I have a question about the intubation I saw today...
Is it normal for neuromuscular blockers to be ordered before the sedative....??? I had drawn up etomidate and rocuronium... And I kept thinking to myself, he's probably going to ask for the etomidate first.... I have always heard that the patient should be sedated first because the feeling of becoming paralyzed is NOT NICE!!
I was really surprised when the doc asked for rocuronium first. I repeated everything back to the MD to make sure I heard everything correctly...
The patient did not look peaceful during this intubation!
I like this discussion. Okay so you have a CHF pt that's likely been getting worse over the past few days. RNexplorer: What could explain a ABG of respiratory alkalosis in this patient?
Or, if you can't figure it out, what are some causes of respiratory alkalosis in any patient?
If the patient is having lots of shortness of breath due to pulmonary edema (common in CHF), he/she may be tachypneic... Tachypnea, in turn, will cause too much CO2 to be expired, leading to respiratory alkalosis..
However, it's not this simple! Many CHF patients may also have other lung comorbidities and poor gas exchange, leading to respiratory acidosis...
Another possible reason for respiratory alkalosis could be anxiety and hyperventilation..
Basically, anything that causes tachypnea may (but not necessarily) cause resp alkalosis. You have to consider the whole patient and all of his/her comorbidities.
What I don't get is why this patient had respiratory alkalosis with sleep apnea... If the sleep apnea was really that bad, he would have had resp acidosis..
The indication given by the MD for intubation was sleep apnea, and I just don't understand why... In my mind, the sleep apnea could not have been that bad given his ABG... So why the heck was he intubated??????????
Right so respiratory acidosis would be caused by sleep apnea when the patient is asleep. But that's self limiting. When the patient awakes, they breath fine right? So ignore that that's what the MD said, it's likely they said that for medicare billing purposes or something like that. That's clearly not what's going on here.
This patient is hyperventilating due to one reason: Hypoxia.
So question, it was alluded to earlier that Bipap could be bad because it would potentially lower the CO2 more and really this patient needs something that will just decrease their stimulus to breath. Is this correct? What will happen if this patient tolerated Bipap and you placed them on it?
The patient was not actually hypoxic... his pO2 levels were actually elevated.
And I'm not too sure exactly how the patient would respond to the BiPAP... But I think it could lower the CO2 even more as others have already mentioned. Given that his pO2 levels were elevated, I'm not too sure how this treatment would be helpful.
Right so respiratory acidosis would be caused by sleep apnea when the patient is asleep. But that's self limiting. When the patient awakes, they breath fine right? So ignore that that's what the MD said, it's likely they said that for medicare billing purposes or something like that. That's clearly not what's going on here.
This patient is hyperventilating due to one reason: Hypoxia.
So question, it was alluded to earlier that Bipap could be bad because it would potentially lower the CO2 more and really this patient needs something that will just decrease their stimulus to breath. Is this correct? What will happen if this patient tolerated Bipap and you placed them on it?
If it takes a non-rebreather (with correspondingly high FiO2) to bring the patient's SpO2 up to 95%, something is wrong... and hypoxia is probably a big part of that problem. That something is probably brewing in the alveoli, capillary bed, or possibly in the bronchioles.
For the OP: Why would this patient not tolerate the BiPAP mask?
Throwing someone on a non-rebreather is generally going to make their pO2 levels tolerable for a while. It's more about the trending. My best guess (correct me if you think I'm wrong): Pt with CHF is hypoxic and starts hyperventilating subtly, right? So he puts it off for a day or two, then comes to the hospital because it's getting too bad. Abg shows compensated resp. alkalosis because the kidneys have started compensating for his respiratory induced alkalosis. Start him on a few liters nc and he's no longer hypoxic... for a bit. However, he then continues to get worse. He speeds up his breathing so that he gets enough O2 -> (metabolic alkalosis, pO2 may be normal d/t compensation with hyperventilation). Put him on a non-rebreather and yeah, his p02 levels will go up, but he may still be hyperventilating d/t the fluid in his lungs (lungs sense fluid and increase respirations regardless of p02 levels). This is why his 02 sat can be still be good, but the pt look like crap (or not look like crap but have a low pCO2 as in your case).
You'll see this all the time. This is classic CHF exacerbation. Put this patient on Bipap and it will fix them. Why? Because bipap uses positive pressure ventilation to force air into the alveoli, and concomitantly displace excess fluid from the lungs. The patient feels like they can breath again so they stop hyperventilating and their pCO2 actually comes back to normal. It seems counter-intuitive but it's how it works.
Since this patient can't tolerate the Bipap, intubation was the other choice (again, because he's not maintaining a normal c02, even though he is compensated.) It becomes a tough call about when specifically to intubate. This is where some people, even on this thread, say things like "be agressive" and others like to wait til you absolutely have to. Again, it's about trending everything that is going on with the pt and making a decision from that. This varies with doctor and facility policies.
Does this make sense? Does this match your clinical picture?
If it takes a non-rebreather (with correspondingly high FiO2) to bring the patient's SpO2 up to 95%, something is wrong... and hypoxia is probably a big part of that problem. That something is probably brewing in the alveoli, capillary bed, or possibly in the bronchioles.
For the OP: Why would this patient not tolerate the BiPAP mask?
In shift change at the start of my shift, I was told that the patient refused to wear the BiPAP because it was really uncomfortable... I'm not sure why he was okay with the non-rebreather....
I really think this patient's pulse oximetry must have been inaccurate... The paO2 was showing an elevated level, I think it was almost 120 mm Hg.. It was not a depressed value. As we are all aware, many things tend to lower the accuracy of pulse oximetry.
This is a huge mystery to me. The more we discuss it, the more muddled everything becomes. I don't think we are going to find an answer to all these questions on this forum b/c we don't have access to the actual lab data and clinical history and so on...
However, it's been fun chatting about this and I will definitely use this learning in future. Thanks to everyone's comments :)
In shift change at the start of my shift, I was told that the patient refused to wear the BiPAP because it was really uncomfortable... I'm not sure why he was okay with the non-rebreather....
I really think this patient's pulse oximetry must have been inaccurate... The paO2 was showing an elevated level, I think it was almost 120 mm Hg.. It was not a depressed value. As we are all aware, many things tend to lower the accuracy of pulse oximetry.
This is a huge mystery to me. The more we discuss it, the more muddled everything becomes. I don't think we are going to find an answer to all these questions on this forum b/c we don't have access to the actual lab data and clinical history and so on...
However, it's been fun chatting about this and I will definitely use this learning in future. Thanks to everyone's comments :)
A bipap is basically suctioned to a patients face vs a nonrebreather is gently placed on the face. Unfortunately lots of patients are noncompliant or refuse bipap because it is uncomfortable and tight on their face. They don't realize the non rebreather isn't going to help them the same and they could end up needing to be intubated which is far more uncomfortable than a bipap.
If the pao2 was 120mmHg it sounds like the patient was being over oxygenated and/or hyperventilating. You also said the patients abg showed respiratory alkalosis, its probably good they couldn't tolerate the bipap since it would further lower the co2.
I think you have gotten lots of decent advice to never be afraid to ask why. A good physician will never fault you for respectfully asking. I personally would never tell a doctor "I am giving the sedative first". He is the doctor I am doing what he orders if I do anything. I would be practicing outside my scope to tell a doctor that I am not giving the medication they ordered. How would that be different than me saying I am giving metoprolol not diltiazem or similar? I would however say "are you certain you want to give the paralytic before the sedative?" Or "here is xxxmg of Rocuronium doctor, I do not feel comfortable pushing it prior to the sedative".
In shift change at the start of my shift, I was told that the patient refused to wear the BiPAP because it was really uncomfortable... I'm not sure why he was okay with the non-rebreather....
I really think this patient's pulse oximetry must have been inaccurate... The paO2 was showing an elevated level, I think it was almost 120 mm Hg.. It was not a depressed value. As we are all aware, many things tend to lower the accuracy of pulse oximetry.
This is a huge mystery to me. The more we discuss it, the more muddled everything becomes. I don't think we are going to find an answer to all these questions on this forum b/c we don't have access to the actual lab data and clinical history and so on...
However, it's been fun chatting about this and I will definitely use this learning in future. Thanks to everyone's comments :)
A Pa02 of 120 on a non-rebreather is hypoxic. The patient would have to have a Pa02 in the 300s or 400s on a NRB to not be hypoxic.
A patient that needs a non-rebreather to have an SpO2 of 95% isn't actually doing all that well. That means the patient probably has an FiO2 of >90% to maintain that SpO2. If the patient is working to ventilate, that might not yet be reflected in the ABG quite yet. CPAP and Bi-Level depend upon the patient's own drive. If the patient becomes too tired, they're not going to be able to trigger the Bi-Level support all that well. That's why I was asking if the patient was tiring out. Tired patients just don't breathe all that well. When that happens, the patient then needs more emergent airway support with all the risks associated with having to organize and carry out an emergent intubation. I would hope that you wouldn't be calling for intubation based solely on ABG results.
95% On how many L of 02? It was never specified. 10-15L is a huge window to be maintaining 95% sp02. The patient could have been on 10L for all we know. Exhaustion plays a large role, but use of a BIPAP prior to intubation is crucial to any intubation protocol. VAP and trauma from intubation should be avoided if an easier intervention can be utilized. Every ICU nurse knows this and most docs will order a BIPAP before moving to intubation, unless emergent. I agree, seeing the ABGs would help.
95% On how many L of 02? It was never specified. 10-15L is a huge window to be maintaining 95% sp02. The patient could have been on 10L for all we know. Exhaustion plays a large role, but use of a BIPAP prior to intubation is crucial to any intubation protocol. VAP and trauma from intubation should be avoided if an easier intervention can be utilized. Every ICU nurse knows this and most docs will order a BIPAP before moving to intubation, unless emergent. I agree, seeing the ABGs would help.
Maintaining 95% on any flow > 2LPM by nasal cannula should signify that the patient isn't oxygenating properly for some reason. Most of us maintain that or greater on room air. Whether it's 10L or 15L still means the patient is getting an FiO2 well above RA, and well above what's possible/tolerable with a nasal cannula. If the patients PO2 was around 120, while that's quite good for a RA reading, it should be well over 300 when on a NRB mask.
Unfortunately for this patient, that mask wasn't tolerated and it's a very tight fit and probably can bring strong feelings of claustrophobia. If that happens... not good.
I think now that we've got at least some idea what was going on, and know that the patient wasn't tolerant of the BiPAP mask pretty much drives the need for intubation. Probably wasn't an emergent one, but most likely was one that still needed to be done soon.
Mully
3 Articles; 272 Posts
I like this discussion. Okay so you have a CHF pt that's likely been getting worse over the past few days. RNexplorer: What could explain a ABG of respiratory alkalosis in this patient?
Or, if you can't figure it out, what are some causes of respiratory alkalosis in any patient?