truetiger
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The facilities near us don't even bother sedating intubated patients....its almost criminal. They'll leave a fully alert and aware patient on assist/control.
What vent mode is best?
- Thread starter truetiger
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That depends on the disease process. For some over sedated and using a paralytic might sound "criminal".
Assist Control is also one of the most common and comfortable modes to be in if you are awake and definitely if you are on a transport ventilator. The ventilator will assist with every breath.
:unsure: That is news to me.
Many of the long term patients are on it in SubAcutes and home care.
ARDS patients and anybody admitted in distress will be placed on it.
It offers full support with a delivered preset VT.
A/C is the mode of choice for the majority of patients. SIMV gives too wide a variety of breaths and has been found to increase weaning time over a combo of A/C and CPAP+PS
Yes, A/C is the starting mode of choice although is it suited for awake patients? Pretty much every text I have, they list one of the disadvantages of A/C is patient ventilator dyssynchrony in awake patients.
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Yeah, I've transported a ton of long term trachs on A/C. Far more comfortable than being air hungry on SIMV.
Long term trach patients should not be on A/C. I know they place them on A/C but that is not correct. They should be on SIMV with Pressure support, they are air hungry on SIMV if you do not provide proper pressure support to them
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Ideally, yes. But it's definitely not mandatory by any means, especially at the more commonly used half-concentrations, and especially if you aren't on huge doses.
Even if you were on a larger dose, in the short time that most transports take, as long as you are careful to make sure the PIV doesn't get pulled on, neo, levi, or dopa should be perfectly fine through a PIV.
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OP
OP
truetiger
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How is a/c ideal for patients that are awake? If they're air hungry on SIMV then increase the back up rate. I can see it working for long term trach patients who are accustomed to mechanical ventilation, but not the medical pt who just got RSI'd.
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RocketMedic
Californian, Lost in Texas
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Weirdly, I generally agree with Clipper1.
Merck
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A/C Vol is certainly common but I'd say that for the awake pt with decent respiratory drive that PSV is generally better tolerated. Of course, people are adaptable and might settle nicely on different settings.
As for pressors, generally I'd only run dopamine peripherally or phenylephrine in a pinch. Anything else should go centrally. Sure you could half-strength some levo but why? Run it centrally or use an IO if need be.
As for pressors, generally I'd only run dopamine peripherally or phenylephrine in a pinch. Anything else should go centrally. Sure you could half-strength some levo but why? Run it centrally or use an IO if need be.
The key is "long term" trach patients. That means they are ventilator dependent and not weaning.
You need to look at the wave form graphs and check out the flows. SIMV is a weaning mode and not used very often for that either. Unfortunately it seems the text books you might be referencing might be about 30 years out of date.
Why would you be placing a CCT patient on PSV? You should not be screwing around thinking you can get the patient extubated before the next hospital.
Why would you use a weaning mode on a patient who just got RSI'd. Their confusion waking up with the variation in flows would be detrimental to their ventilator synchrony. How would you even determine the idea PSV setting on a paralyzed patient when they wake up?
VFlutter
Flight Nurse
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Clipper,
The button directly to the right of the "Quote" button is the multi-quote button. You can click that on as many posts as you want and then click the "Quote" button allowing you to reply to all in a single post. It is much cleaner and easier to follow.
Just FYI
The button directly to the right of the "Quote" button is the multi-quote button. You can click that on as many posts as you want and then click the "Quote" button allowing you to reply to all in a single post. It is much cleaner and easier to follow.
Just FYI
Thanks. I tried that a couple of times and lost all I had written. But, I'll try it again if needed.
A true Assist Control mode is not synchronized with the patient breathing. Thus breath stacking and patient ventilator dyssynchrony will occur if the patient is not sedated and is fully awake. Place ETCO2 on awake patient on assist control mode and see the numbers go down due to that.
RSI patient can go on A/C no problem, you stated awake patients should be on A/C, and I disagree.
SIMV is not only used for weaning trials.
Essentials of Mechanical Ventilation, Second Edition [Hardcover]
Dean Hess (Author), Robert Kacmarek (Author)
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Modern ventilators are designed to with sensitivity levels to be set. If your patients are out of synch in an AC mode, you need to adjust the sensitivity and check the termination flow setting.
AC in both the volume and pressure modes is the most common since it does as its name states "assist".
ETCO2 numbers going down can be a good thing. It means the patient is ventilating which is the purpose of a ventilator. Being out of synch would cause the numbers to increase with air trapping. I will state again to use the graphs. If the patient is breathing too fast, you need to assess pain levels and the meds you are using for a critically ill patient before you blame the technology.
We run ETCO2 on most of our ventilator patients in the ICU and EDs so I do have an idea about vent modes and their relationship with ventilation and oxygenation.
I see no purpose in putting a patient in SIMV with one breath at 500 and another at maybe 100 or 200 ml especially when acutely ill and variations in compliance. No patient with a plateau pressure above 30 should ever have to struggle to take a breath on PSV. But, how are you going to determine plateau pressure on most transport ventilators?
EDIT:
Your last post made our points concerning the difference between the modes a little clearer. If a patient has decreasing it would be more beneficial to have a set VT given which would also give a better indication that a different mode of higher ventilation is needed. If you are transport without a graphic monitor, you can at least tell by the PIPs that your patient needs attention. If in SIMV with PSV you may not realize that the VTs in PS are next to nothing and the patient is struggling for their spontaneous breaths. In AC, that is not a problem. If the patient is asynch, check your patient, meds and the settings.
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Sensitivity is not the issue here: in A/C you can provide assisted breath however they are not in synch to patient own respiratory effort. That means if awake patients triggers A/C for an extra breath and ventilator provides it and the next scheduled A/C breath falls right after it timing wise the patient will get breath stacked. SIMV accounts for that and adjusts the timing hence more preferred for awake patients. SIMV does not just mean weaning trial mode.
Hence why S in SIMV stands for synchronized. There is no synchrony in A/C.