The death of the PAC

[anes]

How about the Flotrac and other monitors using the arterial waveform? These monitors are quite useful for C.O. and correlate well with TEE.
I have no experience with the Nexfin myself except a demo by the rep on an ASA1 person. On the other hand, the monitors which utilize the arterial waveform to obtain C.O. seem to be quite useful in Cardiac patients especially for trending of C.O.

Flotrac and vigileo at amazing. As long as tidal volumes are kept 8/kg and the patient has regular rhythm it seems accurate. SVV for fluid resuscitation is probably the best monitor (if no echo is available) . CO/CI are very accurate in regular rhythm as well. However in our experience we've found that in patients with A. fib you can get somehwat reasonable cardiac output if you change the data interval from the default (10 seconds I believe) to 2 minutes. The obvious downside is that you will be behind 2 minutes on their true cardiac output state.

The flotrac is pretty useless it seems in non-intubated non-ventilated patients. That doesn't stop some surgeons from using it for management in our icus though.

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[deleted171991]

The flotrac is pretty useless it seems in non-intubated non-ventilated patients. That doesn't stop some surgeons from using it for management in our icus though.

The former makes perfect sense, since Flotrac relies on the analysis of the arterial pressure waveform, which is unreliable with spontaneous ventilation.

 

[DreamLover]

Just imagine the patients' PTSD. Not because of you, but most patients are hyperalgic in the ICU and remember vividly their painful experiences.

I felt awful for those patients...that's where a lot of the anxiety came from. I don't miss that at all.

 

[deleted171991]

The problem with the ICU lines is that the kits don't have enough lidocaine, and residents are not taught how to topicalize properly.

 

[DreamLover]

The problem with the ICU lines is that the kits don't have enough lidocaine, and residents are not taught how to topicalize properly.

I'd always grab a second vial to have enough to localize the suture site...that curved pop off from the kits we used was not a small needle at all

 

[fakin' the funk]

I wouldn't go that far. ANYTHING is fair game in the oral boards. And they find a way to ask about every major subspecialty, including cardiac and ICU. Besides, even Marik admitted that the PAC has some use in specific situations (pulm HTN, RV failure, etc).

We talked about pulse pressure variation as well as PA cath numbers on my oral boards. Yes everything is fair game.

That said, Marik is an intensivist so I don't think a lot of examiners give a $hit what he thinks.

 

[deleted171991]

As long as you can defend your choice, anything reasonable goes.

"I wouldn't use the PAC because, in this case, the benefits don't justify the risks. I would rather use TEE instead."

Now that might start an entire discussion about the risks of the PAC, what you can measure with the PAC, the risks of TEE, how you do the TEE, and what you would see on it exactly etc. But that's something you should know anyway.

 

[geogil]

Here we have PPV as an option on the Phillips monitor, sadly most people don't know the preconditions that must be met for it to be valid. Frequenly I have folks telling me "the PPV is 10, i'm giving more fluid", in a patient being ventilated at 6ml/kg, in afib.

 

[BobBarker]

Agreed. I would never place a PA cath on my oral board scenario because I know that isn't a strong point for me. I only placed 3 as a resident. All on liver transplants.

 

[sevoflurane]

Agreed. I would never place a PA cath on my oral board scenario because I know that isn't a strong point for me. I only placed 3 as a resident. All on liver transplants.

Wow. Has the use of PAC fallen that much out of favor in academics?

 

[fakin' the funk]

Wow. Has the use of PAC fallen that much out of favor in academics?

We place(d) them on every cardiac surgery case where I did residency. So I placed ~50.

 

[epidural man]

I love the CardioQ.

What a brilliant idea - measure the volume and speed that the blood is leaving the heart - and the device is easy to place.

 

[sevoflurane]

I love the CardioQ.

What a brilliant idea - measure the volume and speed that the blood is leaving the heart - and the device is easy to place.

It's pertty good if you can align the flow with the doppler. I find that it can be hard to get good alignment on some patients. My N is only about 25-30 patients. Maybe the technology has evolved, but the device I used is the exact one pictured below. I forget how expensive the probes were, but they are not reusable (at least the ones I used)... although you can keep them in well into their ICU stay.

 

[epidural man]

It's pertty good if you can align the flow with the doppler. I find that it can be hard to get good alignment on some patients. My N is only about 25-30 patients. Maybe the technology has evolved, but the device I used is the exact one pictured below. I forget how expensive the probes were, but they are not reusable (at least the ones I used)... although you can keep them in well into their ICU stay.

Agreed the device can be finicky. Just like a pulse ox probe, or an a-line, or an EKG lead can.

They are way to expensive - this is true. I wonder about the non-reusable thing. It is made of durable plastic that can be cleaned. Not allowing it to be reusable is a company driven policy I am sure. I have wanted to do a study or two with the device and think I would reuse the probe - but haven't pursued it beyond a pipe-dream.

As a resident, I did a study using cerebral oximetry and reused those probes - just cleaned them each time. It worked great. The company also says you absolutely can't reuse those.

 

[napman]

Hi all I will be a devils advocate for PAC in my next 2 posts
when you say ECHO is superior to PAC . I want to know how you evaluate the following parameters using ECHO
Preload: what are you using to find if preload is optimal
Are you using LVED area or volume or just eye ball? LVEDV is a static pre load indicator and is not the best preload indicator. Are you doing LVOT VTI variation, which is extremly difficult to obtain
Contractility: Are you mesuring dt/dp? or are you mesuring EF by just eye balling which is dependent a lot on loading condition

Cardiac output: Are you mesuring the VTI across LVOT to determine cardiac ourput in all your patients, which is prone to lot of errors based on how you mesure LVOT diameter and angle at which your CW doppler evaluates VTI, and it is not a continous mesurement

After load: How do you say what after load

If eyball assesment is the only thing you do with ECHO , it becomes very subjective and equelly unreliable as PAC.

ECHO like PAC has its own downsides and compliments the data from PAC

 

[napman]

Now about PAC
SVo2 : A low Svo2 always indicates inadequate 02 delivary. normal Svo2 in most of clinical scenarios indicates adequate o2 delivery
CCO : it indicates cardiac out put few minutes back ( there is a significant time lag ) but can be used to see the response to your intervention, eg. give fluid bolus or straight leg raise test and see if patient is fluid responsive vs non responsive. Give inotropes and see if CO improves. There is no gold standard for cardiac output mesurement but Bolus cardiac out put moniter is still a standard for cardiac output measurement and can be used to see if CCO ( continous) is reliable
CVP and PAOP: are not good as preload indicators and use should be prohibited
PA pressures: elevated PA pressures with low PAOP will help identify protamine reaction

Monitors do not change mortality it is the person who uses them and how they use them that makes the difference. NIBP measurement and Spo2 measurement have never shown to improve mortality.

As far as invasiveness is concerned if you are puting a central line for a heart case floating a PA catheter dose not significantly increase mortality

 

[Mman]

Preload: what are you using to find if preload is optimal
Are you using LVED area or volume or just eye ball? LVEDV is a static pre load indicator and is not the best preload indicator. Are you doing LVOT VTI variation, which is extremly difficult to obtain

LVEDV by eyeball. It's easily a far better measurement than anything off a PA cath. Is the LV filled or are the walls kissing? Pretty obvious if you ask me.

You state LVEDV is "not the best preload indicator". I agree. LVEDP is the best preload indicator and we currently have no way to measure it routinely. LVEDV is literally the next best thing.


PA caths are terrible.

 

[Mman]

Monitors do not change mortality it is the person who uses them and how they use them that makes the difference. NIBP measurement and Spo2 measurement have never shown to improve mortality.

Spo2 measurement has been shown to decrease mortality. It's just not from a randomized trial. It's the global decrease in anesthetic mortality before and after it became routine.

 

[napman]

LVEDV by eyeball. It's easily a far better measurement than anything off a PA cath. Is the LV filled or are the walls kissing? Pretty obvious if you ask me.

You state LVEDV is "not the best preload indicator". I agree. LVEDP is the best preload indicator and we currently have no way to measure it routinely. LVEDV is literally the next best thing.


PA caths are terrible.

There are lot of filling volumes between LV filled vs walls kissing

LVEDV is better preload indicator than LVEDP
PAOP is an indirect estimate of LVEDP
the problem with LVEDV as a preload indicator is it is a static preload indicator like CVP and PAOP vs dynamic preload indicators like SVV (stroak volume variation) or PPV

 

[napman]

Spo2 measurement has been shown to decrease mortality. It's just not from a randomized trial. It's the global decrease in anesthetic mortality before and after it became routine.

Agre with you 100% , but let me put it in a different way
What if some one relies on spo2 and does not diagnose hypoventilation is it the problem with monitor or the person interperating the monitor

 

[Stank811]

No one has answered my question….if you do not use a PAC what do you use to titrate inotropes both intra-op and post op.

 

[Mman]

LVEDV is better preload indicator than LVEDP

Not really. I mean the "volume" is the preload, but the wall tension against the LV is what drives the frank-starling curve. That is determined by several things including the "stiffness" of the ventricle, but the trend in how that LVEDP changes is ultimately what you want to know. A ventricle that has a full volume can still not have maximized the efficiency of the EF of the LV.

 

[Mman]

No one has answered my question….if you do not use a PAC what do you use to titrate inotropes both intra-op and post op.

Noninvasive CO? Lactate? pH? BP? Urine output?

There are lots of things that you can use to help guide inotrope therapy. I mean we use all sorts of inotropes on non cardiac patients without a PA cath.

 

[napman]

Not really. I mean the "volume" is the preload, but the wall tension against the LV is what drives the frank-starling curve. That is determined by several things including the "stiffness" of the ventricle, but the trend in how that LVEDP changes is ultimately what you want to know. A ventricle that has a full volume can still not have maximized the efficiency of the EF of the LV.

The basis for definition of preload is laplace law
for thick walled structure like ventricle, wall stress (preload)= P x R/2W, P is pressure, R is radius and W is wall thickness
so preload = LVEDP xLVEDV/2 Wall thickness. so both LVEDV and LVEDP are both components of preload.

for a given LVEDV a patient with failing heart may be at platue phase of Starlings curve vs a patient with healthy heart may be in steep part fo starlings curve. So one value of LVEDV or P may represent different states of ventricular stress base on patient

 

[Mman]

The LVEDP is the load stress on the wall of the ventricle and is what determines where on the frank-starling curve you are. It is not an actual number that matters, but a trend for that particular ventricle.


The morale of the story is always that PA caths provide very little benefit to a patient and do add risk.

 

[napman]

The morale of the story is always that PA caths provide very little benefit to a patient and do add risk.[/QUOTE]

So dose the TEE

 

[sevoflurane]

So dose the TEE

What's the inccidence of esophageal perforation with TEE?

 

[sevoflurane]

http://portal.mah.harvard.edu/templ...documents/Min JASE 2005 TEE Complications.pdf

10,000 patients. Zero fatalities.

 

[sevoflurane]

How often does TEE guide therapy or change the surgical outcome based on intraoperative findings?

How many TEE cardioversions are done per day in the USA?

TEE is safe. It provides a wealth of information.
Remember TEE is superior to TTE in more ways than one.

 

[sevoflurane]

 

[sevoflurane]

Finding the above in the arch or thoracic aorta has serious consequences and surgical technique must be changed if found. At the very least, it should prompt an epiaortic scan. Benefit far outweighs risks.

 

[napman]

I am not debating about utility of TEE as a diagnostic mode, I am saying that TEE has same inadequacys as PA catheter in guiding hemodynamic managements. As far as complications of PA catheters are concerned the incidence of serious complications with PA catheters is 0.016% and only 1 in 2000 of these compications is directly related to PA catheter and most of them to accesing venous system. So if you are already puting in a central line the added complication involved with floating a PA catheter and not wedging ( I do not wedg) it is very minimal. Most of the complications involved are mainly because of lack of knowlage to inteprete the results which can happen with both the monitors.
As far as I am concerned, PA catheter still has place in hemodynamic managment if you know how to use it

 

[nimbus]

I am not debating about utility of TEE as a diagnostic mode, I am saying that TEE has same inadequacys as PA catheter in guiding hemodynamic managements. As far as complications of PA catheters are concerned the incidence of serious complications with PA catheters is 0.016% and only 1 in 2000 of these compications is directly related to PA catheter and most of them to accesing venous system. So if you are already puting in a central line the added complication involved with floating a PA catheter and not wedging ( I do not wedg) it is very minimal. Most of the complications involved are mainly because of lack of knowlage to inteprete the results which can happen with both the monitors.
As far as I am concerned, PA catheter still has place in hemodynamic managment if you know how to use it

Agree risk of pa catheter is minuscule, especially with US and TEE guided insertion which is the only way I do it these days.

I also never wedge.

 

[OB1🤙]

I agree that the insertion risk for someone who knows what they're doing is very small. I also don't wedge.

I think the risk is not in the OR. Rather, it's that others may mismanage the patient afterward. This is what I see most commonly. Inotropes for a borderline index when everything else is totally fine, etc.

 

[sevoflurane]

I am not debating about utility of TEE as a diagnostic mode, I am saying that TEE has same inadequacys as PA catheter in guiding hemodynamic managements. As far as complications of PA catheters are concerned the incidence of serious complications with PA catheters is 0.016% and only 1 in 2000 of these compications is directly related to PA catheter and most of them to accesing venous system. So if you are already puting in a central line the added complication involved with floating a PA catheter and not wedging ( I do not wedg) it is very minimal. Most of the complications involved are mainly because of lack of knowlage to inteprete the results which can happen with both the monitors.
As far as I am concerned, PA catheter still has place in hemodynamic managment if you know how to use it

Sounds good. For a second I thought you were saying that TEE offers very limited befefit to the patient and that it adds significant risk.

The morale of the story is always that PA caths provide very little benefit to a patient and do add risk.

So dose the TEE

Like all monitors, you need to know how to use them correctly in order to get the most out of them. Carry on.

 

[deleted171991]

I just ordered it off Amazon because of this thread.

Look what I found: Evidence-Based Critical Care (3rd edition), coming in December 2014. They must be crazy if they think anybody will pay $140 for it.