Acute hyponatremia becomes symptomatic at -
Ans. is 'b' i.e., < 125 mEq Serum level of sodium at which symptoms develop# Acute <125 meq/L# Chronic < 120 meq/Lo Hyponatremia is commonly defined as a serum sodium < 135 mmol/L (< 135 mEq/L). Neurological symptoms occur at different levels of low sodium, depending not only on the absolute value but also on the rate of fall.o In patients with hyponatremia that develops over hours, life-threatening seizures and cerebral edema may occur at values as high as 125 mmol/L.o In contrast, some patients with more chronic hyponatremia that has slowly developed over months to years may be asymptomatic even with serum levels <110 mmol.Acute or hyperacute hyponatremiao The hyponatremia developed within the previous 24 hours, it is called "acute. "o If the hyponatremia developed over just a few hours due to a marked increase in water intake (self-induced water intoxication, as may be seen in marathon runners, psychotic patients, and users of ecstasy), it is called "hyperacute. "Chronic hyponatremiao If it is known that the hyponatremia has been present for more than 48 hours, or if the duration is unknown (such as in patients who develop hyponatremia at home), it is called "chronic. "Mild to moderate hyponatremiao Mild hyponatremia is usually defined as a serum sodium concentration between 130 and 135 meq/L.o Moderate hyponatremia is often defined as a serum sodium concentration between 121 and 129 meq/L.Severe hyponatremiao Severe hyponatremia can be defined as a serum sodium of 120 meq/L or less.Symptoms of hyponatremia Absent symptomso Patients with hyponatremia are frequently asymptomatic, particularly if the hyponatremia is chronic and of mild or moderate severity (ie, serum sodium >120 meq/L).o However, such patients may have subclinical impairments in mentation and gait.Mild to moderate symptomso Mild to moderate symptoms of hyponatremia are relatively nonspecific and include headache, nausea, vomiting, fatigue, gait disturbances, and confusion.o In patients with chronic hyponatremia (ie, >48 hours duration), these findings are not associated with impending herniation; however, in patients with more acute hyponatremia, such symptoms should be considered ominous and may evolve without warning to seizures, respiratory arrest, and herniation.Severe symptomso Severe symptoms of hyponatremia include -# Seizures# Obtundation# Coma# Respiratory arrest.
< 135 mEq
125mEq
< 120mEq
< 1 l0mEq
Fluid & Electrolyte