hypertonic dehydration
Introduction
Introduction to hypertonic dehydration Hypertonic dehydration refers to the simultaneous loss of water and sodium, but the lack of water is more than the lack of sodium, so the serum sodium is higher than the normal range, the extracellular fluid is hyperosmotic, and when the water shortage is more than sodium deficiency, the extracellular fluid osmotic pressure Increased, increased secretion of antidiuretic hormone, increased reabsorption of water by the renal tubules, decreased urine output. Aldosterone secretion increases, and sodium and water reabsorption increases to maintain blood volume. If the water shortage continues, the extracellular fluid osmotic pressure is further increased, and the intracellular fluid is moved to the outside of the cell. Eventually, the degree of water shortage in the cell exceeds the degree of water shortage in the extracellular fluid, and brain water deficiency may cause brain dysfunction. The treatment is to eliminate the cause, so that the patient no longer loses fluid and replenishes the lost fluid. Oral as much as possible oral, can not be orally administered intravenously with 5% glucose or hypotonic saline solution. The method of supplementing the amount of fluid lost is to estimate the degree of water deficit based on clinical performance. Precautionary measures should pay attention to the active rehydration of the above patients. At the same time of rehydration, attention should be paid to the supplement of electrolytes, which can reduce the disease. basic knowledge The proportion of illness: 0.35% Susceptible people: no specific population Mode of infection: non-infectious Complications: shock
Cause
Hyperosmotic dehydration cause
There are:
Insufficient water intake (35%):
Such as trauma, coma, esophageal disease, difficulty swallowing, can not eat, critically ill patients with insufficient water supply, nasal feeding hypertonic diet or infusion of a large number of hypertonic saline solution. Mainly seen in the following situations:
1, can not or not drink: such as oral, pharyngeal and esophageal disorders, patients with frequent vomiting, comatose patients or extremely debilitated patients.
2, thirsty dysfunction: hypothalamic lesions can damage the thirst center, some patients with cerebrovascular accidents will also lose thirst.
3, the water source is cut off: such as desert lost, sea crashes.
Under the above circumstances, the skin is continuously inhaled by the skin and the water is not sensitive, causing dehydration more than loss of sodium, and increasing plasma osmotic pressure.
Excessive water loss (35%):
Not replenished in time, such as high fever, excessive sweating, extensive burns, tracheotomy, long-term exposure of internal organs during chest and abdomen surgery, diabetes coma. Including simple dehydration and loss of water more than loss of sodium, that is, loss of hypotonic liquid.
1, simple water loss: there are skin, respiratory loss of water and kidney loss of water. The former is seen in hyperthermia, hyperthyroidism and hyperventilation, which enhances the lack of evaporation. The latter is seen in the lack of ADH production and release in central diabetes insipidus and renal insipidus syndrome due to the lack of response to ADH in the distal convoluted tubules and collecting ducts. Therefore, the kidneys discharge a lot of water. Since this dehydration occurs at the farthest end of the nephron, most of the pre-sodium ions are reabsorbed in this part, so the patient can discharge 10-15 L of diluted urine per day with only a few mmol of sodium.
2, more water loss than sodium: First, the loss of sodium-containing digestive juice through the gastrointestinal tract, mainly seen in some infants with watery stool diarrhea, stool sodium concentration below 60 mmol / L. Secondly, it is seen that when the sweat is dripping, the hypotonic liquid is lost, which often occurs in a high temperature environment. In addition, when repeated intravenous injection of hypertonic substances (such as mannitol, urea and hypertonic glucose), osmotic diuresis may cause loss of water more than sodium loss due to increased osmotic pressure of renal tubule fluid.
Other factors (15%):
Problems such as differences in the human body.
Prevention
Hypertonic dehydration prevention
Hyperosmotic dehydration is usually seen in patients with chronic diseases, such as large-area skin burns, and a large amount of sweat loss. Because sweat is a hypotonic solution, it loses more water than salt, causing an increase in plasma osmotic pressure. . Therefore, preventive measures should pay attention to the active rehydration of the above patients. At the same time of rehydration, attention should be paid to the supplement of electrolytes, which can reduce the disease.
Complication
Hyperosmolar dehydration complications Complications
The most common complication of this disease is shock.
Symptom
Symptoms of hyperosmotic dehydration Common symptoms Loss of water, illusion, madness, dry lips, dry dehydration, heat, coma, brain cell dehydration, skin elasticity, poor sleepiness
According to different symptoms, hyperosmotic water deficiency is generally three degrees:
1. Mild water shortage: Except for thirst, there are no other symptoms. The water shortage is 2% to 4% of body weight.
2, moderate water shortage: extreme thirst, with fatigue, oliguria, high urine specific gravity, dry lips, poor skin elasticity, eye socket depression, often irritated, water shortage is 4% to 6% of body weight .
3, severe water shortage: In addition to the above symptoms, there are symptoms of brain dysfunction such as mania, hallucinations, slang, and even coma, the water shortage is more than 6% of body weight.
Impact on the body
1, due to loss of water more than loss of sodium, extracellular fluid osmotic pressure increased, stimulate the thirst center (except for those with thirst), prompting patients to find water to drink.
2, in addition to patients with diabetes insipidus, increased extracellular fluid osmotic pressure stimulates hypothalamic osmotic receptors and increases the release of ADH, thereby increasing renal reabsorption of water, decreased urine output and increased specific gravity.
3. The extracellular fluid osmotic pressure can increase the water in the intracellular fluid with relatively low osmotic pressure to the extracellular space. The above three points can make the extracellular fluid get water supplement, so that the osmotic pressure tends to fall back.
It can be seen that during hypertonic dehydration, both intracellular and extracellular fluids are reduced, but because extracellular fluid may be supplemented in several ways, the reduction of extracellular fluid and blood volume is not as obvious as hypotonic dehydration, and shock occurs. less.
4, early or mild patients, due to blood volume reduction is not obvious, aldosterone secretion does not increase, so there is still sodium excretion in the urine, its concentration can also increase due to increased water reabsorption, in advanced and severe cases, due to blood volume Reduced, increased aldosterone secretion and reduced urine sodium content.
5. Increased osmotic pressure of extracellular fluid can cause a series of symptoms of central nervous system dysfunction when brain cells are dehydrated, including lethargy, muscle twitching, coma, and even death. When the brain volume is significantly reduced due to dehydration, the skull and cerebral cortex The increased vascular tone between them can lead to rupture of the vein and local intracerebral hemorrhage and subarachnoid hemorrhage.
6, severe dehydration cases, especially in children, due to the evaporation of water from the skin is reduced, heat is affected, so dehydration heat can occur.
Examine
Hypertonic dehydration
Diagnosis can be made based on medical history and clinical manifestations (a history of water shortage and thirst, poor skin elasticity, and eye socket depression).
Laboratory inspection:
1. High specific gravity.
2. The increase of serum sodium is more than 150mmol/L.
3, red blood cell count, hemoglobin, hematocrit slightly increased.
Diagnosis
Hyperosmotic dehydration diagnosis
Mainly the identification of the degree of dehydration.
1. Mild dehydration: Due to the decrease of water in the body, the child will feel a little thirsty and have urine discharge. The child is generally in good condition. The two eye sockets are slightly trapped, and the skin of the abdomen or the inner thigh is pinched and retracted quickly. .
2, moderate dehydration: children with irritability, irritability, thirst want to drink water, baby looking around for teats, if you get a bottle, will desperately suck, crying when crying less, urine volume and frequency are also reduced, check see the affected The eyes of both eyes are sunken, the tongue is dry, and the skin of the abdominal wall and the inner thigh is pinched and the skin is retracted slowly.
3, severe dehydration: the child is now extremely mentally atrophied, lethargic, and even coma, mouth drinking is very serious, no tears when crying, urine output and urine count is significantly less. Check that the child's eye sockets are obviously sunken, the tongue is very dry, and the skin is retracted very slowly after pinching the abdominal wall and the inner thigh skin.
