PaO2 vs SaO2

Hilarious!...You should have said "Figure it out yourself Mr. PaO2!"....lol

Thank you. Funny, very funny, but could you answer my inquisition please? I'm still not sure what's up.

paulwalkman said:

Thank you for that last mention. Since PaO2 is assumed during routine testing, how would it specifically be tested? Does an arterial blood sample need to be taken to get the ABGs? Early in my career I had a jerk doctor ask me 10 minutes after he wrote an order to put a pt on 3L O2 because her PulseOx was 88ish. I told him the PulseOx and he repeated 3 times successively louder each time "what is the PaO2!!?" I asked "if labs had to be drawn and he yelled back, "No, You go tell me what it is...NOW!" I had to get the charge nurse to talk to him. I just never thought to ask again.

Paul,

ABG = Arterial Blood Gas. You most definitely need arterial blood to get an ABG. You can maybe make some inferences from a venous blood sample if you jab it by mistake. However, it's not a great idea to do that with a critical patient.

You cannot measure SaO2 with a pulse oximeter. Pulse Oximeters measure SpO2 or the saturation of oxygen measured by pulse oximeter. Sp02 generally hovers within 1-2% of SaO2, but in cases where a patient has high carboxy-hemoglobin the SpO2 will include CO-Hb as well as O2-Hb. Always, always get an ABG (with Co-Oximetry if your facility requires a special order for that) if you suspect CO poisoning.

PaO2 is the measurement of the O2 that is 'free' in the plasma and not bound to Hb. PA02 is the pressure of alveolar O2 and is one of the measures used to assess a patient's oxygenation status.

If your patient had an SpO2 of 88% 3LPM via nasal canula would probably bring the patient's SpO2 up into the 90's.

I don't know if it's common for nurses to draw ABGs... I've never heard of a nurse drawing an ABG because they can't interpret them.

Next time a doctor yells for a PaO2 (depending on your hospital policy) make sure the doctor orders a stat ABG and call respiratory... unless your state allows nurses to draw, run, and interpret ABGs. In my state I would be scared if that were the case as I've met many nurses who confuse SpO2 with SaO2.

We draw ABG's all the time. We send them down to lab who processes it and posts the results just like any other blood work.

I work at a stand alone ER - we also manage the vents until we get bed placement at main campus. We are RT. We do not have that much ancillary staff.

Thank you!!

ACNP2017 said:

We draw ABG's all the time. We send them down to lab who processes it and posts the results just like any other blood work.

I work at a stand alone ER - we also manage the vents until we get bed placement at main campus. We are RT. We do not have that much ancillary staff.

They do not teach ABG's that in depth in most nursing schools, they say that if you go into Critical Care you will be trained based off of your facilities policy. ICU nurses and ER nurses may know how to draw ABG's but that doesn't mean they all know how to interpret them.

Many Med-Surg floor nurses do not draw ABG's, nor do school nurses, LTC nurses. So no the average nurse and especially a new grad nurse would not have the experience to interpret them unless they were trained on the job. Many facilites use RT for that. You are probably in the minority if you know how to interpret them.