What functions do the electrolytes do in the body (Part 3.) ?😤

Finally, here is the last part about the electrolutes. 

Chlorine

Cl^- is one of the most important anions in the extracellular fluid, which can regulating the osmotic pressure and acid-base balance of the cell body.

Chlorine is mainly came from sodium chloride in the food. Therefore, the change of chlorine in the body is basically equaled to the sodium. However, there is an opposite relationship between the level of chlorine and the level of bicarbonate. It is because the anions in the body also need to be maintained at a certain concentration. As the two most important anions in the body, chlorine and bicarbonate are normally keeping at a balance way.

Normal serum Cl^- is 96-108 mmol/L. Increased serum Cl^- is common in hypernatremia and high chlorine metabolic acidosis.

In clinical, decreased serum Cl^- is more common and its cause is insufficient intake or increased loss of sodium chloride.

Read More

What functions do the electrolytes do in the body (Part 2.) ?😤

This time will talk about the other important electrolytes in the body: 

Sodium

Na⁺ is the main cation in the extracellular fluid, and it plays a vital role in maintaining many important physiological activities in the body, such as maintaining the osmotic pressure of the extracellular fluid. 

Adult normal serum sodium is 135.0-145.0 mmol/L. Changing the concentration of Na⁺ in the extracellular fluid may caused by changes in the content of sodium and water, so sodium balance disorders are often accompanied by water balance disorders.

The balance of Na⁺ is mainly regulated by changes the volume of extracellular fluid and the concentration of plasma sodium. When the volume of extracellular fluid decreases or the concentration of plasma sodium decreases, it can activate the renin-angiotensin-aldosterone system to promote the reabsorption of Na⁺.

When the amount of extracellular fluid or the concentration of Na⁺ increases, it can lead to increase secreting the natriuretic peptides, reduce the re-collection of Na⁺ by the kidneys, increase sodium excretion, and cause increasing urine output and promote the water excretion.

Read More

What functions do the electrolytes do in the body (Part 1.) ?😤

Electrolytes have the ability to maintain the osmotic pressure of body fluids the normal distribution of body fluids. There are composed of various anions and cations. Potassium, sodium, and chlorine are the three important electrolytes that are most relevant to the diseases and are most closely connected to the patient's life. Firstly, let's talk about potassium and the others will talk in the next two issue.

Potassium

Potassium is the most important cation distributed in the intracellular fluid. It has important physiological functions in maintaining the osmotic pressure of the intracellular fluid, acid-base balance, and maintaining the irritability of muscles and nerves.

1. Normal blood K⁺ concentration

The normal concentration of serum  K⁺  is about 3.5-5.5 mmol/L, the plasma K⁺ is about 0.5 mmol/L lower than the serum K⁺, because when the blood coagulates, K⁺ in platelets and other blood cells will release a few number to the serum.

2. Hyperkalemia and its causes

    a.) The cells are dismantled and potassium ions are forced to flow out to the external fluid. 

The K⁺ concentration of the intracellular fluid is 150.0 mmol/L, which is about 40 times the serum K⁺ concentration. When tissue cells are destroyed (such as    large-area burns, crush injuries), the K⁺ ions in the cells will be flow out to the serum, it result the increasing in blood K⁺. If the upper limit (5.5 mmol/L) is exceeded, it is hyperkalemia. It can lead to heart block, circulatory failure, cardiac arrest in diastole and finally die. 

There are some reasons lead to hemolysis. It can cause false increasing in blood K⁺ which is quite common. Therefore, when the samples with elevated K⁺, it is necessary to check whether the patient's sample is hemolyzed.

    b.) Potassium ions from the outside

Too much K⁺ input from the outside can also cause hyperkalemia, such as the input of a large amount of potassium solution or a large amount of stored blood.

    c.) In acidosis, potassium ions are used to exchange protons

Based on the acid-base balance,  in acidosis, there are many pumps on the cell membrane that can pump a H⁺ of the external fluid into the cell, and then pump a K⁺ out in addition to the regulation of lungs and kidneys. Therefore, patients with acidosis are often accompanied by hyperkalemia. Similarly, when patients have hyperkalemia, there will be a reverse operation, K⁺ is pumped back, and H⁺ is pumped out, and acidosis occurs. Interestingly, hyperkalemia not only leads to metabolic acidosis, but also abnormal alkaline urine.

3. Hypokalemia and its causes

Hypokalemia is also very common in clinical. In hypokalemia, patients may have mental abnormalities, increased heart rate, heart failure, and cardiac arrest in systole. The main causes of hypokalemia are insufficient intake, excessive loss, and potassium from outside the cell into the cell.

Glucose and insulin can drive potassium into the cell. When too much glucose with insulin is input, insulin promotes glucose to enter the cell then synthesize glycogen, it also brings potassium in.

OH^- also has this ability. In alkalosis, H⁺ is needed to neutralize, it pump H⁺ out of the cell and K⁺ back to the cell. Alkalosis is accompanied by hypokalemia, which can also lead to metabolic alkalosis and abnormal aciduria.

Read More