Co monitoring

CbrMonster

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super basic question in reality but can't seem to google fu the answer,

but lets say

using a zoll x advanced with co monitoring capabilities using the finger probe

say pt spo2 is 100%, Co reads 19 does that theoretically mean their real o2 saturation is 100-19=81% ? or is there a specific formula or ?
 

MackTheKnife

BSN, RN-BC, EMT-P, TCRN, CEN
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super basic question in reality but can't seem to google fu the answer,

but lets say

using a zoll x advanced with co monitoring capabilities using the finger probe

say pt spo2 is 100%, Co reads 19 does that theoretically mean their real o2 saturation is 100-19=81% ? or is there a specific formula or ?
I assume you are talking about the Zoll EtCO2 function? There's no "formula" as CO2 is separate from O2. If you want actual O2 level, then you want ABGs. If the person is on room air, then their SpO2 should be 100% using the PF Ratio formula.
 
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CbrMonster

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I assume you are talking about the Zoll EtCO2 function? There's no "formula" as CO2 is separate from O2. If you want actual O2 level, then you want ABGs. If the person is on room air, then their SpO2 should be 100% using the PF Ratio formula.
no, our pulse oximeter can also monitior co levels, not talking etco2
 

MackTheKnife

BSN, RN-BC, EMT-P, TCRN, CEN
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no, our pulse oximeter can also monitior co levels, not talking etco2
That's an amazing feature. But there's no formula to extrapolate or "correct" O2 like there is for QT intervals.
 

DesertMedic66

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That's an amazing feature. But there's no formula to extrapolate or "correct" O2 like there is for QT intervals.
It’s actually a pretty common feature that can be added to multiple EMS cardiac monitors when your company initially buys them.
 

Carlos Danger

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super basic question in reality but can't seem to google fu the answer,

but lets say

using a zoll x advanced with co monitoring capabilities using the finger probe

say pt spo2 is 100%, Co reads 19 does that theoretically mean their real o2 saturation is 100-19=81% ? or is there a specific formula or ?
You are basically correct. A CoHB of 19% means that 19% of available hemoglobin binding sites are occupied by carbon monoxide. That doesn't necessarily mean that your Sp02 is 81%, though - it's a little more complex than that, owing to changes in hemoglobin affinity for oxygen molecules when some binding sites are already occupied by CO and also the fact that a "normal" Sp02 can be less than 100% anyway.

Unless those monitors are smart enough to compensate for that; I am not very familiar with them. When you use those monitors, do the Sp02 level and COHb level always add up to 100%?
 

NomadicMedic

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The way the sensor measures SpO2 or CO is by the frequency of the light waves. There’s no way to extrapolate the difference between CO and O2 using a finger probe.

I find the the clinical presentation of CO poisoning is supported by a measured metric, not the other way around. You’ll find smokers with an elevated CO, doesn’t mean it’s clinically significant.
 

NomadicMedic

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No. The Rad 57 measures each individually and provides individual metrics. If you want absolutes, get an ABG. I’d use it as nothing more than a tool to rule in/rule out CO and treat appropriately.

They say it themselves, “
SpCO is not intended to be used as the sole basis for making diagnosis or treatment decisions related to suspected carbon monoxide poisoning; it is intended to be used in conjunction with additional methods of assessing clinical signs and symptoms.”
 

Carlos Danger

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No. The Rad 57 measures each individually and provides individual metrics. If you want absolutes, get an ABG. I’d use it as nothing more than a tool to rule in/rule out CO and treat appropriately.

They say it themselves, “
SpCO is not intended to be used as the sole basis for making diagnosis or treatment decisions related to suspected carbon monoxide poisoning; it is intended to be used in conjunction with additional methods of assessing clinical signs and symptoms.”
So that device does not provide a COHb level?Just looking for clarification. I am not familiar with these monitors or the technology that they use, but I’ve known for some time that they exist.

As for the disclaimer, that could be applied to pretty much any diagnostic device or test. It doesn’t mean the device isn’t reliable; they wouldn’t be selling it if they didn’t have good data to that effect.
 
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NomadicMedic

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Carlos Danger

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I would not use it for anything more than a indicator. And really, does it directly have any effect on your care? Suspect CO? Oxygen.
Well, yeah....it's an indicator like any other monitoring device. But my question wasn't about where these devices should or shouldn't fit into any clinical decision making. I was confused when you wrote "There’s no way to extrapolate the difference between CO and O2 using a finger probe." when in fact there is.
 
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