How do you do SBT's

[VentdependenT]

Cpap 5? Why not cpap 6? Why do RTs freak out when they see this? "Oooohhhhh hes sucking through a straw! You try that doc!"

Pressure support 8/5? Why not 10/5? Why not 5/5? Why not just push the old "tube comp" button?

Tpiece? How can you check a rsbi?

Do the specifics matter or is it the aaplication of continual assesment of readyness to achieve liberation from mechanical ventilation that counts?

"Oohhhh the pt is on pressors, must wait till they are off even though pt looks better"

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[Hernandez]

Cpap 5? Why not cpap 6? Why do RTs freak out when they see this? "Oooohhhhh hes sucking through a straw! You try that doc!"

Pressure support 8/5? Why not 10/5? Why not 5/5? Why not just push the old "tube comp" button?

Tpiece? How can you check a rsbi?

Do the specifics matter or is it the aaplication of continual assesment of readyness to achieve liberation from mechanical ventilation that counts?

"Oohhhh the pt is on pressors, must wait till they are off even though pt looks better"

Where I trained, we weaned to 5/5, where I am at, the other pulm docs have them 8/5.

I have the philosophy, unless you're actively dying and you're on a FIO2 of less than 70%, including the pt my goof ball co-fellow put on 67%, you CPAP every day. I dont care if its only for 5 minutes, but I Want to see what you do.

I can't tell you how much crap I've gotten from RTs who pull the "he's sucking through a straw" or "unstable" or "we don't CPAP with a peep above 5cm" or "have you heard of PAV?"

there are a hundred ways to wean a pt, and ultimately as a pulmonologist, you should be able to look at 90% of pts and know if they're ready or not. The other 10% is part educated guess and part good ole college try.

Personally, I only t-piece people I think will go back into pulm edema from lose of peep as using t-piece costs money in supplies to hook them up, and can be more uncomfortable, I also don't wait more than 20-25 minutes to decide to yank to tube. I do poor mans RSI on t-piece, have them force exhale and if I can feel it on my glove, they're getting good TV

If they're kinda marginal, or I'm using higher peep or PSV but I really want that tube out, I will extubate to bipap. Especially fatties (who weren't super difficult tubes)

There is some minor "physiologic" rhyme and reason to the numbers people pick(OMG! Normal trans pleural pressure gradient is 5cm! That's what PSV should be when you extubate to simulate physiologic conditions!) 🙄, really, most of it is basically voodoo and preference.

Really....lets talk about the RSBI......all it says is the same thing you already now, low RR in people taking regular sized breaths likely aren't going to fail being extubation. STANDING OVATION FOR that masterful conclusion.....

sorry, I'm a extubation tyrant and I,m sure my reintubation rate is higher than most, but i believe you should be ashamed if you're re-intubation rate is less than 5%, where did I come up with that number? I pulled it out of my ass, like most of these numbers are.

.....😀

 

[Hernandez]

"Oohhhh the pt is on pressors, must wait till they are off even though pt looks better"

Wanna screw with a MICU RT? Tell them its the vent causing hypotension from being intravascularly dry from following the FACCT trial, so we must extubate him to make him better...or make him do a PEEP trial of 0 to see if it helps they're BP,

 

[sluggs]

I am never more generous than 5/5. Tobin wrote an editorial in the Blue Journal about 16 months ago advocating for T-piece, and made a number of good points, including that the post-intubation-extubation airway ain't pretty, and there is no "tube compensation" once the tube is out.

 

[Bostonredsox]

5/5 all day, check rsbi and vitals.

extubate. sink or swim.

for bad copdr's who are damn near bipap dependent, I put them on bipap 14/8 through the vent for 90 minutes or so. check parameters. if they fly, I extubate them to bipap 14/8 and wean from there.

no hard data, just what I like to do. We don't t-piece here. I also don't do a whole lot of 'lets put them on simv/psv for a day to get them working then try and extubate tomo". my literature review coupled with patients I have tried it on tells me it does not liberate them any faster. So unless they have been on AC for like 10 days- 2 weeks, I go from AC right to SBTs.

 

[jdh71]

t-piece would be the best way but it's too resource intensive to be practical with most patients. I ask for t-piece trials on bad hearts

otherwise I've seen 8/5, 7/5, 5/5, 0/5. everyone's pretty dogmatic about it. whatever, it all seems to work. I think the bottom line is that extubation fails ~10% of the time, so if you're numbers aren't running around in there you are either extubating too soon or not soon enough.

now to what I do? I just loosen the restraints enough so that they can slip their hand up to the ET tube, if they can get it together enough to yank the tube, I can really appreciate that tenacity, just like letting baby sharks out of the eggs to kill or be killed. survive or die. it's the law of the jungle. heh.

 

[Hernandez]

I am never more generous than 5/5.

There are days I channel my inner PACU anesthiologist, push fentanyl, Ativan, PSV of 12 and pull the tube

 

[bigtuna]

We use PS 8 on ETT size 7 or smaller and PS 5 on everything else.

After the tobin editorial (I agree lots of good points) we started doing a 30 minute trial of PS/Peep 0 prior to extubation on almost everyone - don't use it on those that are a slam dunk to fly.

I think the 0/0 may be overkill in most but good idea in those with bad underlying cardiopulmonary disease.

 

[VentdependenT]

We use PS 8 on ETT size 7 or smaller and PS 5 on everything else.

After the tobin editorial (I agree lots of good points) we started doing a 30 minute trial of PS/Peep 0 prior to extubation on almost everyone - don't use it on those that are a slam dunk to fly.

I think the 0/0 may be overkill in most but good idea in those with bad underlying cardiopulmonary disease.

Maybe im having a TIA but really what is the puropse of CPAP for 30 min on a vent? Does it really do anything? Reallllyyy?

 

[bigtuna]

Let me clarify. We start the SBT with PS/PEEP of 5. If the pt tolerates that, we decrease the PS/PEEP to 0 (flow-by mode on the vent). If they do ok with that, then we extubate.

I was actually against the change when we first started but I've been surprised by the number of people that can tolerate PS/PEEP 5 fine and then don't tolerate 0/0.

You can make the argument that this approach may end up delaying extubation in too many people but I think it has cut down reintubation rate in a group of patients that are more susceptible to adverse events associated with reintubation because of limited cardiopulmonary reserve. I'm talking about the patients with EF of 10%, or FEV 1 of 0.8L, or baseline pCO2 50's.

 

[Hernandez]

Maybe im having a TIA but really what is the puropse of CPAP for 30 min on a vent? Does it really do anything? Reallllyyy?

If a pt isn't actively dying, I make them CPAP everyday, I don't care if its only 5 minutes, or all day, my reasoning (and I'll admit not well supported, but show me any of this voodoo that is) I have it done while I'm around so I can see what they do, it gives me a better barometer on when I think I can extubate them. I like to think that giving them better control of their MV is more comfortable, I also like to justify to myself that perhaps PSV has less diagphrmatic atrophy ala BiLevel. More importantly, I just like the RTs to get in the thought process that they have to have a reason NOT to try and wean a pt.

 

[Hernandez]

Let me clarify. We start the SBT with PS/PEEP of 5. If the pt tolerates that, we decrease the PS/PEEP to 0 (flow-by mode on the vent). If they do ok with that, then we extubate.

I was actually against the change when we first started but I've been surprised by the number of people that can tolerate PS/PEEP 5 fine and then don't tolerate 0/0.

You can make the argument that this approach may end up delaying extubation in too many people but I think it has cut down reintubation rate in a group of patients that are more susceptible to adverse events associated with reintubation because of limited cardiopulmonary reserve. I'm talking about the patients with EF of 10%, or FEV 1 of 0.8L, or baseline pCO2 50's.

If I were in your institution, I'd have the managers pull the vent day & re-intubation rate data pre-post this change just to see. I'm not saying you're wrong, I can understand the justification I just don't mind being more agressive with extubations in people who weren't a difficult airway the first time. Yes, I'm aware that re-intubations can be harder, but VAPs kill too.

 

[europeman]

Bigtuna,

You start SBT with peep 5 and PS 5? and then down to peep 5 with no pressure support? clarify kindly!

 

[bigtuna]

Bigtuna,

You start SBT with peep 5 and PS 5? and then down to peep 5 with no pressure support? clarify kindly!

Start with PEEP and PS both 5 then drop to PEEP and PS both 0.


I think >90% of the extubation failures i see are due to post extubation stridor or inability to clear secretions.

 

[Hernandez]

I think >90% of the extubation failures i see are due to post extubation stridor.

How many of these do you see a year?

 

[VentdependenT]

So, the CPAP of 5 is to mimic intrinsic peep?

Good discussion yall.

 

[VentdependenT]

How many of these do you see a year?

just got one s/p TAA repair: left recurrent laryngeal nerve toast. trach town

 

[bigtuna]

How many of these do you see a year?

Couple a month maybe. High volume practice.

 

[Bostonredsox]

Start with PEEP and PS both 5 then drop to PEEP and PS both 0.


I think >90% of the extubation failures i see are due to post extubation stridor or inability to clear secretions.

I would be interested to know if their is a failure rate difference comparing 5/5->extubate with 5/5->0/0->extubate. If their isn't, its just additional time breathing through a straw without some pressure support.

To the notin on some patients tolerating 5/5 but not 0/0, it sounds like these are the patients that I would extubate from 5/5 to bipap. Slowly wean the support from there.

 

[Hernandez]

So, the CPAP of 5 is to mimic intrinsic peep?.

In theory.

 

[Hernandez]

Couple a month maybe. High volume practice.

Must be, I think I have only seen a handful each year. You do more CC than pulm? (I seem to remember you're pulm-CC attending, right?)

 

[bigtuna]

Must be, I think I have only seen a handful each year. You do more CC than pulm? (I seem to remember you're pulm-CC attending, right?)

Yeah - about 75% cc, 25% pulm. There's a few in my practice that have been doing CC for over 20 yrs and they've really bought in to this 0/0 theory.

 

[dbiddy808]

At my hospital the RTs love ASV. It pre-dated my being there. Where I did fellowship it was AC and PSV. I find looking at the pressure support numbers on ASV are misleading as they target higher tidal volumes than I would target with PSV.

Having said that...I first I assess their level of sedation. Next, I see if they are breathing spontaneously or riding the vent. If they are not breathing spontaneously I drop their minute ventilation in half to allow CO2 build-up. Usually they start breathing within a few minutes. Once I establish they are triggering I switch to 5/5 and get an idea of their compliance. If they look good I have the nurse turn off the sedation and wait for them to wake up. If they look good, I pull call RT and ask them to pull the tube. If it is borderline I have the RTs do a formal SBT. The problem with formal SBTs is that people become anxious and often become tachypnic and tachycardic. If that is the case, I usually switch to precedex and give them another day on the vent and try again the next day.

Not evidence-based...but it seems to work.

 

[Bostonredsox]

At my hospital the RTs love ASV. It pre-dated my being there. Where I did fellowship it was AC and PSV. I find looking at the pressure support numbers on ASV are misleading as they target higher tidal volumes than I would target with PSV.

Having said that...I first I assess their level of sedation. Next, I see if they are breathing spontaneously or riding the vent. If they are not breathing spontaneously I drop their minute ventilation in half to allow CO2 build-up. Usually they start breathing within a few minutes. Once I establish they are triggering I switch to 5/5 and get an idea of their compliance. If they look good I have the nurse turn off the sedation and wait for them to wake up. If they look good, I pull call RT and ask them to pull the tube. If it is borderline I have the RTs do a formal SBT. The problem with formal SBTs is that people become anxious and often become tachypnic and tachycardic. If that is the case, I usually switch to precedex and give them another day on the vent and try again the next day.

Not evidence-based...but it seems to work.

I think your last sentence somes it up. Most of what we all do is based on our own clinical trial and error and the system we have found that works best in our minds. Not a lot of bonafide randomized control data on the success rates in comparison of different methods that I have come across. Please link some if you have them.