Acid-Base Balance Flashcards
Intracellular Buffering
Occurs within a few minutes; largely moves H+ in and out of cells where it is titrated by the phosphate buffer and protein buffer systems
*Compensates for respiratory acid-base disorders
Extracellular Buffering
Occurs instantaneously and responds to metabolic disorders
*Works primarily thru the bicarbonate buffer system
[H+]= 24x Pco2/[HCO3-]
Respiratory Buffers
Takes several hours to complete; responds by changing the ventilation rate
Renal Buffer System
Takes several days to complete; responds by altering he amount of H+, HCO3-, and NH4+ secreted
Metabolic acidosis
Low [HCO3-]
*By calculating the anion gap, you can perform the differential diagnosis
Increases? => Diabetic ketoacidosis, salicylate poisoning, renal failure
Decreases? => Diarrhea, renal tubular acidosis, hypoaldosteronism
Metabolic Alkalosis
High [HCO3-]
-Develops by ingestion of antacids, vomiting
Respiratory Acidosis
High Pco2
Develops from inadequate ventilation (drug-induced) or impaired gas diffusion (pulmonary edema)
Respiratory Alkalosis
Reduced Pco2
Develops from stimulation of respiratory centers (drugs, anxiety)
Combined Acid-Base Disorders
Acidosis: Decreased ventilation can lead to increased Pco2 AND decreased HCO3
- Occurs because of increased anaerobic metabolism i.e. lactic acid production * IRDS, combined respiratory and renal failure
Alkalosis: Hyperventilation with vomiting