Isotonic saline solution

Definition

Isotonic saline solution exhibits the same thing Osmolarity (Particle density) like the blood plasma. It is an electrolyte solution (crystalloidal liquid solution) which contains sodium and chloride (also called NaCl or table salt).

In an isotonic saline solution there are 9g sodium chloride per liter of water (9g / l). Saline is the most widely used infusion solution because it is very cheap and easy to make.

Physical background

There is in the human body sodium in an amount of about 135-145 mmol / l. 97% of them are outside the cell (extracellular), 3% inside the cell (intracellular).

Sodium is an important component for that Build-up of electrical voltage on the cell membranes. There he serves the Forwarding of impulses and is an essential part of our body for muscle work. Sodium fulfills another important role in the Water distribution in the body.

chloride is like sodium an electrolyte and also regulates it Transmission of nerve impulses and intervenes in the water balance. The chloride content in the serum is 98-109 mmol / l. Read about this: Chloride in the blood

Composition and manufacture

Isotonic saline solution is made up of 154 mmol / l sodium and 154 mmol / l chloride. This is the concentration of sodium and chloride ions in isotonic saline solution significantly higher than in the body. This higher dose is necessary because not only sodium and chloride are in the body Osmolarity Determine (particle density) of the blood. The Osmolarity the resulting solution is about 309 mOsm / l and you PH value is between 4.5 and 7.0.

Sodium chloride (Table salt) is used in the manufacture in distilled water (purified water) given. You can say that 1 liter of 0.9% saline solution exactly 9 grams Sodium chloride (Table salt) included.

application

Isotonic saline solution can be used as Carrier solution or Thinners used for medication. Furthermore, it is used in everyday clinical practice Hold open or flush used by venous access, catheters or wounds. The eyes and nose are also rinsed with saline solution.

The Rehydration is another area of ​​application for isotonic saline solution. Here, severely dehydrated patients are given saline to treat a Volume substitution (Restoration of the water content in the body).

The saline solution can also be used to inhalation be used. It serves to moisten and clean the Mucous membranes. This effect can cause the Mucus loosened and coughed up more easily can be. Before bowel surgery or colonoscopy can saline as an enema can be used to clean (see also: Colonoscopy - preparation).

Read detailed information on the subject inhalation

effect

First, the isotonic saline solution accumulates in the Interstitium (Space between the tissue). About 2/3 of the Extracellular space (Space outside the cells) are created by the Interstitium certainly. Only a little of the supplied volume remains intravascularly (located in the blood) what does it mean only very briefly hemodynamic (flowing in blood) effective is.

Side effects and risks

There are very few side effects and risks known for isotonic saline solution. The ingestion is Safe for pregnant women and children. There are no known interactions with other drugs.

At Tendency to water retention It is not recommended to use isotonic saline as an infusion. With caution, saline should also be used Kidney dysfunction (see renal insufficiency), high blood pressure, Cardiac dysfunction (please refer Diseases of the heart) or Water retention in the lungs be used.

Becomes isotonic saline solution excessively or too quickly given it can become a Hypernatremia (too much sodium in the blood) and Hyperchloremia (too much chlorine in the blood). Large amounts of infusion solution can cause a Hyperhydration (too much water in the body). The Hyperhydration represents a absolute contraindication represent.

Read more about hypernatremia here