A patient has an arterial blood gas done in the ER: pH 7.51, PCO2 49, PO2 85, HCO3 35. Which of the following describes this ABG?

Partially compensated metabolic alkalosis


•Partially compensated metabolic alkalosis is correct because there is an increase in PH (alkalosis) and an increase in HC03 (metabolic origin).  PC02 is also elevated which tells us the lungs are attempting to compensate, but have not yet fully compensated. 

Respiratory Acidosis:
•Respiratory system is the cause
•Increase in PCO2, decrease in pH
•Compensation - Kidneys reabsorb Bicarb (HCO3)

Metabolic Acidosis:
•Caused by loss of bicarb or a build up of acids - Lactic acidosis, diarrhea, renal failure, ketones, ammonium intoxication. Not caused by respiration.
•HCO3 decreases, pH decreases
•Compensation - hyperventilation to eliminate CO2

Respiratory Alkalosis:
•Caused by excessive ventilation
•Decrease in PCO2, increase in pH
•Compensation - Kidneys excrete HCO3

Metabolic Alkalosis
•Acid (H+) lost from emesis, diuretics. Retention of HCO3 from medications, hyperaldosteronism
•Increase in HCO3, Increase in pH
•Compensation - Repiratory centers are not stimulated, this leads to hypoventilation and CO2 retention

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