NRB Flow Rate

[Shishkabob]

So, tell me then, aside from the lack of an Oxygen reservoir, and one way valves, what the physical difference is between an NRB and SFM, just so everyone can understand. Because clearly I'm missing something quite obvious that every Paramedic should know and learn back in medic school for you to make the hub-bub.

 

[Journey]

So, tell me then, aside from the lack of an Oxygen reservoir, and one way valves, what the physical difference is between an NRB and SFM, just so everyone can understand. Because clearly I'm missing something quite obvious that every Paramedic should know and learn back in medic school for you to make the hub-bub.

Linuss, that reservoir bag is there for a reason just as the reservoir bag or tail on a BVM.

A simple mask can be ran at as low as 6 liters because it does not have the reservoir mask. The reservoir bag has a capacity of 600 - 1000 ml. I think you might also have been attempting to describe is a partial rebreathing mask. A partial rebreathing mask allows gas exhaled in the initial phase of exhalation to return to the reservoir bag. As exhalation proceeds, the expiratory flow rate declines, and when the expiratory flow rate falls below the oxygen flow rate, exhaled gas can no longer return to the reservoir bag. The initial part of expiration contains gas from the upper airways (anatomic dead space) so the gas rebreathed is still rich in oxygen and contains very little CO2. So, maintaining adequate flow because of that bag is still important.

The one way valve on a nonrebreather prevents any exhaled air from returning to the reservoir bag.

You can check the accuracy of my description of these two masks with just about any nursing, critical care or respiratory therapy book if you can not the info in a Paramedic book. The manufacturers willl also have a description and instructions on the proper use of these masks. This is not something that is difficult to look up and you should learn the proper use of each device on your truck regardless of what it is.

This isn't hearsay or street medicine or whatever you want to call it. Manufacturers design, test medical devices and print instructions for a reason which is to take the mystery out of the use of these things so patients will achieve maximum benefit and not be harmed by their use.

 

[AnthonyM83]

As an FYI, not all companies include instructions of any kind in the masks' wrappings. Many have only a company name and listings of parts included with patent info. No further description or images.

Also the EMT and paramedic curriculums AND textbooks seem to have a very poor coverage of how each device works. Also I believe previous poster was referring to the side valves in reply to my post, not the reservoir bag's valve.

 

[usafmedic45]

A simple mask can be ran at as low as 6 liters because it does not have the reservoir mask.

Actually it can be done that because the mask is not a sealed system like an NRB (or to a lesser extent, a PNRB ) so the person can entrain atmospheric air to meet their metabolic needs beyond what the oxygen flow is delivering.

You can check the accuracy of my description of these two masks with just about any nursing, critical care or respiratory therapy book if you can not the info in a Paramedic book.

Didn't need to break out my RT textbooks.

 

[Journey]

Actually it can be done that because the mask is not a sealed system like an NRB (or to a lesser extent, a PNRB ) so the person can entrain atmospheric air to meet their metabolic needs beyond what the oxygen flow is delivering.

The aerosol mask with the larger side ports would be better for entraining air and meet the definition of high flow. At my hospital we can run a high flow system with 2 - 35 liter aerosols giving 70 liters and still allow the patient to entrain enough air to meet their flow demands and maintain some consistency in FiO2. We can utilize this system in the ICUs, tele and in the ED if there is an extended hold time and the patient is not a candidate for BiPAP/CPAP.

There are newer masks on the market such as the OxyMask which can eliminate some of the mistakes commonly made in and out of the hospital. We have eliminated the NRB and simple masks from the med surg floors to prevent running the masks at too low of a flow or accidental disconnects which leaves the patient unmonitored with their face in a plastic mask especially if they are not able to call for help. They may not be getting the oxygen they need but they may still have a chance by breathing through the large ports of the OxyMask.

Didn't need to break out my RT textbooks.

Maybe not since you are a Respiratory Therapist. However, it seems some are going by what they've heard or probably information that may have been posted on these forums by those who have not bothered to learn why or how from credible sources.

As an FYI, not all companies include instructions of any kind in the masks' wrappings. Many have only a company name and listings of parts included with patent info. No further description or images.

Check with the person who does your supplies. Usually there will be a spec and literature sheet in each case. You can also request it from the manufacturer through their website if it is not already posted.

 

[usafmedic45]

Maybe not since you are a Respiratory Therapist. However, it seems some are going by what they've heard or probably information that may have been posted on these forums by those who have not bothered to learn why or how from credible sources.

Geez...I was trying to be funny.

At my hospital we can run a high flow system with 2 - 35 liter aerosols giving 70 liters and still allow the patient to entrain enough air to meet their flow demands and maintain some consistency in FiO2.

A jet nebulizer system?

We have eliminated the NRB and simple masks from the med surg floors to prevent running the masks at too low of a flow or accidental disconnects which leaves the patient unmonitored with their face in a plastic mask especially if they are not able to call for help.

Honestly if someone needs a simple mask or NRB, they probably don't have any business being on the floor and need to be in the ICU.

 

[Journey]

Geez...I was trying to be funny.

It is hard to tell on this forum.

A jet nebulizer system?

Thera-mist

They've been around for many, many years.

AquinOx for high flow NC up to 35 liters.

Honestly if someone needs a simple mask or NRB, they probably don't have any business being on the floor and need to be in the ICU.

A simple mask at 6 liters is maybe 0.40 and our policy says move the patient to a higher level after 0.50 if there is not a chance of reversing the situation. The physicians can still decompress or tap a chest and insert chest tubes on the floors to alleviate some problems as well as giving diuretics. There are also some patients who are DNR with a do not transfer to ICU order but that does not mean we will not continue to treat or make comfortable at least until more medications can be given to get a handle on the air hunger feeling which may have nothing to do with the pulmonary system but whatever works for the moment until the other systems can be supported or comforted. Microsurgery may also want some their replants or grafts hyperoxygenated for 24 hours.

We prefer to assess each situation and allowing for a clinical decision rather the following recipes.

 

[usafmedic45]

Thera-mist

Yeah, the nurses around here just call them "jet nebs" which I am not entirely fond of but it's the terminology they choose to use and I gave up correcting them years ago. I'm not paid enough to do that and if they do something that harms a patient or could potentially do so, I let the administration deal with it.

We prefer to assess each situation and allowing for a clinical decision rather the following recipes.

Same here but as a general rule, if they are sick enough to need to be on above 44% O2 (a 6 L/min cannula) they are significantly ill enough to go to an ICU or an intermediate care unit. If you're talking about something that can be rapidly reversed, that is obviously an exception to transferring the patient, but when I say "need" higher flow O2, I'm referring to those patients with complicated pathology that is not amenable by simply doing thoracentesis or giving some furosemide. Our hospital's policy is that if the patient has a chest tube, they have to be in an "acute care" (ICU or intermediate care) unit and not out on the floor.

 

[Journey]

Our hospital's policy is that if the patient has a chest tube, they have to be in an "acute care" (ICU or intermediate care) unit and not out on the floor.

There are patients who have recurrent pleural effusions and even a recurrent pneumothorax that do not need an ICU bed. Our med-surg RNs are capable of handling chest tubes and whatever oxygen equipment that can be used on the floors. We may also have ALS patients on BiPAP on the med-surg floors if they are not in the hospital for an acute respiratory problem other than their ALS.

 

[usafmedic45]

There are patients who have recurrent pleural effusions and even a recurrent pneumothorax that do not need an ICU bed.

We don't get many of those out on the floor. Most of our chest tubes are inserted in the emergency room or are in place for post-operative drainage.

Our med-surg RNs are capable of handling chest tubes and whatever oxygen equipment that can be used on the floors.

Likewise. I don't fully understand the reasoning for the chest tube policy and don't pretend to.

We may also have ALS patients on BiPAP on the med-surg floors if they are not in the hospital for an acute respiratory problem other than their ALS.

We put patients like that over in the acute care unit which is technically part of our hospital's rehabilitation arm but is used as a "step-down" from the ICU to the med/surg unit.

 

[Melclin]

@USAF

I see you didn't avail yourself of the delights of frivolous parlour conversation in your time away from the forums

 

[Phlipper]

@USAF

I see you didn't avail yourself of the delights of frivolous parlour conversation in your time away from the forums

He does seem rather wound up, doesn't he? I generally don't pay attention to screen names and can be arguing with someone one minute and then gabbing with them one post later. It's the internet. No one with a real life takes it seriously. But USAF does, indeed, seem to need a little time away somewhere quiet. He's getting pretty wrapped around the axle on every thread. If I noticed his screen name and all the vitriol, it's definitely an issue.

Now, for something of substance: since we have learned a low flow NRB is borderline criminal, what are the 'approved' methods of treating hyperventilation, in the absence of other, more significant issues?

 

[Melclin]

He does seem rather wound up, doesn't he? I generally don't pay attention to screen names and can be arguing with someone one minute and then gabbing with them one post later. It's the internet. No one with a real life takes it seriously. But USAF does, indeed, seem to need a little time away somewhere quiet. He's getting pretty wrapped around the axle on every thread. If I noticed his screen name and all the vitriol, it's definitely an issue.

Now, for something of substance: since we have learned a low flow NRB is borderline criminal, what are the 'approved' methods of treating hyperventilation, in the absence of other, more significant issues?

Not at all what I meant.

It was taking the p*ss.

 

[Journey]

Now, for something of substance: since we have learned a low flow NRB is borderline criminal, what are the 'approved' methods of treating hyperventilation, in the absence of other, more significant issues?

If you have a POC machine you can check an ABG (arterial blood gas - if arterial sticks are in your scope of practice) to confirm hyperventilation which is a decrease in arterial CO2 (PaCO2). You can also check other labs if you have the cartridges to check for other forms of acidosis which are not readily obvious.

You can attempt to calm the patient but for some with a profound metabolic acidosis which you may not know about, dropping their pH can be life threatening when they slow their respiratory rate or you force them to rebreathe their CO2 or increase their work of breathing which will also add to the acidosis systemically.

There are several young people, 14 - 24, that are coming to the ED with a new onset of DKA. They had no idea they were diabetic and are in a panic when they feel they have lost control of their breathing. It is probably a very weird feeling and they probably don't feel well or the tingling sensation doesn't help. The first thing some want to do is write them off an a psych case or anxious teenager and stick their face into a plastic mask with little or no flow or tell them to get a ride with a friend.

You also have to remember a person who is breathing fast may not be hyperventilating at all and their CO2 might be rising. This is true for infants, peds and patients with chronic lung diseases as well as metabolic disorders.

Any terms and information I have provided can easily be looked up in any nursing or critical care book and may also be found on credible websites.

 

[Phlipper]

If you have a POC machine you can check an ABG (arterial blood gas - if arterial sticks are in your scope of practice) to confirm hyperventilation which is a decrease in arterial CO2 (PaCO2). You can also check other labs if you have the cartridges to check for other forms of acidosis which are not readily obvious.

You can attempt to calm the patient but for some with a profound metabolic acidosis which you may not know about, dropping their pH can be life threatening when they slow their respiratory rate or you force them to rebreathe their CO2 or increase their work of breathing which will also add to the acidosis systemically.

There are several young people, 14 - 24, that are coming to the ED with a new onset of DKA. They had no idea they were diabetic and are in a panic when they feel they have lost control of their breathing. It is probably a very weird feeling and they probably don't feel well or the tingling sensation doesn't help. The first thing some want to do is write them off an a psych case or anxious teenager and stick their face into a plastic mask with little or no flow or tell them to get a ride with a friend.

You also have to remember a person who is breathing fast may not be hyperventilating at all and their CO2 might be rising. This is true for infants, peds and patients with chronic lung diseases as well as metabolic disorders.

Any terms and information I have provided can easily be looked up in any nursing or critical care book and may also be found on credible websites.

That's why I wrote "in the absence of other, more significant issues". Interesting info on DKA. I have noticed even in my small town service we are checking bg more and more and I am trying to understand all the different ways db issues present. Good info to know. Thanks.

Let me try it this way: pt presents with what looks like hyperventilation and medic has ruled out more serious issues - checked BG, they're on a monitor w/capno, etc. and medic says "You can take this one." At this point he wants me to jump in the back, document as much info as I can, and treat the pt for hyperventilation on the way to the ER. What can/should I, working as a Basic only, do for the pt? Grab a plastic bag/brown paper bag? Do nothing and let ER handle it when we get there? What do you guys (experienced medics) suggest? What would you want to see a basic do?

 

[Journey]

That's why I wrote "in the absence of other, more significant issues". Interesting info on DKA. I have noticed even in my small town service we are checking bg more and more and I am trying to understand all the different ways db issues present. Good info to know. Thanks.

Let me try it this way: pt presents with what looks like hyperventilation and medic has ruled out more serious issues - checked BG, they're on a monitor w/capno, etc. and medic says "You can take this one." At this point he wants me to jump in the back, document as much info as I can, and treat the pt for hyperventilation on the way to the ER. What can/should I, working as a Basic only, do for the pt? Grab a plastic bag/brown paper bag? Do nothing and let ER handle it when we get there? What do you guys (experienced medics) suggest? What would you want to see a basic do?

ABG means Arterial Blood Gas, not blood glucose. You can not actually confirm a true hyperventilation without knowing a PaCO2. (arterial measurement of CO2). Even an ETCO2 might not be accurate depending on the mismatching and gradient of the arterial to End Tidal measurements.

I would not advise using a paper bag but that might still be in your protocols.

 

[jrm818]

Let me try it this way: pt presents with what looks like hyperventilation and medic has ruled out more serious issues - checked BG, they're on a monitor w/capno, etc. and medic says "You can take this one." At this point he wants me to jump in the back, document as much info as I can, and treat the pt for hyperventilation on the way to the ER. What can/should I, working as a Basic only, do for the pt? Grab a plastic bag/brown paper bag? Do nothing and let ER handle it when we get there? What do you guys (experienced medics) suggest? What would you want to see a basic do?

Just as a note not at all relevant to the original scenario, but I wouldn't think that end tidal capnography is sufficient to exclude the possibility of arterial hypercapnia as the cause of tachypnea (I presume the reasoning behind including ETCO2 as part of the assessment is that if "ETCO2 is normal/low, there must be arterial hypocapnia and thus we are seeing maladaptive hyperventilation and not adaptive tachypnea due to arterial hypercapnia). In patients with lung disease ETCO2 may not represent arterial CO2 due to poor ventilatory function. Of course if our pt. has a low ETCO2 because they are inadequately ventilating, they are probably actually hypercapniac due to inability to shed CO2. I would consider reducing such a patient's minute ventilation or forcing them to re breathe CO2 would be in rather poor form.

I don't know how common this presentation is, and I have no data to support my supposition, but I would think that treating tachypnea as hyperventilation on the basis of ETCO2 readings is fraught with peril. It seems to me that the primary use would be in confirming hypercapnia with observation of high ETCO2, rather than ruling out disease with observation of low/normal ETCO2.

 

[Veneficus]

Likewise. I don't fully understand the reasoning for the chest tube policy and don't pretend to.

Sure you do, for the money of course. Why bill for a standard bed when you could bill for an ICU stay.

Of course the other answer may be that the nurses get all bothered about somebody needing something as "complicated" as a chest tube so they have an excuse to turf the pt. to somebody else.

You know the medical playbook, punt on first down to remove yourself from responsibility and doing any more work than the absolutely minimum required to stay employed while professing to be a superhero healthcare provider.

 

[Journey]

Sure you do, for the money of course. Why bill for a standard bed when you could bill for an ICU stay.

Of course the other answer may be that the nurses get all bothered about somebody needing something as "complicated" as a chest tube so they have an excuse to turf the pt. to somebody else.

You know the medical playbook, punt on first down to remove yourself from responsibility and doing any more work than the absolutely minimum required to stay employed while professing to be a superhero healthcare provider.

If you need an ICU bed, we will try to get you one even if it means transferring patients to another hospital if necessary. If a patient is critical and needs an ICU bed, you should not consider that turfing. If a policy says a patient with a chest tube must go to the ED, that also should not be considered as turfing. It might be different in EMS where you can only take to the nearest ED and have the hospital sort out the appropriate level of care. The wallet biopsy also seems to be a concern for some in EMS on this forum and is used to decide what level of care the patient deserves or if they even deserve care.

While sometimes it seems we can't do as much as we would like in the hospital, just doing the minimum should not be a standard. EMS really needs to get beyond this minimum thing.

 

[Veneficus]

If you need an ICU bed, we will try to get you one even if it means transferring patients to another hospital if necessary. If a patient is critical and needs an ICU bed, you should not consider that turfing. If a policy says a patient with a chest tube must go to the ED, that also should not be considered as turfing. It might be different in EMS where you can only take to the nearest ED and have the hospital sort out the appropriate level of care. The wallet biopsy also seems to be a concern for some in EMS on this forum and is used to decide what level of care the patient deserves or if they even deserve care.

While sometimes it seems we can't do as much as we would like in the hospital, just doing the minimum should not be a standard. EMS really needs to get beyond this minimum thing.

I am not talking about EMS.

Wallet biopsy is alive and well in hospitals too. Many times inacted as policy by administrators.

My favorite is a private hospital that removed all of it's inner city OB resources to wealthy suburbs so that those needing immediate OB care (like delivery) could meet the transfer criteria for services not available onsite. Very clever. Not very altruistic.

"Needs" are often relative and policy as a form of fixed rule rarely takes that into account.

"critical" is also one of those relative terms that means different things to different people. So while I agree if the patient needs the ability and resources of an ICU, they should have it.

Rules, are mearly guidlines.

There are few conditions that are not served better from a medical standpoint in the ICU. Figure, more resources, highly skilled providers, extremely small provider/patient ratio.

In referencing USAFs comment, a chest tube shouldn't always and automatically mean an ICU. A policy requiring such is not based on a medical standpoint. The comfort or ability of nursing staff is not a medical issue, nor are the economics of billing.