Saturday, September 1, 2007

Saturday September 1, 2007
Recalling Winters formula


Just to recall some basics, the easiest way to find the compensation CO2 should have for metabolic acidosis is through winters formula. You need HCO3 level from metabolic profile (BMP or Chem-7) and PCO2 from ABG (arterial blood gas). Winters formula is


PCO2 = HCO3 x 1.5 + 8


example:
if your HCO3 level is 12, PCO2 should be


12 x 1.5 + 8 = 18 + 8 = 26 (+/- 2)


If its above 26 +/- 2 means there is a probability of superimposed respiratory acidosis, and if its below 26 +/- 2, means there is a probable compensatory respiratory alkalosis.


Related: ppt presentation on
Acid Base Analysis from Don S. Howard M.D. (rcsw.org)