Feeling Acidic
Name 2 things that can cause respiratory acidosis (think specific)
Airway obstruction, acute/chronic lung disease (COPD/asthma), opioids, sedatives
What causes respiratory alkalosis and how does PCO2 change
Hyperventilation, PCO2 decreases
This is the normal range for the anion gap
8-12 (B&B and first aid says 12+/- 4 is normal range)
What IV fluid is typically used to treat chloride-responsive metabolic alkalosis
Normal Saline
An aspirin overdose causes this type of acid-base disorder
What is a mixed acid-base disorder
Why does salicylate accumulation lead to metabolic acidosis
Salicylates uncouple the ETC, inhibiting the citric acid cycle, leading to accumulation of lactate, pyruvate, and ketoacids
Name 3 common causes of respiratory alkalosis
Any of these three: anxiety, pain, pregnancy, tumor, PE, early salicylates, hypoxemia (high altitude)
This is the anion gap equation
AG = Na -(Cl + HCO3)
What is the main treatment for a patient with CKD who has metabolic acidosis
Sodium bicarbonate
This TB medication can cause seizures and lactic acidosis when overdosed
What is isoniazid
This molecule is primarily responsible for the anion gap
What is negatively charged albumin
What test will help us determine the cause of a metabolic alkalosis
Bonus: Name 2 causes that would give us a low test result for this test
urinary chloride levels
<20 chloride levels will be seen in vomiting and antacid use
This enzyme is responsible for the separation of carbonic acid into water and carbon dioxide
Bonus: What medication inhibits this enzyme and causes normal AG metabolic acidosis
Carbonic Anhydrase
Bonus: Acetazolamide
Why can`t we rely on hyperventilation alone to treat metabolic acidosis
Because compensatory mechanisms can not fully return the pH to normal
This is the reason patients have hyperventilation following aspirin overdose
Stimulation of the respiratory center in the medulla
These are the two main urine buffers used to excrete excess H+ during acidosis
Di-hydrogen Phosphate buffer (H2PO4-) and Ammonium (NH4+)
Why does vomiting lead to metabolic alkalosis
Vomiting results in the loss of acidic gastric secretions, which are rich in HCL. Loss of H+ leads to a buildup of HCO3 in the blood
Explain why we are able to have a normal vs high anion gap metabolic acidosis
Normal anion gap metabolic acidosis -> Cl- is being increased in the absence or loss of HCO3
High Anion gap -> increased presence of acids are neutralizing the charge, but arent accounted for in the AG equation
What is the main reason we give potassium prior to giving insulin in a DKA patient
To prevent hypokalemia-induced arrhythmias due to insulin mediated potassium movement into cells
Mark's overdose caused a high anion gap due to accumulation of these
Organic acids (lactate/ketoacids)
This condition causes a type 2 hypersensitivity reaction, and can cause respiratory muscle weakness, leading to respiratory acidosis
What is Myasthenia Gravis
Explain contraction alkalosis
Alkalosis due to volume depletion -> RAAS activation -> H+ excretion and HCO3 reabsorption
This equation is used in metabolic acidosis to determine if there is a secondary metabolic acidosis also happening at the same time
Delta-Delta equation
What treatment would be appropriate for a patient with metabolic alkalosis caused by hyperaldosteronism
A mineralocorticoid receptor antagonist (like spironolactone)
These two toxic alcohols cause high anion gap metabolic acidosis.
Bonus: What is the treatment to fix the overdose
What are Methanol and Ethylene glycol
Treatment: Give ethanol (to inhibit alcohol dehydrogenase) or fomepizole