Hyponatremia and Mortality: How Innocent is the Bystander?

[摘要] For those who are not electrolyte enthusiasts, hyponatremia can be a frustrating disorder. Dealing with hyponatremia means considering various and often opposite scenarios. Does the patient have hypovolemic, euvolemic, or hypervolemic hyponatremia? Is it acute or chronic? Symptomatic or asymptomatic? Do I want to correct rapidly or more slowly? Shall I give normal saline, hypertonic saline, or water restriction? And—every resident's nightmare—which of the impossible formulas shall I use to calculate the correction rate? These challenges may be the reason that the management of hyponatremia is still suboptimal (1–3). This is worrisome not only because hyponatremia counts as the most common electrolyte disorder in hospitalized patients but also because it is associated with increased mortality. The association between hyponatremia and mortality has been demonstrated in numerous studies (4–9), but causality has been difficult to prove. Therefore, two possibilities remain (Figure 1): (1) Hyponatremia is a direct cause of death, or (2) severe underlying disease is the cause of death and hyponatremia is merely another complication of this underlying disease.

[学科分类] 泌尿医学

[关键词] Bone marrow necrosis;Sickle cell disease;Hyperhemolysis syndrome