TXmed
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Has anybody implemented this into there protocol ? I've done it once to some success, but its not really in our protocols. It seems like its gonna be a new fad and just trying to gauge peoples experiences.
DSI, delayed sequence Intubation
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Critical Crazy
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This has been going around the FOAMed world for a couple of years now. I'm interested in seeing the results of the studies that are going on, but I think we are probably looking at a very small subset of patients that need something like this. In most cases you can knock someone down and mask them for a minute if needed before you intubate.
Brandon O
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Ketamine is not quite an inextricable element but pretty close to it. And not many folks are using ketamine in the field.
EMSComeLately
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Our drug assisted intubation uses Ketamine. And our violent patient chemical restraint also calls for Ketamine. I haven't had the occasion for either, yet.
Speedylifsavr
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I too am intrigued by this and wonder if there is only a certain subset of patients that will benefit from this. In a presentation by Dr.Scott Weingart (link below), He seems to feel this is a benefit to all patients who we may have considered using RSI. It seems like you are supersaturating the lungs with oxygen using 100%Fio2. Even going so far as to utilize peep keep the lungs inflated to enable the lungs to do their job (oxygen being diffused into the alveoli and Co2 leaving) even in the absence of mechanical ventilation. Does this sound right?
Is there a benefit to this even if the patient is completely apneic? Are pressure gradients enough to allow these gases (o2, Co2) to function properly at the alveolar level without ventilating the patient? it seems like you would get a buildup of Co2, but is this acceptable in light of the oxygen rich environment we are creating? So the end game is less time to desaturate while facilitating the advanced airway?
I think the video below increased my confusion in that he isnt actually ventilating the patient but using peep to keep the lungs inflated while introducing large anounts of o2 via NC and BVM but little to no compressing of the BVM. It also seems dangerous that if someone inexperienced were to utilize the method in the video and squeezed the BVM unecessarily it could cause barotrauma.
#confused
Is there a benefit to this even if the patient is completely apneic? Are pressure gradients enough to allow these gases (o2, Co2) to function properly at the alveolar level without ventilating the patient? it seems like you would get a buildup of Co2, but is this acceptable in light of the oxygen rich environment we are creating? So the end game is less time to desaturate while facilitating the advanced airway?
I think the video below increased my confusion in that he isnt actually ventilating the patient but using peep to keep the lungs inflated while introducing large anounts of o2 via NC and BVM but little to no compressing of the BVM. It also seems dangerous that if someone inexperienced were to utilize the method in the video and squeezed the BVM unecessarily it could cause barotrauma.
#confused
Brandon O
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Speedy,
You're referring to "apneic oxygenation," a concept Scott and some others have been championing for a while now. The basic principle (as you hinted at) is that if you can maintain a high concentration of oxygen in the pharynx and upper airways, it will indeed continue to flow into the alveoli on its own. This is because gas exchange in the alveoli is a passive process so long as adequate gradients are present, so whether or not you're breathing, you'll keep exchanging oxygen into the capillaries. Since you actually absorb oxygen faster than you replace it with CO2, you create a small amount of "suction" which keeps drawing down oxygen from the upper airways, and you can maintain a pretty high SpO2 for many minutes. They like to do this during intubation by putting on a nasal cannula at 15 LPM and leaving it there. Adding some PEEP only makes things better.
The issue is that while the gas properties help maintain a gradient of oxygen, the CO2 gradient is quickly abolished, so you oxygenate but don't ventilate particularly well, and over time you'll build up CO2. Not a huge problem over a matter of minutes, but obviously not a long-term solution.
The lecture above is about DSI, which is a different concept. That's for the spontaneously breathing patient who is having trouble and probably needs intubation, but is too agitated to tolerate good preoxygenation (via non-rebreather, CPAP, or whatever). You perform procedural sedation using an agent that spares the respiratory drive -- usually ketamine -- get them oxygenated and then proceed with intubation. It's not for a patient who is already apneic.
You're referring to "apneic oxygenation," a concept Scott and some others have been championing for a while now. The basic principle (as you hinted at) is that if you can maintain a high concentration of oxygen in the pharynx and upper airways, it will indeed continue to flow into the alveoli on its own. This is because gas exchange in the alveoli is a passive process so long as adequate gradients are present, so whether or not you're breathing, you'll keep exchanging oxygen into the capillaries. Since you actually absorb oxygen faster than you replace it with CO2, you create a small amount of "suction" which keeps drawing down oxygen from the upper airways, and you can maintain a pretty high SpO2 for many minutes. They like to do this during intubation by putting on a nasal cannula at 15 LPM and leaving it there. Adding some PEEP only makes things better.
The issue is that while the gas properties help maintain a gradient of oxygen, the CO2 gradient is quickly abolished, so you oxygenate but don't ventilate particularly well, and over time you'll build up CO2. Not a huge problem over a matter of minutes, but obviously not a long-term solution.
The lecture above is about DSI, which is a different concept. That's for the spontaneously breathing patient who is having trouble and probably needs intubation, but is too agitated to tolerate good preoxygenation (via non-rebreather, CPAP, or whatever). You perform procedural sedation using an agent that spares the respiratory drive -- usually ketamine -- get them oxygenated and then proceed with intubation. It's not for a patient who is already apneic.
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DSI really is a different concept and it can work for a certain subset of patients and it may prevent someone from needing intubation but it also allows you to proceed further down the intubation pathway. Think of it kind of like a slow RSI where you push your sedation agent, recheck the patient to see if they're improving/tolerating the CPAP or whatever you're using to provide oxygenation/ventilation assistance and if they're not, you proceed to intubate per usual RSI with apneic oxygenation to assist in extending the amount of time you have to get the tube in place as the patient may not desat during the intubation attempt.
Interesting concept but I don't know how useful it would be in the field because you just have to wait and see if there's improvement and you may not have the luxury of being able to do that. Then again, part of the concept may allow you to keep the patient on CPAP (or whatever) because the patient tolerates it because of the sedation...
Interesting concept but I don't know how useful it would be in the field because you just have to wait and see if there's improvement and you may not have the luxury of being able to do that. Then again, part of the concept may allow you to keep the patient on CPAP (or whatever) because the patient tolerates it because of the sedation...
CANMAN
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We do a very similiar procedure fairly often at my part-time Peds HEMS position with the goal of preventing intubation for critically ill asthmatics. Set them up on BiPAP and give them some Ketamine and it usually works well. Works really well for the younger patient's officially diagnosed with asthma, which you generally don't see classified as asthma until age 2 or greater.
OP
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TXmed
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I have done it a few more times since my post. It's great for providing pre-oxygenation on people who are combative from head injury or difficult to work with due to hypoxia
Bobbob1354
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I have been interested in the apneic oxygenation with the BVM, PEEP and NC combination. If you are not to release the EC grip on the pt in between ventilations, will CO2 build up in the lungs and dead air space, or does the PEEP valve still allow expiration of the CO2?
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The short answer is yes. When you're doing PPV with a PEEP valve, you're inflating the lungs with some pressure above what's set for PEEP. You do NOT remove the mask/break the seal because you do NOT want to lose the PEEP. Here's something to consider: if you inflate the lungs with the BVM w/ PEEP, once you stop squeezing the bag, do the lungs deflate? If the answer is yes, even if it's not entirely (due to PEEP) then CO2 will be exhaled...