Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Do you really want to delete this prezi?
Neither you, nor the coeditors you shared it with will be able to recover it again.
Make your likes visible on Facebook?
You can change this under Settings & Account at any time.
Acid Base Disorders
Transcript of Acid Base Disorders
Check Arterial pH
Check Anion Gap
= Na - (Cl + HCO3)
- Acute lung dx
- Chronic lung dx (COPD)
- Opioids, narcotics,
sedatives > Hypoventilation
- Weakening of Respiratory muscles
- Alveolar Hyperventilation
- Pulmonary Embolism, pneumonia, asthma
- Mechanical Ventilation
- Liver disease
- Salicylate toxicity
- Antacid use
Increased Anion Gap
Normal Anion Gap (8-12 mEq/L)
Methanol (formic acid)
Paraldehyde or Phenytoin
Intoxication, Iron tablets, Isoniazid
- Glue sniffing
- Renal tubular acidosis
Is it Acidosis? Metabolic? Anion Gap? Compensated? Corrected?
What are the normal values?
pH = 7.40
pCO2 = 40
HCO3 = 24
pO2 = 100-.25(age)
What are the clinical effects?
- Right shift in oxygen-hemoglobin dissociation curve diminishes the affinity of hemoglobin for oxygen. (Increased oxygen delivery to tissues)
- Depresses CNS
- Decreases pulmonary blood flow
- Impairs myocardial function
- Decreases cerebral blood flow
- Left shift in oxygen-hemoglobin dissociation curve increases the affinity of hemoglobin for oxygen (so decreases oxygen delivery to tissues)
- Tetany, seizures
YoungKey Chung, MSIII
Wayne State University School of Medicine
Acute or Chronic Respiratory Acidosis?
Immediate compensation elevation of HCO3-
Increase of 1 mmol/L for every 10 mmHg increase in PaCO2
Kidneys will slowly adapt
HCO3- increase of 4 mmol/L for every 10 mmHg increase in PaCO2
Acute or Chronic Respiratory Alkalosis?
For every 10 mm Hg decrease in PaCO2, plasma HCO3 decreases by 2 mEq/L
pH increases by 0.08 mEq/L
For each 10 mmHg decrease in paCo2, plasma HCO3- decreases by 5-6 mEq/L
Blood pH decreases by 0.02 mEq/L
WHAT DOES THIS MEAN?
1. Lactate is added
2. H+ from acid is buffered by the bicarbonate system
3. Co2 is formed and removed by the lungs
H+ + HCO3- <-> H2CO3- <-> H2O + CO2
4 .HCO3- levels decrease in the ECF
5. Kidneys reabsorb more HCO3- to maintain pH
DIFFERENT VARIATIONS CAN ARISE:
1. Change in anion gap = Change in HCO3-
1. You add acid, then anion gap increases proportionately!
2. Change in AG is less than HCO3- change
"Normal AG Acidosis + High AG Acidosis"
2. You started with low HCO3-. That is why when you added acid, the HCO3- is lower than the predicted value.
3. Change in AG is greater than HCO3- change
"Metabolic alkalosis + High AG Acidosis"
3. When you have a high AG, the acid is buffered by HCO3-. So, HCO3- decreases. If it doesn't, then you had a lot of HCO3- to start with.
ANION GAP = Na - (Cl + HCO3)
Normal AG = 12 +/- 4
Homeless Man with Altered Mental Status, with a positive UDS:
Na: 158 mEq/L
Ethanol level:0 mg/dL
pCO2: 30 mmHg
pO2: 95 mmHg
% O2 sat: 98%