pediatric hyponatremia
Introduction
Introduction to hyponatremia in children Hyponatremia is also known as hyponatremia syndrome, low salt syndrome (lowsaltsyndrome) and the like. It is a serious disorder of water and electrolyte metabolism, mainly due to insufficient sodium in the body or excessive water in the body, resulting in sodium deficiency or dilute hyponatremia. At the same time, it is related to the abnormal secretion of vasopressin (ADH) and the production of dilute hyponatremia. This symptom refers to the pathological state caused by the decrease of total sodium in the body. The total exchangeable sodium of the human body is 40-45 mmol/kg. Low-salt syndrome is often associated with hyponatremia, but there is also serum sodium is not low. Conversely, although most of the low-sodium syndrome is accompanied by a decrease in total sodium in the body, there are also normal or increased, clinically measured serum. Sodium is not the total amount of sodium in the body. Low-salt syndrome refers to a decrease in total sodium in the body, which is not strictly equivalent to low-sodium syndrome. basic knowledge The proportion of illness: 0.002% Susceptible people: children Mode of infection: non-infectious Complications: coma, child convulsion, respiratory failure
Cause
Causes of hyponatremia in children
Causes:
Gastrointestinal disorders are the most common and easy to identify. Others caused by brain, kidney and lung diseases are difficult to identify. Gastrointestinal disorders are often caused by improper infusion. Respiratory diseases such as pneumonia and bronchial asthma can cause abnormal secretion of ADH. Cranial brain diseases such as encephalitis, tumors, etc. can cause cerebral hyponatremia, kidney disease often due to long-term avoidance of salt, sodium intake is less, once infection, vomiting and diarrhea, eating less, etc., it is easy to occur this disease, Classification and causes of hyponatremia.
Pathogenesis:
Hyponatremia refers to serum sodium concentration <130mmol / L, generally due to the lack of primary sodium caused by the consumption of sodium in the body or excessive water in the body or the combination of two reasons. Primary sodium deficiency is associated with the inability of the kidney to regulate sodium metabolism. Renal sodium loss is due to the inherent defects in the kidney during sodium regulation. Premature infants are not mature due to the kidney's function of sodium reabsorption. Loss of urine, even when serum sodium concentration is low, due to congenital urethral abnormalities, obstruction, dysplasia, dysplasia or other renal congenital diseases such as medullary cavernous kidney caused by renal salt loss syndrome, It also causes significant loss of sodium in the urine. Mineralocorticoid deficiency caused by insufficient adrenal function is the most common in children with adrenal hyperplasia. Renal sodium salt loss can also be seen in the recovery of acute tubular necrosis. Children who have long-term use of diuretics, and osmotic diuresis with diabetes can also cause loss of renal sodium.
The loss of sodium in extrarenal tissues is often associated with loss of nasogastric digestive juice without timely compensation or loss of gastrointestinal fluids due to gastroenteritis. This type of gastroenteritis is often vomiting and diarrhea. It can cause loss of water in the intestines and more obvious loss of sodium. The hyponatremia caused by the loss of sodium more than the loss of water will be further aggravated after the intake of low solute beverages.
In the hyponatremia caused by decreased nutrient sodium intake, the most common cause is water poisoning syndrome. This type of water poisoning is often found in some formulas that ignore the normal dietary concentration and consume a large amount of sodium with very low sodium content. For small babies, these babies will experience heavier hyponatremia and central nervous system symptoms such as seizures.
Among the various causes of abnormal primary water, vasopressin inappropriate secretion syndrome (SIADH) is the most common. This syndrome may have many causes, but the common feature is that there is no physiological stimuli. Antidiuretic hormone is also secreted. This increased secretion of antidiuretic hormone can lead to increased reabsorption of water by the collecting tube, diluting the extracellular fluid, and ultimately leading to hyponatremia, in children, in those with antidiuresis Among the various abnormalities associated with inappropriate hormone secretion syndrome, complications of acute meningitis are the most common cause.
Hyponatremia caused by excessive water also includes factors of excessive exogenous water, such as intravenous use of diluted or less sodium-containing liquids to treat dehydration, in the presence of hyponatremia and in vivo sodium Abnormal water retention is usually caused by diseases that cause edema, such as nephrotic syndrome and cirrhosis. In these pathological conditions, the movement of water from plasma to interstitial can stimulate the body to produce thirst and release vasopressin. It causes the retention of water and sodium. When the retention of water exceeds the retention of sodium, hyponatremia occurs. Heart failure can also activate the retention mechanism of water and sodium, but the plasma colloid osmotic pressure remains normal.
Prevention
Prevention of hyponatremia in children
Improve medical technology, prevent iatrogenic hyponatremia, such as reasonable rehydration of diarrhea, reasonable diet of children with nephrotic syndrome, etc. For children with infectious diseases, especially severe cases, pay attention to monitoring blood electrolytes and strengthen comprehensive treatment Measures.
Complication
Pediatric hyponatremia complications Complications, coma, convulsion, respiratory failure
He was convulsed, comatose, and severe respiratory failure occurred in severe cases.
Symptom
Symptoms of hyponatremia in children Common symptoms Pale pale irritability, dehydrated skin pattern, low urine heart sound, low blunt blood pressure, drowsiness, convulsions, bloating
Sodium is the main cation of extracellular fluid. Its main physiological function plays an important role in maintaining extracellular fluid volume, osmotic pressure and alkali reserve. It maintains nerve and muscle normal stress, so the following symptoms are caused when sodium is absent.
1. Reduced extracellular fluid volume: poor circulation, shock, such as pale gray, skin pattern, cold limbs, blood pressure, oliguria, etc. It has been reported that due to nephrotic syndrome, long-term avoidance of salt plus merger Infection, causing hyponatremia and death.
2. Release ADH increase: make water retention in the body, or reduce the excess of Zhang liquid, resulting in decreased extracellular fluid osmotic pressure intracellular edema brain cell edema intracranial hypertension; such as listlessness or lethargy and irritability Two eyes gaze, but also convulsions, coma, severe central respiratory failure.
3. Nerve, muscle stress is low: manifested as low muscle tone in the limbs, decreased knee reflex, low heart bluntness, abdominal distension, weakened bowel sounds, etc.
According to the pathophysiology and clinical manifestations of this disease, the symptoms are mainly caused by poor circulation or (brain) cell edema, and the symptoms are divided into four categories; simple water poisoning is caused by dilute hyponatremia; simple low sodium; Both hypotonic dehydration and hyponatremia in water are caused by sodium deficiency hyponatremia. There is no peripheral circulation in the dilute, and the extracellular fluid is reduced in the sodium deficiency, so there is poor peripheral circulation, but poor circulation and The degree of cerebral edema is different.
Examine
Examination of hyponatremia in children
1. Blood test: serum sodium <130mmol / L.
2. Others: depending on the primary disease, the person with diarrhea has a corresponding change in stool examination; the white blood cell count and neutrophils in the peripheral blood of infected people are significantly increased; those with nephrotic syndrome, high blood cholesterol, plasma protein Low and a large amount of proteinuria; cerebrospinal fluid examination of encephalitis has been found.
3. According to clinical needs, choose chest X-ray, brain CT, electrocardiogram and other examinations.
Diagnosis
Diagnosis and diagnosis of hyponatremia in children
diagnosis
According to clinical manifestations and serum sodium <130mmol / L can be diagnosed.
Differential diagnosis
Identification of various types of low-salt syndrome as a reference for the diagnosis of low-salt syndrome.
