metabolic and respiratory acidosis alkalosis

[sarda]

hi
someone please explain me how to differentiate between respiratory and metabolic(acidosis/alkalosis)when values like ph pco2....are given
thanks

[AUCMD2006]

use this formula:

Ph=HCo3/Co2

bicarb abnormalities are metabolic carbon dioxide abnormalities are respiratory. for quick look on tests just write the formula out with arrows pointing the direction of the aberrant lab value.

acidosis with low bicarb=metabolic loss somewhere like kidney or GI bicarb loss

acidosis with low Co2 is increase in Co2 for whatever reason like low resp rate

alkalosis with increase in bicarb metabolic

alkalosis with decrease in Co2 respiratory like high resp rate

once you get confortable with the basics you can try mixed and compensated disorders (hint:quick arrow diagram shows both bicarb and Co2 arrows pointing in the same direction so they are abnormal but the Ph maybe normal or very close to normal)

[MDiva]

First decide if it is acidosis or alkalosis, then decide if it is metabolic or respiratory. Here's how.

Acidosis:
1. Look at the pH. Less than 7.4 = ACIDOSIS
2. Look a the PCO2. Less than 40 mm Hg = metabolic; Higher than 40 mm Hg = respiratory.

Alkalosis:
1. Look a the pH. If more than 7.4 = ALKALOSIS
2. Look at the PCO2. Greater than 40 mm Hg = metabolic; Less than 40 mm Hg = respiratory.