Dehydration

Introduction Loss of water, also known as dehydration, actually refers to the loss of body fluids, which is a symptom of metabolic disorders. In severe cases, it can cause collapse and even life-threatening. It is necessary to rely on infusion to replenish body fluids. Most of the water is lost with the loss of electrolytes, especially sodium ions, which is rare in water loss.

Cause

Dehydration is caused by insufficient water intake and/or excessive loss. Loss of sodium, potassium and other electrolytes is often lost in water loss. Generally, in the pediatrics, water loss is caused. The common causes are diarrhea, vomiting or severe milk insufficiency, gastrointestinal malabsorption and high temperature, severe exercise, high fever and other large sweating. Open treatment loses a large amount of hypotonic fluid. Excessive ventilation, tracheotomy, etc., significantly increase the amount of water exhaled by the lungs (2 to 3 times).

an examination

Related inspection

Central venous pressure measurement (CVP) electrocardiogram

Clinically, children have dry skin mucous membranes (the lips are easier to see), skin elasticity is reduced, eye sockets, sacral depressions, little or no tears when crying, less urine, mental wilting or irritability. In severe cases, there are some manifestations of shock. Loss of water is a common disease, the urine specific gravity is increased, the blood sodium concentration is >145mmol/L, the hypertonic dehydration, the blood sodium <130mmol/L is called hypotonic dehydration, and the water-sodium ratio is consistently called isotonic dehydration. Increased white blood cell count, increased hemoglobin, elevated BUN, Cr, etc. According to clinical symptoms, it is not difficult to diagnose.

Differential diagnosis

Differential diagnosis of water loss:

Dehydration can be divided into hypertonic water loss, hypotonic water loss and isotonic water loss according to its severity.

Hypertonic water loss: also known as water loss and water loss, that is, more water loss than salt loss, blood sodium concentration greater than 150mmol / L. Most of this situation is caused by a large amount of water loss caused by high temperature, excessive sweating or high fever, which cannot be replenished in time. As the osmotic pressure of extracellular fluid increases, the secretion of vasopressin increases, so patients have obvious symptoms such as thirst and oliguria. Patients with mild hypertonic water loss can be relieved if they can drink water early. In the case of severe conditions, treatment may be carried out by instilling a glucose solution having a mass fraction of 5% into the patient.

Hypotonic water loss: also known as salt-deficient water loss, that is, salt loss is more than water loss, blood sodium concentration is less than 130mmol / L. Most of this is due to severe vomiting, diarrhea, major bleeding or extensive burns, resulting in a large loss of water and salt, which was not caused by timely replenishment. As the osmotic pressure of the extracellular fluid is reduced and the secretion of vasopressin is reduced, the patient's urine volume is increased and there is no thirst, which easily leads to the illusion of no water loss. This can be treated by introducing physiological saline into the patient.

Isotonic water loss: also known as mixed water loss, that is, the degree of water loss and salt loss is similar, the blood sodium concentration is 130mmol / L to 150mmol / L. This type of dehydration is the most common in the clinic. For example, most of the water loss caused by vomiting and diarrhea falls into this category. This can be treated by administering physiological saline to a patient and a glucose solution having a mass fraction of 5%.

When rehydrating patients with dehydration, special attention should be paid to the different liquids according to the above three different water loss conditions, the degree of water loss of the patients, and the presence or absence of acidosis.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.