Acid-Base Balance

Question 0

Intracellular Buffering

Answer 0

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

Question 1

Extracellular Buffering

Answer 1

Occurs instantaneously and responds to metabolic disorders

*Works primarily thru the bicarbonate buffer system

[H+]= 24x Pco2/[HCO3-]

Question 2

Respiratory Buffers

Answer 2

Takes several hours to complete; responds by changing the ventilation rate

Question 3

Renal Buffer System

Answer 3

Takes several days to complete; responds by altering he amount of H+, HCO3-, and NH4+ secreted

Question 4

Metabolic acidosis

Answer 4

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

Question 5

Metabolic Alkalosis

Answer 5

High [HCO3-]

-Develops by ingestion of antacids, vomiting

Question 6

Respiratory Acidosis

Answer 6

High Pco2

Develops from inadequate ventilation (drug-induced) or impaired gas diffusion (pulmonary edema)

Question 7

Respiratory Alkalosis

Answer 7

Reduced Pco2

Develops from stimulation of respiratory centers (drugs, anxiety)

Question 8

Combined Acid-Base Disorders

Answer 8

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