Hypernatremia in ICU Patients With Hepatic Encephalopathy Is Associated With Worse Outcomes

Abstract

Introduction: Hepatic encephalopathy (HE) is a reversible neuropsychiatric disturbance seen in up to one-third of patients with liver cirrhosis. HE is commonly treated with lactulose, which like many other laxatives, can cause dehydration and various electrolyte abnormalities including hypernatremia. These disturbances, in turn can paradoxically worsen HE and lead to further complications. In critical care, hypernatremia has been linked to increased mortality in the general ICU patients. However, the prevalence and importance of hypernatremia in ICU patients with HE treated with lactulose is not widely known. Methods: We conducted a retrospective single-center observational study to determine the prevalence of hypernatremia in medical ICU patients admitted with HE and to determine patient outcomes. We identified 157 patients who met the inclusion criteria for the study which included age>18, admission to medical ICU and treatment for HE with lactulose. Hypernatremia was defined as serum sodium more than or equal to 150 mEq/L. Results: Our study included 108 (68%) male and 49 (31%) female patients. Average age was 55.8+/-10.6. Majority of patients were Caucasian (89%) and 68% had a history of alcohol abuse. 53% of patients developed Na > 145 during their admission, 33% had Na> 150, and 5% had Na> 160 mEq/L. Average MELD-Na scores were comparable among patients with and without hypernatremia 26.1+/-8.4 and 27.3+/-8.7 (P=0.22). In hospital mortality was higher in patients with hypernatremia (48% vs 37%) although it was not statistically significant (P=0.18). However, there was a statistically significant difference between length of ICU stay and length of hospital stay (20.8 +/- 20.6 vs 9.4 +/-11.2, p < 0.001) and (33.2 +/- 28.2 vs 16.4 +/- 16.3, P < 0.001), respectively. Additionally, a significantly higher proportion of patients with hypernatremia required intubation during their hospital stay (81% vs 47%, P < 0.01). Conclusion: Hypernatremia is common among ICU patients with HE. Furthermore, hypernatremia is associated with higher rates of intubation and longer lengths of hospital and ICU stay. Due to the retrospective nature of this study, we cannot determine whether hypernatremia serves as a marker for worse outcome or whether it is the cause. Further, prospective studies are necessary to further elucidate the relationship between hypernatremia and outcomes and to determine whether correction of serum sodium plays any role in the improvement of such outcomes.Figure: Patient demographics. Numbers in () represent percentages.Figure: Hypernatremia is associated with worse outcomes in ICU patients with hepatic encephalopathy. Numbers in () represent percentages. LOS =Length of stay. Na=serum sodium level in mEq/L.