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please someone help me understand these & the difference between metabolic acidosis & respiratory acidosis. please

Specializes in Emergency Department.

First, they both deal with blood pH being acidic. That's the easy part. Next, tell us what you know about this subject so we know what we have to work with, what to teach, and to reinforce. Most of us are willing to help you, but we're going to help you self-teach the right stuff so it sticks better than if we spoon feed you.

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.

Tell me what you think so I can get a feel for what you need.

Specializes in Inpatient Psychiatry.

OK, here's how I figure it (and I apologize for the impending crudeness).

You have three main values: pH (7.35-7.45), Bicarb/HCO3 (22-29), and Carbon Dioxide/CO2 (35-45).

If it's metabolic, the main consideration is HCO3. If it's respiratory, the main consideration is CO2.

So let's say you hold your breath. O2 transport is inhibited, which means that your CO2 rises. The whole point of respiration is to eliminate CO2. When CO2 goes up, that equals respiratory acidosis. A major risk factor of respiratory acidosis include hypoventilation, because your body is not blowing off enough carbon dioxide.

OK, metabolic acidosis is more fun. Let's say you have norovirus, and are suffering from epic diarrhea. A large amount of bicarb (HCO3) is in your gut. When it is gone, and your bicarb (which is an alkaloid) is diminished, you develop metabolic acidosis. I remember it as "out the ass, assidosis." Now, if it was the other way, and you were vomiting, you would lose your stomach's acidity, creating metabolic alkalosis.

Hope that helps.

Specializes in Med-Tele; ED; ICU.

In respiratory acidosis, the rise in hydrogen ion concentration is due to the body's inability to dissipate carbon dioxide via pulmonary ventilation.

In metabolic acidosis, the rise in hydrogen ion concentration is due to some metabolic disturbance of which there are many but in general reflect an overproduction of some organic acid, an ingestion whose byproduct is an organic acid, or impaired/insufficient excretion of hydrogen ions by the kidneys.

Specializes in Family Nurse Practitioner.

Metabolic has to do with the kidneys and digestive system and respiratory has to do with the lungs and respiratory center in the brain.

Think about buffers for each of these systems. That is the difference between the two types of imbalances.

Specializes in Pedi.
OK, here's how I figure it (and I apologize for the impending crudeness).

You have three main values: pH (7.35-7.45), Bicarb/HCO3 (22-29), and Carbon Dioxide/CO2 (35-45).

If it's metabolic, the main consideration is HCO3. If it's respiratory, the main consideration is CO2.

So let's say you hold your breath. O2 transport is inhibited, which means that your CO2 rises. The whole point of respiration is to eliminate CO2. When CO2 goes up, that equals respiratory acidosis. A major risk factor of respiratory acidosis include hypoventilation, because your body is not blowing off enough carbon dioxide.

OK, metabolic acidosis is more fun. Let's say you have norovirus, and are suffering from epic diarrhea. A large amount of bicarb (HCO3) is in your gut. When it is gone, and your bicarb (which is an alkaloid) is diminished, you develop metabolic acidosis. I remember it as "out the ass, assidosis." Now, if it was the other way, and you were vomiting, you would lose your stomach's acidity, creating metabolic alkalosis.

Hope that helps.

I've read this post twice and both times LOL'd. My boyfriend keeps asking me what I'm laughing at.

Specializes in Med-Tele; ED; ICU.
OK, metabolic acidosis is more fun. Let's say you have norovirus, and are suffering from epic diarrhea. A large amount of bicarb (HCO3) is in your gut. When it is gone, and your bicarb (which is an alkaloid) is diminished, you develop metabolic acidosis. I remember it as "out the ass, assidosis." Now, if it was the other way, and you were vomiting, you would lose your stomach's acidity, creating metabolic alkalosis.

I love your mnemonic.

Here's mine: If it's going out the upper end of the GI tract, the pH goes up; if it's going out the low end, the pH goes down...

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