Atrial pacing above 100 to increase CO/MAP

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Specializes in Critical Care.

I am brand spanking new in the Surgical ICU at a level 1 trauma center. I've been a nurse for 2 years on general surgery so please excuse me but I am just curious. I'm brushing up on all things ICU right now - currently reading Essentials of Critical Care as endorsed by the AACN.

I had a POD 1 CABG that was still in SICU because of MAPs that would not sustain above 60. By the time we came into morning report the night nurse had titrated the Levophed to 0.2 from what he had left the patient at which was 0.07 with a MAP of about 65 - 70. With Levophed at 0.2 her MAP was barely 62 - 65. The CT surgeon proceeded to raise the temporary atrial pacing to 110 and instructed us to lower the Levophed and wean her off completely.

Eventually we did and her MAP sustained at 62 - 66 with the HR set to not fall below 110. Then she stopped making urine, unfortunately I did not return the next day to find out what happened but given her UOP dropped I think (and I know I'm just new) she needed some fluids.

Is it best practice to raise the HR so much on a CABG? In my mind I think I want to let their heart rest not put more oxygen demand.

Experienced ICU nurses enlighten me

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Specializes in Critical Care.

Cardiac output is the volume of blood the heart pumps with each beat times the number of beats, so given the same volume pumped, more beats equals more CO. But the faster the heart beats, the less volume it's able to fill and pump with each beat, so increasing heart rate will only increase CO so long as it's able to fill enough to still be beneficial. Usually we might pace at 80 or even 90 to improve CO, but I've never seen 110 be beneficial, if it is then they are pretty volume depleted and you'd get more benefit from volume. The best way to find that sweet spot of filling time and HR, along with an arterial line MAP, is a continuous CO/CI, although old-school manual thermodilution will still work. Usually we increase the paced rate until we reach our goals or until it's no longer getting us closer to our goals, then fix what's wrong; the patient needs more volume, they need less afterload, etc.

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Specializes in Critical Care.
Cardiac output is the volume of blood the heart pumps with each beat times the number of beats, so given the same volume pumped, more beats equals more CO. But the faster the heart beats, the less volume it's able to fill and pump with each beat, so increasing heart rate will only increase CO so long as it's able to fill enough to still be beneficial. Usually we might pace at 80 or even 90 to improve CO, but I've never seen 110 be beneficial, if it is then they are pretty volume depleted and you'd get more benefit from volume. The best way to find that sweet spot of filling time and HR, along with an arterial line MAP, is a continuous CO/CI, although old-school manual thermodilution will still work. Usually we increase the paced rate until we reach our goals or until it's no longer getting us closer to our goals, then fix what's wrong; the patient needs more volume, they need less afterload, etc.

Makes perfect sense! A faster HR can potentially mean decreased ventricular filling time?

Yeah we gave albumin bolus after bolus - I think X4.

Unfortunately they came from the OR with no PA catheter.

Thanks!

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Makes perfect sense! A faster HR can potentially mean decreased ventricular filling time?

Yeah we gave albumin bolus after bolus - I think X4.

Unfortunately they came from the OR with no PA catheter.

Thanks!

You can get a cardiac output and stroke volume variation from a flotrac/vigileo with just an A line. You don't need a swan to get titratable hemodynamic measurements.

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Specializes in Critical Care.
You can get a cardiac output and stroke volume variation from a flotrac/vigileo with just an A line. You don't need a swan to get titratable hemodynamic measurements.

I will look these up and ask about them at my facility. Never heard of but then again I've only been in ICU for roughly a month. Thanks so much! Learned something new ;)

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Cardiac output: The amount of blood the heart pumps through the circulatory system in a minute.

The heart can only pump the volume available. Increasing the heart rate is useless in this case and increases O2 demand.

CT surgeons need to know when to stop playing their god card card.. and consult cardiology.

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Specializes in Critical Care.
Cardiac output: The amount of blood the heart pumps through the circulatory system in a minute.

The heart can only pump the volume available. Increasing the heart rate is useless in this case and increases O2 demand.

CT surgeons need to know when to stop playing their god card card.. and consult cardiology.

Thank you so much, you validated my initial thoughts. :)

I take it some CT surgeons are highly opposed to consulting cardiology? I heard around the unit there's some beef between CT and Cardiology and who gets to make what decisions. Heard it's a hot mess.

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Specializes in Critical Care.

He ordered dobutamine next (renal dose) and ordered 20 of lasix to be given bc of the decrease in UOP

I disagree with these orders but I am also new so don't want to stir waters.

How is the lasix or renal dose of dobutamine going help if the issue was fluid deficit? I bet she was in serious need of fluids and I think we should have first checked her H/H.

Obviously the albumin wasn't cutting it? I wish I was there the next AM to see the whole chain of events.

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Thank you so much, you validated my initial thoughts. :)

I take it some CT surgeons are highly opposed to consulting cardiology? I heard around the unit there's some beef between CT and Cardiology and who gets to make what decisions. Heard it's a hot mess.

Most of the time the surgeon can correct the structural defect. It takes the expertise of a cardiologist to "manage acute and chronic congestive heart failure, acute myocardial infarction and other acute ischemic syndromes, acute and chronic arrhythmias, preoperative and postoperative patients".

Cardiovascular surgeons,as all surgeons ..feel they they sit at the right hand of God. All cardiovascular surgery patients deserve cardiology on board.

In this case, as the nurse.. you knew the surgeon was not giving you the correct orders. Time to go up the chain of command.

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He ordered dobutamine next (renal dose) and ordered 20 of lasix to be given bc of the decrease in UOP

"I disagree with these orders but I am also new so don't want to stir waters. "

How is the lasix or renal dose of dobutamine going help if the issue was fluid deficit? I bet she was in serious need of fluids and I think we should have first checked her H/H.

Obviously the albumin wasn't cutting it? I wish I was there the next AM to see the whole chain of events.

I disagree with these orders but I am also new so don't want to stir waters.

To Hades with stirring up the waters . Your patient is being mismanaged.

Cojones are now required.

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Specializes in Critical Care.

In this case, as the nurse.. you knew the surgeon was not giving you the correct orders. Time to go up the chain of command.

Thank you and I will do next time, new or seasoned in the ICU - I think my patient deserves the best and a cardiology consult would have made a difference. Thank you for your insight.

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Specializes in Critical Care.

Cojones are now required.

I agree! I had some good cojones in general surgery by the time I left, time to put on some ICU cojones!

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