pH Value of Blood

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What is the pH Value of Blood?

The pH value of blood of a healthy human being is 7.35 to 7.45. 

The pH value of blood indicates the acidic or alkaline level in the body. The value of pH in the body is an important indicator of the health of a person. The normal pH of blood is essential for the proper functioning of the optimal activity of the body. Hence, because of this the body physiologically balances the blood pH range. The blood pH level normal range is from 7.35 to 7.45 for a healthy person. Thus, from the normal pH of blood of a human, it can be said that the blood is slightly basic. 

How Blood pH is Maintained?

For a human being the pH of blood in human body is very well regulated by maintaining an acid-base balance. It is very essential to maintain this homeostasis. Various factors play their part in regulating the blood pH range. The blood plasma pH depends on the concentrations of CO2, electrolytes and weak acids. There are two main organs, the lungs and the kidney, that are involved in the balancing of the acid-base concentrations. The mechanism by which they do so is:

  • Lungs: They have the most significant role in exchanging gases with the blood. They remove CO2 by the gaseous exchange. The brain regulates the breathing activity and so the brain along with the lungs maintain pH value of blood by regulating the speed and intensity of the breathing. 

  • Kidney: Kidney is involved in the ultrafiltration of the blood and takes away the waste material from the blood and finally excretes them. Thus, in the process, any acid or base present in excess in the blood is removed thus maintaining pH of blood in human body.

Thus, the human body balances what is the pH of blood via respiration, excretion and other metabolic activities.

Why is Blood pH Important?

Any changes that occur in the blood, due to an increase in acidic level (acidosis) or the basic level (alkalosis) is a cause of worry. This can happen due to impaired function of the lungs or the kidneys organs since they are the ones responsible for cleaning the blood of unwanted products. Changes in the normal pH of blood are generally associated with kidney failures. 

Sometimes what is the pH level of blood is affected due to dysfunction of some other organs as well because of which there can be a release of the acidic and basic materials in the bloodstream. Thus, the normal pH of blood is important because it states the healthy state of internal organs of the body, specifically the kidney and the lungs.

Due to changes in the concentration of waste materials such as carbon dioxide, electrolyte and other acidic substances, the concentration of the oxygen dissolved in the blood changes and this, in turn, affects the respiration process of the cell. Once cellular respiration is damaged, the cells begin to die and can result in catastrophic events in the body such as organ failure and subsequent death. Thus, maintaining what is the normal pH of blood becomes extremely important for survival. 

Causes of Abnormal pH Value of Blood

Organ dysfunction especially of the kidneys and lungs result in too high or too low levels of blood pH range. An increase in the acidic or the basic content is also indicative of grave diseases of the heart, lung or kidney and also indicate poisoning, infection, and diabetes.

The conditions of the high and low blood pH range and their causes are explained further.

High pH Value of Blood

High blood pH range is known as alkalosis. Under this condition, the blood becomes more and more basic as the pH goes higher than the normal pH of blood. The following are the reasons for the changes in the blood pH range taking the value higher than what is the normal pH of blood:

  • Excess loss of fluid because of the increase in urination, vomiting, diarrhoea, etc is one of the primary reasons for the value to get a higher pH value of the blood. If noticed, these symptoms are some symptoms of diseases such as cholera, dengue, etc. Thus a temporary illness, in this case, is the reason for the high pH value of the blood from what is the pH of the blood.

  • When kidneys are unable to remove the excess of the alkaline materials due to improper functioning, it can lead to a rise in the pH value of blood.

Low pH value of Blood

Low blood pH range is called acidosis. In this condition, the blood becomes more and more acidic as the pH goes lower than the normal pH of blood. Also, this is more common than alkalosis. The main reasons the normal pH of blood goes lower are given below:

  • In diabetic patients, when the body is unable to produce enough insulin, it can lead to another problem of the release of acidic ketones in the blood. This is called ketoacidosis andis another complication of diabetes.

  • The renal failure of the kidneys because of any disease or deteriorating health leads to metabolic acidosis. 

  • Respiratory diseases such as pneumonia, bronchitis, asthma, chronic pulmonary disease in the lungs can lead to acidosis. 

So, the answer to the question - why is blood pH important? - can be given as Blood pH range is vital for cellular respiration and intake of oxygen by the cells from the blood and also many times to diagnose diseases because these changes occur owing to organ failure because of a variety of reasons, the pH value of blood is an important determinant of the disease condition of the body. 

FAQ (Frequently Asked Questions)

1. What is the pH of Blood?

Ans: The pH value of blood lies between 7.35 to 7.45. Any change, even a minor one in this blood pH range can have severe implications. This pH value of the blood is the representation of a healthy human being. 

2. What Happens When the pH of Blood is Too High?

Ans: When there is high basic content in the blood, the pH value increases more than the normal value. This condition is called alkalosis. This is indicative of the disease conditions such as an increase in urination, vomiting, diarrhoea, etc. Also, when the kidney is unable to clear the basic content from the blood, it results in high blood pH.