Increased work of breathing on vent

[redy]

I have seen this not so infrequently.

What I see is pt is on PRVC (like every other patient) and is pulling in Tv of 600 to 700 when set at say 450 with peak pressures of 10 or so indicating that they are doing all the work. These are not necessarily patients with respiratory issues. For example the guy I have right now is intubated for airway protection. The solutions I see are

1. Knock him out, which I dont see the need for and can see being actually difficult at least to the level to get his TV down.

2. switch to VC but I usually see them still pulling excess TV

3. playing with Ti and peak flows and the TV usually haven't worked for me.

4. What I usually do is switch to pressure support which being flow cycled, I feel helps their work of breathing the best. However most attendings are uncomfortable with it and usually either disagree with me or just leave me to it.

I am just curious to see if I am wrong and if there are other solutions?

Thanks.

---

Members don't see this ad.

 

[sluggs]

You are absolutely correct!

 

[pulmoblast]

Generally if some has a high respiratory drive from non-pulmonary issues (like sepsis, acidosis, multi organ failure), no one ventilator mode is superior to the other IMHO, sedate and or paralyze are the best options, along w correction of the underlying cause ...all of these fancy vent parameters and acronyms are mental masturbation for a first year fellow or a over enthusiastic third year resident

 

[Hernandez]

The only caveat I'll add to the post above, is I prefer to maintain spontaneous drive if possible for usually quickly reversible conditions. The bad DKA who gets tubed with pH <6.9 and has an underlying drive to a minute ventilation 25+L/min let them help control acid base status while meds kick in, otherwise sedate them given the exceedingly high oxygen consumption their respiratory system can create

 

[redy]

Generally if some has a high respiratory drive from non-pulmonary issues (like sepsis, acidosis, multi organ failure), no one ventilator mode is superior to the other IMHO, sedate and or paralyze are the best options, along w correction of the underlying cause ...all of these fancy vent parameters and acronyms are mental masturbation for a first year fellow or a over enthusiastic third year resident

Agree. My scenario is more about the patient who has no obvious reason to pull those TV. No acidosis or sepsis. For example my patient has mulifocal CVA. Perhaps his huge TV are due to central issues. Nothing really I can do though other than make him comfortable on the vent.

Agree that if they have a reason and you still want to control then sedate or paralyze as needed.

Thanks for the replies.

 

[Hernandez]

If it's not adversely affecting their acid base status or oxygenation, let em ride, I often feel like a broken record quoting the SCCMs guidelines that vital signs should be used as a guide to look for something wrong and not as a titration goal for sedation.

 

[Mad Jack]

If they don't have ARDS or any other confounding pulmonary issues, why are you so hell bent on controlling their volumes to begin with? I feel like we often get more obsessed with the numbers than the big picture- are these volumes negatively impacting the patient and are they comfortable? Will they be on the ventilator long enough for such high volumes to negatively impact their pulmonary function? Are their peak pressures acceptable? If the big picture looks okay, why not let them ride on whatever settings don't leave them flopping around uncomfortably in the bed or completely knocked out and paralyzed?

 

[redy]

If they don't have ARDS or any other confounding pulmonary issues, why are you so hell bent on controlling their volumes to begin with? I feel like we often get more obsessed with the numbers than the big picture- are these volumes negatively impacting the patient and are they comfortable? Will they be on the ventilator long enough for such high volumes to negatively impact their pulmonary function? Are their peak pressures acceptable? If the big picture looks okay, why not let them ride on whatever settings don't leave them flopping around uncomfortably in the bed or completely knocked out and paralyzed?

I am not sure if its directed to me. I am not looking to control their TV, I am totally fine with whatever TV they are getting. The problem I am seeing is that they are working hard to get those volumes, as in they are doing all the work of breathing. I want the vent to help them. So I use pressure support due it being flow cycled. I feel that gives them their TV without them having to suck it in.

 

[Mad Jack]

I am not sure if its directed to me. I am not looking to control their TV, I am totally fine with whatever TV they are getting. The problem I am seeing is that they are working hard to get those volumes, as in they are doing all the work of breathing. I want the vent to help them. So I use pressure support due it being flow cycled. I feel that gives them their TV without them having to suck it in.

Ah, makes more sense. Do they look distressed? Generally I'm happy with a patient doing as much of their own WOB as possible so long as they aren't distressed and seem comfortable, makes for much less reconditioning and easier weaning. I'm just a med student/respiratory therapist though, so I could be missing something.