Fluids and Electrolytes Acid-Base balance Chapter 18 (2)

Refers to the homeostasis of the hydrogen ion (H−) concentration in the body fluids.

Acid-base balance (also called acid-alkaline balance)

A solution with a high number of hydrogen ions

acid

A solution with a low number of hydrogen ions is an

alkaline (base)

What type of blood is drawn to get the pH balance?

arterial blood is used to determine the body’s pH.

Acid pH numbers

less than 7.35

Alkaline pH numbers

greater than 7.45

Normal pH of venous blood and interstitial fluids

7.35-7.45

A pH of less than 7.35 is

acid

A pH of greater than 7.45 is

alkaline

The normal pH of arterial blood is approximately

7.45

the normal pH of venous blood and interstitial fluid is approximately 7.35

normal blood pH

7.35 and 7.45 is considered

A fatal pH

lower than 6.8 or higher than 7.8

The body has three systems that work to keep the pH in the narrow range of normal:

the blood buffers

the respiratory system

the kidneys.

consist of either a weak acid and its base salt or a weak base and its acid salt.

Blood buffers (also called physiologic buffers)

Carbon dioxide is a potential acid. When it is dissolved in water, it becomes

carbonic acid

In the state of acidosis, the kidneys will

excrete hydrogen and retain bicarbonate

In the state of alkalosis, the kidneys will

excrete bicarbonate and retain hydrogen.

In respiratory acidosis the body attempts to get rid the excess of the excess carbon dioxide by

increasing respirations.

In respiratory acidosis, the kidneys attempt to compensate by

retaining the base substance bicarbonate and eliminating hydrogen.

Treatment for respiratory acidosis is aimed at

improving ventilation.

caused most frequently by hyperventilation secondary to anxiety, pain, fear, and stress

Respiratory alkalosis is

Increased respiratory rate, depth, or both have the potential to cause the loss of excessive amounts of

carbon dioxide,

In respiratory alkalosis The kidneys attempt to compensate by

conserving hydrogen ions and excreting bicarbonate ions,

Symptoms include lightheadedness, numbness and tingling sensation in extremities, tinni-tus, blurred vision, increased heart rate, and irritabil-ity. In extreme cases, confusion, seizure activity, and loss of consciousness may occur.

Respiratory alkalosis

occurs as a result of a gain of hydrogen ions or a loss of bicarbonate

Metabolic acidosis

In Metabolic acidosis, the lungs attempt to compensate by

Hyperventilation increasing the respiratory rate and eliminating more carbon dioxide

Common symptoms include a change in the patient’s level of consciousness, headache, vomiting, diarrhea, anorexia, and cardiac dysrhythmias

Symptoms of metabolic acidosis

when a significant amount of acid is lost from the body or if the bicarbonate level increases

Metabolic alkalosis

The most common causes of _____ _____ are vomiting gastric content (normally high in acid) and pro-longed gastric suction

metabolic alkalosis

depresses the central nervous system, which results in headaches, irritability, lethargy, changes in level of consciousness, and confusion. Changes in heart rate; slow, shallow respirations; nausea and vomiting; and numbness in the extremities

Metabolic alkalosis