In the most common inpatient problems in internal medicine, 2007. Mild to moderate symptoms mild to moderate symptoms of hyponatremia are relatively nonspecific. Hyponatremia defined as a serum sodium level hyponatremia, and pseudohyponatremia. Ensure youre boardexam ready with acps board prep course recordingsa multimedia, selfstudy program that delivers multiple study tools. The efficacy of oral tolvaptan was demonstrated in multicenter trials salt1 and salt2 44, 45 in 448 patients with hyponatremia caused by siadh. Kidney or congestive heart failure, hypothyroidism, cirrhosis, medications, or strenuous exercise without electrolyte replacement can cause hyponatremia. Hyponatremia is defined as a decrease in the serum sodium concentration to a level below 6 mmol per liter.
Fluid restriction is the classical treatment for hyponatremia secondary to syndrome of inappropriate secretion of antidiuretic hormone. A blog made by john schonert, an em pgy3 from west virginia. Hyponatremia is decrease in serum sodium concentration of water relative to solute. Notice how fine the line is between balance and distress there are three ways sodium fluctuations can happen in the body.
Hyponatremia is a low sodium concentration in the blood. Common causes include diuretic use, diarrhea, heart failure, liver disease, renal disease, and the syndrome of inappropriate antidiuretic hormone secretion siadh. Thus, hyponatremia is a measure of water imbalance. A low plasma or serum sodium concentration usually indicates an excess of water relative to total body sodium and potassium. Hyponatremia is a common water balance disorder that often poses a diagnostic or therapeutic challenge. Hyponatremia without hypotonicity can be found in patients with hyperglycemia and in patients who have accumulated exogenous effective osmoles like mannitol, sucrose, maltose, sorbitol, glycine, or radiocontrast. The condition can also be prevented altogether by following certain preventive measures.
Hyponatremia is often iatrogenic in in patients and severe sodium disturbances are associated with considerable morbidity and mortality. Anton helman, march 2015 hyponatremia is the most common fluid and electrolyte disorder encountered in clinical practice and is found in approximately 20% of admissions to hospital. His blog is a collection of the best in em education. Most patients with hyponatremia have hypotonicity, but there are exceptions table 1. According to a study in the new england journal of medicine, percent of nearly 500 runners studied at the boston marathon finished the race in a state of hyponatremia. Subscribe to the weekly updates to get short summaries of the best em on the web for free. May 15, 2004 hyponatremia generally is defined as a plasma sodium level of less than 5 meq per l 5 mmol per l. Hyponatremia may be euvolemic, hypovolemic or hypervolemic. Whereas hypernatremia always denotes hypertonicity, hyponatremia can be associated with. Hyponatremia occurs when the concentration of sodium in your blood is abnormally low. Hyponatremia or low sodium levels in the blood can result in signs and symptoms like headache, confusion, seizures, weakness, restlessness, and muscle spasms. Hyponatremia show notes word format hyponatremia show notes pdf websites that i talked about. Notice how fine the line is between balance and distress.
The vast majority of patients with hyponatremia have hypotonicity, but there are exceptions. Treatment is based on symptoms and underlying causes. A healthy sodium level is between 5 and 145 mmoll and a person is considered to be. Normal plasma contains between 6 and 145 milliequivalents per liter meql of sodium. The varied etiologies of hyponatremia and the multiple formulae for its correction make it a nightmare for the students and physicians alike.
A blog made by john schonert, an em pgy3 from west. There are a few different causes of the condition, but the one of interest to athletes is when dilution of sodium levels in the blood is driven by excessive drinking. The treatment of hyponatremia depends on the time course, severity, and underlying cause of the disorder. However, hyponatremia occasionally may develop in the course of treatment with drugs used in everyday. Hyponatremia endocrine and metabolic disorders merck. Hypertonic saline is used to treat severe symptomatic hyponatremia. Hyponatremia is present when the serum sodium concentration is less than meql mmoll, although some would consider a value less than 5 to be hyponatremic. When and how to treat hyponatremia in the ed canadiem. Proper interpretation of the various laboratory tests helps to differentiate the various types of hyponatremia. However, such patients may have subclinical impairments in mentation and gait. Mild symptoms include a decreased ability to think, headaches, nausea, and poor balance. Hyponatremia, on the other hand, has been blamed for more than a dozen deaths in recent years source.
By definition, hyponatremia occurs when serum sodium levels in the plasma fall below hyponatremia cases ar. Evaluating hyponatremia acid base, electrolytes, fluids. It is one of the common and essential electrolyte abnormalities, which can either be present in isolation or as a resultant complication of the several medical conditions. Treatment varies with the nature of onset acute or chronic, severity and symptoms. Optimal treatment of hyponatremia in clinical practice open access. When the level of sodium in our blood is abnormally low then hyponatremia condition occurred. At the same time, patients may present with electrolyte abnormalities that are asymptomatic and are incidental findings on bloodwork. Many medical illnesses, such as congestive heart failure, liver failure, renal failure, or pneumonia, may be associated with hyponatremia.
Hyponatremia is commonly defined as a serum sodium concentration below 5 meql, but the definition can vary to a small degree in different clinical laboratories. Diagnosis and treatment of hyponatremia inside the silver fridge. Electrolyte imbalances like hyponatremia can be the cause of a variety of vague complaints. It can happen because of certain medical conditions, some medicines you might be taking, or if you drink too much water. Aug 22, 2016 hyponatremia is a medical term describing low hypo blood sodium levels natremia na is the chemical symbol for sodium. Hyponatremia is a medical term describing low hypo blood sodium levels natremia na is the chemical symbol for sodium. Hyponatremia without hypotonicity can be found in patients with hyperglycemia and in patients who have accumulated exogenous effective osmoles like mannitol, sucrose, maltose, sorbitol, glycine, or. A clinical diagnosis chart used to determine the cause of hyponatremia. The term hyponatremia refers to a condition where the blood level of the electrolyte sodium is too low. Causes of hypernatremia involve a net gain of sodium or a loss of free water. Renal loss of electrolytefree water due to ureainduced osmotic diuresis has been described as causative in up to 10%. Hyponatremia, defined as a decrease in serum sodium below 6 mmoll, is a common occurrence in both inpatients and outpatients and can be found in up to 15% of the general hospital populations. Treatment for hyponatremia are diet changes and electrolyte replacement with. Hyponatremia is an imbalance in electrolytes, where there is low serum sodium than the normal level.
Normal range generally falls between 3 to 146 meql, with some variability dependent on individual laboratories. Urinary osmolality was 600 mosml, and urinary sodium was 80 mmoll. Vaptans are used in addition to fluid restriction and sodium chloride administration. Sodium disorders are diagnosed by findings from the history, physical examination, laboratory studies, and evaluation of volume status. Acute and severe hyponatremia cause neurological symptoms necessitating. Nursing mnemonics cyanotic defects hyperkalemia causes beta 1 and beta 2 the 4 ts tetralogy of fallot truncus arteriosus transposition of the great vessels tricuspid atresia hypoxia signs and symptoms fines feeding di. Jun 17, 2019 hyponatremia is defined as a serum sodium level of less than 5 meql and is considered severe when the serum level is below 125 meql. Hyponatremia is a medical condition termed for a low concentration of sodium in the blood serum.
It is generally defined as a sodium concentration of less than 5 mmoll 5 meql, with severe hyponatremia being below 120 meql. Hyponatremia is decrease in serum sodium concentration hyponatremia is important clinically because. Hyponatremia happens when sodium levels in the blood dip below a certain level, often triggered by overhydrating. Hyponatremia is the most common electrolyte abnormality in hospitalized patients, and the syndrome of inappropriate secretion of antidiuretic hormone siadh is the most common cause of hyponatremia in this patient population pseudohyponatremia. Hyponatremia or a low blood sodium level can sometimes be corrected before it causes complications. Successful longterm treatment of hyponatremia in syndrome of. However, many drugs were not included in the investigators. Nov 19, 2016 introduction hyponatremia decrease in serum sodium conc. Clinical assessment of total body water and urine studies help in determining cause and guiding treatment of hyponatremia.
Patients with pseudohyponatremia have normal serum sodium. Hyponatremia that is secondary to siadh is common in legionnaires disease that that which is caused by pathogens. Most patients with hyponatremia have hypotonicity, but there are exceptions. Certain drugs eg, diuretics, antidepressants, and antiepileptics. Hyponatremia is an important and common clinical problem. Hyponatremia causes, algorithm, correction and treatment.
When plasma has large amounts of other osmotically active. In hyponatremia, one or more factors ranging from an underlying medical condition to drinking too much water cause the sodium in your body to become diluted. The guidelines for management of hyponatremia have been revised recently and, in addition new agents vaptans have become available in market for. It should be noted here that, sodium is one kinds of electrolyte which helps to regulate the amount of water thats in and around our cells. Heres an approach to deciding when and how to treat hyponatremia in the emergency department. The nonhypotonic hyponatremias are hypertonic or translocational hyponatremia, isotonic hyponatremia, and pseudohyponatremia. As a result of low sodium, the amount of water in your body rises and causes your cells to swell.
Hyponatremia disease treatment and complication of hyponatremia. There are a few different causes of the condition, but the main one of interest to athletes is when dilution of sodium levels in the blood is caused by excessive drinking. In hyponatremia, one or more factors ranging from an underlying medical condition to drinking too much water cause the sodium in your body to become. Disordered secretion of the pituitary hormone vasopressin alternative name, antidiuretic hormone adh is central to the pathogenesis of hyponatremia for many patients, and this is. No symptoms patients with hyponatremia are frequently asymptomatic, especially if the hyponatremia is chronic and of mild or moderate severity ie, serum sodium 120 meql. Hyponatremia is the most common electrolyte disorder seen in hospitalized patients. Defining the cause of postoperative hyponatremia in the.
Cases of pneumonia are caused by several pathogens that share similar laboratory findings. The prevalence has been reported to be 530% depending on the clinical setting. Management of hyponatremia american family physician. They also presented rare causes of druginduced hyponatremia derived from occasionally reported cases. Renal causes include diuretic excess, renal failure, salt wasting nephropathy, aldosterone deficiency, chronic pyelonephritis, nephrocalcinosis, proximal renal tubular acidosis and ketonuria. Hyponatremia and hypernatremia are classified based on volume status hypovolemia, euvolemia, and hypervolemia. Hyponatremia without hypotonicity can occur in patients with hyperglycemia, in patients who have. May, 2014 hyponatremia, defined as a decrease in serum sodium below 6 mmoll, is a common occurrence in both inpatients and outpatients and can be found in up to 15% of the general hospital populations. Sodium is an electrolyte, and it helps regulate the amount of water thats in and around your cells.
The most common causes of postoperative hy ponatremia were hypovolemia 33. Hyponatremia defined as a serum sodium level causes of either asymptomatic or symptomatic hyponatremia. Hyponatremia show notes pdf websites that i talked about. If the sodium in your blood is too low, you have a condition called hyponatremia. Medications such as vaptans may have a role in the treatment of euvolemic and hypervolemic hyponatremia.