lead to the devastating neurologic condition known as osmotic demyelination syndrome, which is often irreversible and fatal. Therefore, the most important tenet of hyponatremia is to avoid correcting the serum sodium by ≥8 mEq/L in a 24-hour period. Treatment of hyponatremia is highly challenging. The vast majority of patients with cirrhosis have chronic hypervolemic hyponatremia. Fluid restriction increases serum sodium levels, but tolerance and compliance are significant barriers. Diuretic withdrawal is helpful but contributes to worsening fluid overload. There are limited data to support use of intravenous concentrated albumin solutions. The use of the arginine vasopressin antagonists ("vaptans") is contentious; however, they may have a limited role. Risk factors for intraoperative overcorrection of serum sodium include increased utilization of packed red blood cell and fresh frozen plasma transfusions, which are often unavoidable. Intraoperative management is evolving, and more data are needed in regard to the use of sodium-reduced continuous venovenous hemofiltration and the use of trishydroxymethylaminomethane (Tris) to avoid excess sodium rebound. A thorough discussion of the current treatment options before and during LT is given in this review.

Hypervolemic hyponatremia and transplant‐free survival in children with cirrhosis due to biliary atresia

“…In 2016, sodium was incorporated into the MELD score with the objective of prioritizing donor allocation in the United States for the most severe patients . Inclusion of sodium in the PELD model has also been examined in pediatric studies, with conflicting results .…”

“…Hyponatremia in cirrhosis is caused by a generalized circulatory disorder, with characteristics that include vasodilation, portal hypertension, reduced systemic vascular resistance, increased heart output, and hypotension . Most commonly, hyponatremia of the cirrhotic patient is chronic and hypervolemic.…”

“…The accepted criteria for definition of hyponatremia include serum sodium concentration < 130 mEq/L, maintained for a period greater than or equal to 48 hours . Although this is a complication frequently described in the adult cirrhotic population, publications with pediatric populations are scarce . In the two studies cited, a serum sodium concentration of 130 mEq/L was used as cutoff point, but the duration for which the disorder must be maintained was set at a minimum of seven days .…”

“…Electrolytic disturbances are also common and reflect both progression of liver disease and therapeutic intervention variables such as diuretic need . It is not rare for adult patients with ESLD to develop hypervolemic hyponatremia, which is associated with high morbidity and mortality …”

Diagnosis, Evaluation, and Management of Ascites, Spontaneous Bacterial Peritonitis and Hepatorenal Syndrome: 2021 Practice Guidance by the American Association for the Study of Liver Diseases

“…It is reserved for short-term treatment of symptomatic or severe hyponatremia patients or those with imminent LT. When hypertonic saline is used preceding LT, peri-or intraoperative renal replacement therapy (RRT) may be needed to manage hypervolemia (126). The decision to proceed with LT must be individualized based on urgency for transplant, the severity of hyponatremia, and local expertise.…”