Hypernatremia refers to elevated sodium in your bloodstream in which levels exceed 145 mEq/L. It implies a deficit of total body water relative to total body sodium. Sodium is an electrolyte in your body that aids in many of your bodily functions such as regulating blood pressure and blood volume. Sodium also plays a critical role in the functioning of muscles and nerves; however, too much sodium may have detrimental effects.
Causes of Hypernatremia
There are several causes of hypernatremia. Loss of water in your gastrointestinal tract through diarrhea or vomiting and water loss from the skin after experiencing severe burns or excessive sweating can lead to hypernatremia. If you have kidney disease, hypernatremia can occur when your kidneys cannot reabsorb enough water after filtration. Hypernatremia can also occur from using diuretics to treat high blood pressure, congestive heart failure or edema. Additionally, hypernatremia can occur in diabetics after episodes of polyuria, or excessive urination.
The Elderly and Hypernatremia
According to a June 2000 article in "American Family Physician", hypernatremia is related to age, making the elderly population more susceptible to changes in water balance. A healthy 30 to 40-year-old has a total body water content of 55 to 60 percent. By age 75 to 80, a man's total body water content declines to 50 percent and in elderly women, it declines even more. In a healthy individual, water intake and water losses are balanced; if losses exceed intake, it stimulates thirst. The thirst response decreases with age along with renal function, concentrating abilities and hormonal modulators of salt and water, leading to a higher risk for dehydration and hypernatremia in the elderly.
Symptoms of Hypernatremia
The first symptom of hypernatremia is usually thirst; nausea and headache may follow. Lethargy and weakness can occur as hypernatremia persists and in severe cases, coma and respiratory arrest can follow, leading to death. When there is a decrease in the water content in your brain cells, they shrink and you may experience symptoms of irritability, restlessness, muscular twitches or spasms and seizures. In the brain, the shrinking of the cells can lead to traction on blood vessels, eventually leading to hemorrhage.
Hypernatremia Prevention
Replacement of water is the main goal of hypernatremia treatment. Drinking water is effective in people with no gastrointestinal issues, but with those who cannot drink due to vomiting or mental status changes, IV hydration is the alternate plan. To prevent hypernatremia, avoid salty foods, processed foods such as cured meats, canned soups and vegetables, and fast food. Make sure you drink plenty of water during exercise and also when you are taking diuretics. Healthy adults should limit sodium intake to no more than 2,300 mg a day, while individuals with high blood pressure should consume no more than 1,500 mg a day and those with congestive heart failure or kidney disease should have even less. One teaspoon of table salt contains 2,300 mg of sodium.
