Hyponatremia As A Predictor of Death in End Stage Liver Disease Patients

Background: Hyponatremia, defined as serum sodium concentration less than 135 mEq/L. The prevalence of hyponatremia in the ICU can be as high as 30% to 40%. Regarding end stage liver disease (ESLD) patients; hyponatremia is a common problem and is associated with increased duration of hospital stay and increased morbidity and mortality. Aim of the work is to detect the prognostic value of hyponatremia in end stage liver disease (ESLD) patients and its impact on the outcome of these patient. Patients and methods: 118 patients were grouped on the basis of serum sodium concentration at time of presentation. Results: Mortality was found to be insignificantly higher in hyponatremic patients with serum sodium level 130 mEq/L (83.7%). The study also showed significant decrease in serum sodium level at the end of the study compared to time of admission (p-value 0.0001). Conclusion: Hyponatremia is common among ESLD patients, and it is positively associated with long duration till death of patients, it is significantly decreased from start to end of study meaning that progressive hyponatremia is a strong predictor of death in ESLD patients Introduction: Hyponatremia, defined as serum sodium concentration less than 135 mEq/L (Schrier, 2000), represents relative excess of body water relative to body sodium content, because sodium is the major extracellular solute (approximately 90 percent of these solutes), changes in total body sodium result in similar changes in extracellular volume (Vander et al., 2001). The prevalence of hyponatremia in the ICU can be as high as 30% to 40% (Lohani et al., 2011). As regard end stage liver disease patients; hyponatremia is a common problem and is associated with increased duration of hospital stay and increased morbidity and mortality (Friedman et al., 2012). The pathogenesis of hyponatremia in patients with advanced cirrhosis is directly related to the hemodynamic changes and secondary neurohumoral adaptations that occur, resulting in an impaired ability to excrete ingested water. The severity of the hyponatremia is related to the severity of the cirrhosis (Gines and Guevara, 2008). The normal concentration range of sodium in the plasma is 135 145 mill equivalents per liter, making sodium the ion with the most significant osmotic effect in the extracellular fluid (Sangella et al., 1989). Under normal circumstances, renal excretion of sodium is regulated so that balance is maintained between intake and output and ECF volume is stabilized. Hyponatremia is a common problem in patients with advanced cirrhosis. Variety of factors can contribute to the development of hyponatremia in patients with cirrhosis. The most important factor is systemic vasodilatation, which leads to activation of endogenous vasoconstrictors including antidiuretic hormone (ADH); ADH promotes the water retention that is responsible for the fall in serum sodium. Because the increase in ADH secretion (and therefore the degree of water retention) is roughly proportional to the severity of the cirrhosis, the degree of hyponatremia parallels the severity of the hepatic disease and is of prognostic value. A serum sodium concentration below 130 meq/L carries a relatively poor prognosis, whereas values below 125 meq/L often indicate impending hepatorenal syndrome (Arroyo et al., 1994). In patients without liver disease, hyponatremia is associated with a broad variety of neurological manifestations related to the existence of brain edema, such as headache, disorientation, confusion, focal neurological deficits, seizures, and, in some cases, death due to cerebral herniation. The most important factor in determining the severity of neurological symptoms is the rate of fall in serum sodium levels, so patients with acute hyponatremia having a much higher incidence of neurological symptoms than patients with chronic hyponatremia (Adrogue, 2000). Besides hepatic encephalopathy, hyponatremia has also been reported to be associated with other complications of cirrhosis. Specifically, bacterial infections resulting in spontaneous bacterial peritonitis (Follo et al., 1994). Also, Low serum sodium levels are a very common finding in patients with hepatorenal syndrome (Gines et al., 2006) In the majority of patients, the existence of hyponatremia before liver transplantation carries a poor prognosis and is associated with increased risk of renal failure and neurological complications (Londono et al., 2006 & Dawwas et al., 2007). Patients may also develop central pontine myelinolysis after transplantation, (Abbasoglu et al., 1998). It is known that serum sodium in cirrhosis below 130 mmol/l is associated with a median transplant-free survival of less than 6 months (Heuman et al., 2004) The model for end stage liver disease (MELD) is used to predict the outcome of patients with cirrhosis. Incorporation of serum sodium (Na) into MELD may further increase its prognostic ability (Hsua et al., 2012). Aim of the work is to detect the prognostic value of hyponatremia in end stage liver disease (ESLD) patients and its impact on the outcome of these patient.