Discuss respiratory compensation for metabolic acidosis

Question

can anyone answer my question, please?

Answer 1

Metabolic acidosis basically means the body is too acidic due to metabolic processes, such as what occurs with high blood sugar and ketoacidosis, kidney disease, drug overdose, etc.

 

The kidneys and the lungs work together to keep the blood pH between 7.35 and 7.45 - slightly basic. Neutral for the blood is 7.4, so anything above 7.4 is considered basic, and anything below 7.4 is considered acidic, as far as blood pH.

 

When metabolic acidosis occurs, with a pH dropping below that 7.4 value, the lungs kick in to compensate to bring that pH back toward 7.4. The lungs help to adjust pH upward or downward in response to what the kidneys are doing with the pH by getting rid of, or hanging on to carbon dioxide, CO2. Think more carbon dioxide, more acidic; less carbon dioxide, more alkaline or basic. We say that when more carbon dioxide is being eliminated than usual, the body is "blowing off" this carbon dioxide, that is, getting rid of acid. This results in a compensatory rise in blood pH to bring the pH back toward that 7.4 midpoint.

 

Conversely, if the lungs needed to compensate for a more basic or alkaline pH, they would "hang on to" or "retain" carbon dioxide. This looks like someone whose breathing is more slow or shallow. You might see shallow respirations in someone who has been vomiting a lot and dehydrated with the result of metabolic alkalosis and a decrease in bicarbonate, HCO3.

 

Please note: the term, hyperventilation can only be accurately used to describe a decreased carbon dioxide level. It is not a sign that we can observe by watching someone's respirations. When we see shallow breathing, we note that we observe "shallow" respirations. If respirations are slower than normal, we record the rate. We could also use the term, "bradypneic." If someone is breathing more rapidly than normal, we document that they are "tachypneic," not that they are "hyperventilating."

 

This is a complicated subject that a lot more could be written on. I hope this helps!

 

Answer 2

Hussain,

 

The body compensates for the lower ph caused by increased arterial pCO2 by hyperventilating.  The increase in ventilation causes a drop in arterial pCO2 consequently inhibiting the ventilatory response reestablishing blood ph homeostasis.  This compensation process begins almost immediately when the body detects abnormal blood ph levels but can take 12-24 to maximally compensate.

 Hope this helps.

Bill N