Should we get a gas?

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migm

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Work at a large community hospital.

Elderly female last night with obvious LVO and on CTP a huge amount of MCA territory brain at risk (almost the entire hemisphere). GCS is 11 at best. She is going for EVT. I'm with her in scanner and she starts looking a little worse, some grunting respiration and increased respiratory effort. I decide to intubate for airway protection before she goes up to lab. RT comes in and says "Should we get a gas first?" and then scoffs when I say "no".

When I admit a COPD patient - "whats the gas show?"

Always an ABG mind you. I rarely if ever get ABGs where Itrained, intubation is a clinical decision and a gas will only rarely help (and even then a VBG is fine). Am i the outlier here?
 
VBG + pulse ox = ABG.

Intubation is a clinical decision. Yes an uptrending pCO2 can help you decide on that asthmatic that you're on the fence about, but I'm never waiting on a gas as my decision point.

Most of our RTs can't get an ABG half the time anyways.
 
No, you aren't. I never get ABGs unless they're already intubated and someone else (RT) will do it. VBGs are useful for showing a trend, but aren't the yes/no binary decision makers that internists and RTs love to coddle.
 
In 10 years, I can probably count on one hand the times I've used an abg as a surrogate intubation marker. 99% of the time in the ED, it's a clinical decision.

This is a case of you making a decision about intubation and allowing RT to sew doubts because they lacked confidence in the decision you made for the pt. You've been managing that pt from the time they arrived and RT probably showed up 2 mins ago. Don't second guess yourself. They are there to assist YOU, not to provide consultation.

Borderline equivocal DKA'ers, I will get a VBG. Occasional COPD'ers, I will get an ABG. A few house fires, CO2 poisoning, etc.. Otherwise, I don't really order that many in the ED. I think they are incredibly useful in the ICU but not really useful for us considering pt's normally are arriving in extremis leading up to intubation decisions and are not held in the ED for hours on end where abg plots would be incredibly useful. At most, a post intubation abg allowing FiO2 titration, etc... We just don't need them that often in the ED.
 
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Work at a large community hospital.

Elderly female last night with obvious LVO and on CTP a huge amount of MCA territory brain at risk (almost the entire hemisphere). GCS is 11 at best. She is going for EVT. I'm with her in scanner and she starts looking a little worse, some grunting respiration and increased respiratory effort. I decide to intubate for airway protection before she goes up to lab. RT comes in and says "Should we get a gas first?" and then scoffs when I say "no".

When I admit a COPD patient - "whats the gas show?"

Always an ABG mind you. I rarely if ever get ABGs where Itrained, intubation is a clinical decision and a gas will only rarely help (and even then a VBG is fine). Am i the outlier here?
Case 1: why the hell would you get a gas before tubing a stroke patient with AMS?

Case 2: If they're altered, yes, get a VBG. If they're not: "they aren't altered. There is no reason to get a VBG on this patient."
 
I get ABG on post tube, severe metabolic acidosis people and sometimes sick COPD/asthma.

Have had fair amount of arguments with dumb hospitalists about ABGs.
 
Work at a large community hospital.

Elderly female last night with obvious LVO and on CTP a huge amount of MCA territory brain at risk (almost the entire hemisphere). GCS is 11 at best. She is going for EVT. I'm with her in scanner and she starts looking a little worse, some grunting respiration and increased respiratory effort. I decide to intubate for airway protection before she goes up to lab. RT comes in and says "Should we get a gas first?" and then scoffs when I say "no".

When I admit a COPD patient - "whats the gas show?"

Always an ABG mind you. I rarely if ever get ABGs where Itrained, intubation is a clinical decision and a gas will only rarely help (and even then a VBG is fine). Am i the outlier here?

No you are not an outlier. One of the great things about emergency medicine is we are excellent at determining when people need to be tubed without relying on blood gases.

I occasionally get ABGs...maybe once/week, and it’s largely to placate the hospitalists. I’m just not gonna fight it. Once in a blue moon I’ll get an ABG in a COPDer who is on NIPPV and a little drowsy, but it’s not all that important. Occasionally i get a VGB/ABG if I suspect some whacked acid/base status, but then again...I just don’t really NEED it, it just makes admitting easier. Like someone who is breathing 28 times/min with a non-gap metabolic acidosis of 15. It’s unexplained after the initial workup, they clearly need to be admitted. I don’t need the ABG but it just makes admitting easier. Plus sometimes I’m interested in the outcome anyway. You could see 7.17/18 or 7.53/30...and the differential changes considerably with that knowledge.
 
Intubation is always a clinical decision. Keep in mind a lot of people who require intubation will have a normal gas because they don't necessarily have a respiratory issue requiring intubation. For example, the person in your case seems like is fairly altered due to an intracranial issue and had worsening mentation, requiring airway protection. If there is no respiratory issue, you won't even have an abnormal gas. This person would have likely had a normal gas.
 
For what it's worth, I do order VBGs once every 1-2 shifts, but generally for metabolic acidosis concerns.

The only time I'll send VBGs to help make an intubation decision is on people teetering on NIPPV for a couple hours waiting for a bed, especially the acute CHF patients. Multiple ICU docs have made the point to me that if the patient doesn't really look different but their gas is trending worse after 1-2 hours, they intubate, so I might as well do it if the patient is still waiting to go up.
 
Work at a large community hospital.

Elderly female last night with obvious LVO and on CTP a huge amount of MCA territory brain at risk (almost the entire hemisphere). GCS is 11 at best. She is going for EVT. I'm with her in scanner and she starts looking a little worse, some grunting respiration and increased respiratory effort. I decide to intubate for airway protection before she goes up to lab. RT comes in and says "Should we get a gas first?" and then scoffs when I say "no".

When I admit a COPD patient - "whats the gas show?"

Always an ABG mind you. I rarely if ever get ABGs where Itrained, intubation is a clinical decision and a gas will only rarely help (and even then a VBG is fine). Am i the outlier here?

Absolutely no reason to get a blood gas before intubation in the case you described. As you said: the intubation is for airway protection. A perfect gas would not stop your decision to intubate.

I do think ABGs are sometimes useful in COPD though. Immediately mostly for vent management. But in your regular run of the mill COPDer it can be useful for trending and when things change/don't change on morning rounds, it can be useful to compare the two. If suddenly all ABG machines disappeared, no one would die from their PaCO2 being unknown. But the same could be said for lots of tests we (ER docs) find useful too, like most POCUS indications.
 
Man, my new hospital loves ABGs. I agree, I hardly ever got any at my previous hospital and when I do, 99% of the time it is venous. Only time I'm really excited about an ABG is looking for methemoglobinemia, CO poisoning, can't get a good pulse ox reading.

If someone is breathing 50/minute, getting tired, but the gas is fine, you just gunna let that ride? Or your stroke patient gurgling secretions with a normal blood gas? Drives me nuts.
 
No man I agree. There is a role for ABG's in medicine and health care, but I can't think of any life-threatening situations in the ER where you HAVE to get an ABG right now prior to making a decision that will save someone's life. It doesn't exist.

That being said I do order them from time-to-time as I mentioned above, mostly to help facilitate flow.

Every now and then though, like on DKA'ers, I'm surprised at how good, or bad, their blood gas results are.
 
No man I agree. There is a role for ABG's in medicine and health care, but I can't think of any life-threatening situations in the ER where you HAVE to get an ABG right now prior to making a decision that will save someone's life. It doesn't exist.

That being said I do order them from time-to-time as I mentioned above, mostly to help facilitate flow.

Every now and then though, like on DKA'ers, I'm surprised at how good, or bad, their blood gas results are.

I find that on super sick COPDers it is sometimes very important to get a gas, even for initial vent settings. Sometimes when they are really bad I find I am balancing between giving them time to exhale to avoid breath stacking while accepting some permissive hypercapnia and a higher minute ventilation to blow off some of that CO2. Sometimes a gas makes a really good argument for one or the other. So I am not getting a gas to tell me whether I am going to intubate, but I am getting it before I intubate to help direct my ventilation strategy.

Could you just guess and/or just use the same approach for both patients? Maybe. But then some really sick people wouldn't do as well as they could. Maybe no one would even notice, because any deterioration can be blamed on them just be very sick, but that doesn't mean that resus optimization doesn't matter. If you practice in an environment where an ICU bed is very quickly available, then what you do maybe matters less, but not everyone practices in such an environment.
 
An ABG is very helpful for telling me who trained over a decade ago and hasn't bothered to keep up with medicine.

I graduated from residency less than 10 years ago and like to think I keep up with the resus literature at least. I used to have the same attitude as you roughly, and it's still partly true (out of all the times that an internist or a pulm/CC doc wants a blood gas in early resuscitation, only sometimes is it actually a good idea), but as with most things I find that the more you experience the more nuance you accept.
 
I find that on super sick COPDers it is sometimes very important to get a gas, even for initial vent settings. Sometimes when they are really bad I find I am balancing between giving them time to exhale to avoid breath stacking while accepting some permissive hypercapnia and a higher minute ventilation to blow off some of that CO2. Sometimes a gas makes a really good argument for one or the other. So I am not getting a gas to tell me whether I am going to intubate, but I am getting it before I intubate to help direct my ventilation strategy.

Could you just guess and/or just use the same approach for both patients? Maybe. But then some really sick people wouldn't do as well as they could. Maybe no one would even notice, because any deterioration can be blamed on them just be very sick, but that doesn't mean that resus optimization doesn't matter. If you practice in an environment where an ICU bed is very quickly available, then what you do maybe matters less, but not everyone practices in such an environment.

that's fine, and I agree I wrote earlier that I can see a reason to get an gas for COPDers on NIPPV, but these are not life-saving situations.

Depending on how good your vent is, some of that info you desire above can also be determined by looking at the fancy lines and graphs on the vent itself. Like how much air is moving during the exhale.
 
I think the lesson here is that RTs have their little patterns, and this one likes to scoff. And they don't make decisions about who gets intubated and who doesn't, and should stay in their lane, and let us make that call.

Just like the last sedation I did, the RT let out a little annoying chuckle during the time out, when I was looking for a cric kit. Because we "never need that" in this hospital (his words). Despite the fact that we did one 3 weeks prior - they don't know what their little minds don't know, and they have no idea what goes into a difficult airway case and the decision making. Sure, they read a book or saw some PowerPoints, but they haven't been in the thick of it, doing the procedures and putting your butt on the line.

People have their little patterns, and anything that deviates from that gets people in a tizzy.
 
To be fair, I’ve had hospitalists request a gas on COPD admissions not because it is particularly helpful clinically but because it can help them justify Inpatient vs Observation admissions.
 
I graduated from residency less than 10 years ago and like to think I keep up with the resus literature at least. I used to have the same attitude as you roughly, and it's still partly true (out of all the times that an internist or a pulm/CC doc wants a blood gas in early resuscitation, only sometimes is it actually a good idea), but as with most things I find that the more you experience the more nuance you accept.

Sure, I'm admittedly being a bit hyperbolic. Also, just to clarify, I'm commenting more on ABG vs VBG than on the utility of blood gasses in general.
 
I think the lesson here is that RTs have their little patterns, and this one likes to scoff. And they don't make decisions about who gets intubated and who doesn't, and should stay in their lane, and let us make that call.

Just like the last sedation I did, the RT let out a little annoying chuckle during the time out, when I was looking for a cric kit. Because we "never need that" in this hospital (his words). Despite the fact that we did one 3 weeks prior - they don't know what their little minds don't know, and they have no idea what goes into a difficult airway case and the decision making. Sure, they read a book or saw some PowerPoints, but they haven't been in the thick of it, doing the procedures and putting your butt on the line.

People have their little patterns, and anything that deviates from that gets people in a tizzy.

To add to that perhaps there is a component of being threatened. RTs sometimes don't get the respect/recognition they deserve for their knowledge and skill set, and sometimes that leads the more insecure among them to assert themselves in a bit of a maladaptive way. I also notice this among some EMS folks, NPs, and PAs. Always a small minority of all of the above, but it happens.

I find a lot of how that interaction goes with that kind of person depends on my tone. If I am dismissive in some way of their question of "should we get a gas?" or whatever, then a defensive scoffing happens more often. But if I non verbally communicate that I respect their input, thought about it for a second, and then decided no, then things go a lot more smoothly. Maybe it's obvious to some and maybe it sounds like I'm holding hands and singing kumbaya (I am not) but I've found it pays off bigly in the long term to pay attention to your non verbal cues and tone.
 
I used to be a VBG + pulsox = ABG guy before CCM fellowship. I get Abgs more, but not often.

Me too. (We are both EM-CCM, for folks who don't know this)

However, I think it would be beneficial for the forum:

When do you ask for an ABG? Does it ever make a difference to you? Does it ever effect your "walk-by" physical exam?

Outside of tox, when does an ABG benefit you more than an ABG?

Do you think the trend of pCO2 is valuable based on the first ABG (really, the difference between the pCO2 adn etCO2)?

HH
 
PGY-10 here.
I have never had an RT miss an ABG (I don't think).
I also never argue with them when they ask to get a gas.
 
When do you ask for an ABG?

I get them in several scenarios:
-first person to see the patient got an ABG; I want to trend so I get and ABG so I am comparing apples to apples
-pre-intubation for patients in shock
-pre-intubation for patients with severe COPD exacerbations in whom I think both acidosis/hypercapnia AND increased intrathoracic pressure are an issue, to help me plan my ventilation strategy
-post intubation for adjusting vent settings for most patients

Does it ever make a difference to you?
Most of the time not so much, but the sicker the patient is and the more abnormal their acid/base status is, the more I want an ABG. Post intubation I always want an ABG.

Does it ever effect your "walk-by" physical exam?
Not really, though sometimes when a blood gas is not really that off given the clinical picture, it makes me add different weight to the various issues going on in a patient. Sometimes that adds a little nuance.

Outside of tox, when does an ABG benefit you more than an ABG?
At extremes of physiology and post intubation.

Do you think the trend of pCO2 is valuable based on the first ABG (really, the difference between the pCO2 adn etCO2)?
Yes, because if I threw the kitchen sink at them and 1-2 hours later they look roughly the same clinically, it matters to me that their PCO2 went up from 80 to 120. It helps me figure out where they are headed. An etCO2 might not be as good of a tip off if they are not intubated (less accurate) and are moving less and less air (PCO2 might go up significantly while etCO2 not nearly so much if at all).

Vice versa, sometimes I get the patient that falls asleep after an hour on BiPAP and nebs, and its not because they are more hypercapneic but because they can finally rest a little. Sometimes it's clinically obvious, but sometimes an accurate PCO2 helps a lot with reaching that conclusion.
 
If you don't get an ABG, how do you know they're not faking respiratory distress?

<mic drop>
 
When do you ask for an ABG?

I get them in several scenarios:
-first person to see the patient got an ABG; I want to trend so I get and ABG so I am comparing apples to apples
-pre-intubation for patients in shock
-pre-intubation for patients with severe COPD exacerbations in whom I think both acidosis/hypercapnia AND increased intrathoracic pressure are an issue, to help me plan my ventilation strategy
-post intubation for adjusting vent settings for most patients

Does it ever make a difference to you?
Most of the time not so much, but the sicker the patient is and the more abnormal their acid/base status is, the more I want an ABG. Post intubation I always want an ABG.

Does it ever effect your "walk-by" physical exam?
Not really, though sometimes when a blood gas is not really that off given the clinical picture, it makes me add different weight to the various issues going on in a patient. Sometimes that adds a little nuance.

Outside of tox, when does an ABG benefit you more than an ABG?
At extremes of physiology and post intubation.

Do you think the trend of pCO2 is valuable based on the first ABG (really, the difference between the pCO2 adn etCO2)?
Yes, because if I threw the kitchen sink at them and 1-2 hours later they look roughly the same clinically, it matters to me that their PCO2 went up from 80 to 120. It helps me figure out where they are headed. An etCO2 might not be as good of a tip off if they are not intubated (less accurate) and are moving less and less air (PCO2 might go up significantly while etCO2 not nearly so much if at all).

Vice versa, sometimes I get the patient that falls asleep after an hour on BiPAP and nebs, and its not because they are more hypercapneic but because they can finally rest a little. Sometimes it's clinically obvious, but sometimes an accurate PCO2 helps a lot with reaching that conclusion.

What is this...a copy / paste from a FAQ?
 
Before intubating, the first thing you get from the patient should definitely NOT be an ABG. First get a Press Ganey. It should be absolute instinct.
 
First Press Gainey. Even better, give the patient a card and a self-addressed, stamped envelope where the patient can rate his ER experience after he is eventually discharged. You can make it easier and prefill out the card with "5 of 5 Stars for Dr. Birdstrike! It was a wonderful experience and he took good care of me."

Second, get consent if applicable.
 
I get an ABG in profound shock (likely deviates from VBG, certainly does in shock trauma) and can also inform if low SpO2 is from hypoperfusion, patients with chronic lung disease in whom we have previous ABGs, profound acidosis, patients with severe hypoxemia post-intubation to establish a baseline P:F (to determine trend as well as to decide to move towards probing/paralysis), pregnant women with respiratory failure, severe tachypnea, bad asthma, significant o2 requirement.

There’s likely a few others. I get an ABG maybe once a week in the ER, much more often upstairs.
 
Not a hill worth dying on for me.

I can either order the ABG and a RT gathers it for me or I order a VBG and have to listen to the hospitalist complain over the phone and request a follow up ABG prior to admission.

Personally, I order the ABG and go see the next patient. My time is worth more than this tiny academic problem.
 
Not a hill worth dying on for me.

I can either order the ABG and a RT gathers it for me or I order a VBG and have to listen to the hospitalist complain over the phone and request a follow up ABG prior to admission.

Personally, I order the ABG and go see the next patient. My time is worth more than this tiny academic problem.

I once had our IM director scream at me like an insolent child that I got a VBG instead of an ABG on a DKA patient I was admitting. I then emailed him the research paper saying it was "ok"


Never got an apology.
 
Not a hill worth dying on for me.

I can either order the ABG and a RT gathers it for me or I order a VBG and have to listen to the hospitalist complain over the phone and request a follow up ABG prior to admission.

Personally, I order the ABG and go see the next patient. My time is worth more than this tiny academic problem.
Except, there is more to it than this.
So if they ask, I simply tell them the patient refused. And then I go tell the patient that the other doctor wants a painful and unnecessary procedure on them, and that they should refuse it going forward.
Mess up their Press Ganeys, not mine.
 
I once had our IM director scream at me like an insolent child that I got a VBG instead of an ABG on a DKA patient I was admitting. I then emailed him the research paper saying it was "ok"


Never got an apology.

Don't you know better? The attending doing your evals is always right!

I once had a PICU attending who was critiquing my XR interpretation skills when I told her that a pt had a mild to moderate sized effusion (we read x-rays better than them anyway) and she made an example of me in front of the other residents. So, during morning rounds I grab an ultrasound machine and in front of the other residents show her the effusion that I had interpreted correctly on x-ray. I was all smug and proud of myself, mentally patting myself on the back. Her face turned blood red and daggers flashed in her eyes and only then did I have a bad feeling about what I had just done. Let's just say I didn't do myself any favors that day. She had a perma target on my back for the rest of that rotation.
 
Don't you know better? The attending doing your evals is always right!

I once had a PICU attending who was critiquing my XR interpretation skills when I told her that a pt had a mild to moderate sized effusion (we read x-rays better than them anyway) and she made an example of me in front of the other residents. So, during morning rounds I grab an ultrasound machine and in front of the other residents show her the effusion that I had interpreted correctly on x-ray. I was all smug and proud of myself, mentally patting myself on the back. Her face turned blood red and daggers flashed in her eyes and only then did I have a bad feeling about what I had just done. Let's just say I didn't do myself any favors that day. She had a perma target on my back for the rest of that rotation.

Worth it.
 
To be fair, I’ve had hospitalists request a gas on COPD admissions not because it is particularly helpful clinically but because it can help them justify Inpatient vs Observation admissions.

Funny, I always seem to get that request when trying to admit about 30 minutes before their shift change.
 
I get an ABG in profound shock (likely deviates from VBG, certainly does in shock trauma) and can also inform if low SpO2 is from hypoperfusion, patients with chronic lung disease in whom we have previous ABGs, profound acidosis, patients with severe hypoxemia post-intubation to establish a baseline P:F (to determine trend as well as to decide to move towards probing/paralysis), pregnant women with respiratory failure, severe tachypnea, bad asthma, significant o2 requirement.

There’s likely a few others. I get an ABG maybe once a week in the ER, much more often upstairs.

I’m on board with this approach and it reflects my practice. The referenced patient in the OP’s case can get their ABG from the arterial stick in the IR suite; there is no reason to delay things in the ED.
 
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