Lecture 4-5 (blood gas analysis) Flashcards
What are electrolytes
Charged ions which are in solution in all body fluids
Main extracellular cation
Sodium (Na+)
Main intracellular cation
Potassium (K+)
Main intracellular anions
Protein
Phosphate
Main extracellular anions
Chloride (Cl-)
Bicarbonate (HCO3-)
Normal hydrogen ion concentration
35-45nmol/L
pH 7.35-7.45
What is a buffer
A weak acid in solution with its conjugate base.
Can absorb H+ or OH- ions
What is the most important buffer in the ECF
Bicarbonate
In normal arterial blood what is the ratio of HCO3- concentration to H2CO3 (carbonic acid) concentration
20:1
Where are hydrogen ions excreted from the body
in the kidneys
Name 4 types of acid base disturbances
Metabolic acidosis (HCO3- affected, pH decreased)
Metabolic alkalosis (HC03- affected, pH increased)
Respiratory acidosis (H2CO3 affected, pH decreased)
Respiratory alkalosis (H2CO3 affected, pH increased)
Anion gap calculation
= Na+ - (Cl- + HC03-)
Reasons for reduced anion gap
Hypoalbuminemia
Bromide intoxication
Multiple myeloma
Lab error
Reasons for metabolic acidosis with a normal anion gap
Administration of chloride containing acids
GIT bicarbonate loss
Inherited.acquired renal tubular defects
Reasons for metabolic acidosis with an increased anion gap
Uremia Ketoacidosis Lactic acidosis Methanol toxicity Ethylene glycol toxicity Salicylate
