Question? ABG analysis

[briansle]

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patient OD on a sedative.

Arterial blood gas analysis

ph:6.8
pco2 80
p02 40
hco3 12

is it uncompensated resp acidosis?

or

resp acidosis and metabolic acidosis?

 

[FIREitUP]

patient OD on a sedative.

Arterial blood gas analysis

ph:6.8
pco2 80
p02 40
hco3 12

is it uncompensated resp acidosis?

or

resp acidosis and metabolic acidosis?

seems like it's both; it's too extreme of a pH drop to just be either. also with a PCO2 that high you would expect the HCO3 to be higher; it's being buffered by another acid (i.e., metabolic acidosis)

 

[GalenAgas]

patient OD on a sedative.

Arterial blood gas analysis

ph:6.8
pco2 80
p02 40
hco3 12

is it uncompensated resp acidosis?

or

resp acidosis and metabolic acidosis?

Equations to Calculate whether compensation is appropriate (what would be expected in a simple acid-base disorder)

Metabolic Acidosis: \/ PaCO2 = 1.5 (HCO3) + 8
Acute REspiratory Acidosis: /\ HCO3 = 0.1 (∆PaCO2)
Chronic Respiratory Acidosis: /\HCO3 = 0.2 (∆PaCO2)

 

[withrye]

patient OD on a sedative.

Arterial blood gas analysis

ph:6.8
pco2 80
p02 40
hco3 12

is it uncompensated resp acidosis?

or

resp acidosis and metabolic acidosis?

With compensation, CO2 and HCO3 move in the same direction. So in compensated respiratory acidosis, you'll see a primary increase in CO2, along with an increase in HCO3 in an attempt to buffer the acid. (Remember, normal HCO3 is 22-26). Similarly, with something like metabolic acidosis, you'll see a drop in HCO3 with an attempted drop in CO2 (seen on physical exam as hyperventilation).

Here, we see both a rise in pCO2 and a drop in HCO3. This reflects two acidotic processes (respiratory and metabolic) that result in a profound acidemia.