# Repeat Nitro dosing Question



## Madmedic780 (Mar 29, 2011)

In my defense I tried searching and asking this question before posting so sorry if it's been said here, but:

I'm an Intermediate Student and most protocols in my area (Oregon) say OLMC is required (for both I's and P's) if you want to give more than 3 doses of Nitro to patients C/O chest pain. For us we have kinda long transport times (45 minutes to an hour) and generally have to call in for this rather often.

However I couldn't find a satisfactory answer as to why we are limited to only 3 doses, nor have I heard of a physician refusing extra nitro at the paramedic's request. 

I thought so long as we monitor the HR and BP well that nitro was rather safe, is there something I'm missing with regards to sudden toxicity or adverse side effects in more total doses?

Please enlighten.


----------



## Veneficus (Mar 29, 2011)

Silverman780 said:


> In my defense I tried searching and asking this question before posting so sorry if it's been said here, but:
> 
> I'm an Intermediate Student and most protocols in my area (Oregon) say OLMC is required (for both I's and P's) if you want to give more than 3 doses of Nitro to patients C/O chest pain. For us we have kinda long transport times (45 minutes to an hour) and generally have to call in for this rather often.
> 
> ...




Sounds like your system needs to discover nitro paste or drips.


----------



## MrBrown (Mar 29, 2011)

Brown was taught unless it continues to relieve their pain, repeated GTN is inappropriate.


----------



## Farmer2DO (Mar 29, 2011)

Veneficus said:


> Sounds like your system needs to discover nitro paste or drips.



Nitro paste I would support.  Nitro drips?  You would have to have a lot of confidence in your paramedics.  Even with a pump, a paramedic needs a decent understanding of, and needs to be comfortable with, titrations of infusions.  I would not be comfortable giving IV NTG to most of the paramedics in my system.  I would prefer that they all be able to read 12 lead EKGs proficiently first, and not just parrot the computer interpretation.  When they write in their chart "possible MI, age undetermined" you know that they have NO clue how to read them.

In our system, we our limited to 6 before a medical control call.  The reason is that they want 1) someone confirming the strong suspicion of ACS 2)consideration of further treatment (metoprolol, morphine) and 3) the hospital to be aware of an acute patient inbound.  1-2 hour drop times for EMS, while not the norm, are not uncommon in our system.  All of our hospitals except 1 will try to clear and hold a bed for such a patient, and 2 of our 4 EDs see >100,000 patients per year.  If we give #7, does that mean hell to pay?  Nope. Probably wouldn't even warrent a comment at my agency.


----------



## Veneficus (Mar 29, 2011)

Farmer2DO said:


> Nitro paste I would support.  Nitro drips?  You would have to have a lot of confidence in your paramedics.



If I actually aspired to become an EMS medical director, my paramedics would be the standard by which excellence was measured. But that is not on my "to do" list.




Farmer2DO said:


> Even with a pump, a paramedic needs a decent understanding of, and needs to be comfortable with, titrations of infusions.



Every parramedic I have taught for 8 years is proficent with titrations and infusions.



Farmer2DO said:


> I would not be comfortable giving IV NTG to most of the paramedics in my system..



I am sorry.



Farmer2DO said:


> I would prefer that they all be able to read 12 lead EKGs proficiently first, and not just parrot the computer interpretation.  When they write in their chart "possible MI, age undetermined" you know that they have NO clue how to read them.



Reading a 12 lead is subjective, I have had cardiology electrophysiologists teach me more than I will ever remember about reading them. Truthfully, I know of no EMS system that uses them anywhere near their full value.


----------



## Bieber (Mar 29, 2011)

I think it's something of a vestigial fear (and not one entirely unfounded) that paramedics will continue to give nitro irregardless of the patient's blood pressure.

In practice, after three doses of nitro it's probably time to start considering narcotic pain relief, and if you're in a very enlightened system the likes of which I've never so much as seen from a distance, you'll have been using a nitro drip from the get go.


----------



## EMSrush (Mar 29, 2011)

Bieber said:


> I think it's something of a vestigial fear (and not one entirely unfounded) that paramedics will continue to give nitro irregardless of the patient's blood pressure.



I agree. Calling in is an extra safety net.


----------



## STXmedic (Mar 29, 2011)

Here we do:

Chest pain/STEMI- NTG x3, if it is relieving pain then we can continue until BP drops < 100mmHG. If it is ineffective, we move to narcs.

CHF/Acute PE- Double dose NTG cont'd as long as BP > 100 or until the pt loses a palpable radial pulse.

No medical control contact is required for either. We are talking about NTG drips, but nowhere near implementation.


----------



## Shishkabob (Mar 29, 2011)

Meh, if you need to call after 3 times that'd be a good time to discuss options with the doctor on the other end.  Don't view it as a limit, but as a time where consultation wouldn't hurt.


We have drips at my agency, but I'm not opposed to discussing options with a doc if the pain persists after nitro.




Really, I prefer drips over SL and patches.  More control, more consistency, and can stop it pretty darn quick if you need to... but always have a dedicated NS line if you're doing a NTG drip.


----------



## WolfmanHarris (Mar 29, 2011)

Our dosage:

NTG 0.4mg SL q 5 min up to 8 doses until symptoms resolved. Discontinue when BP falls below 100 mmHg systolic or by more than one third from initial pressure or Pt. HR <60 or >160bpm.


----------



## Bieber (Mar 29, 2011)

We have standing orders for nitro PRN every five minutes as long as the BP remains >100 mmHG, but after three doses of nitro I move on to fentanyl (which is also standing order 1 mcg/kg repeat in 15 min to a total of 2 mcg/kg).

Linuss, I'm not so familiar with nitro drips.  I think there's only one agency around these parts that uses them.  Are they difficult to titrate (as in, an infuser is a must have) or what?  Like Farmer2DO said, there seems to be a lot of fear about paramedics using them.  So what's the deal?

Also, do you know how much more effective are they with regards to morbidity/mortality as opposed to SL or topical nitro?


----------



## Farmer2DO (Mar 29, 2011)

Bieber said:


> We have standing orders for nitro PRN every five minutes as long as the BP remains >100 mmHG, but after three doses of nitro I move on to fentanyl (which is also standing order 1 mcg/kg repeat in 15 min to a total of 2 mcg/kg).
> 
> Linuss, I'm not so familiar with nitro drips.  I think there's only one agency around these parts that uses them.  Are they difficult to titrate (as in, an infuser is a must have) or what?  Like Farmer2DO said, there seems to be a lot of fear about paramedics using them.  So what's the deal?
> 
> Also, do you know how much more effective are they with regards to morbidity/mortality as opposed to SL or topical nitro?



My opinion?  NTG drips are not difficult to manage at all.  They're not weight based, which takes that out of the equation.  Titratable and quickly weaned as needed.  You need to watch MAP, HR and your patient's clinical response.  I would trust handing them to MAYBE 20% of the paramedics in my region tomorrow.  After some training, maybe a total of 50-60%.  I'm in a region with a lot of agencies and a lot of small districts, and some very weak paramedics.  

In response to Veneficus, you're right about EKGs being subjective.  But I'm using that as an example.  The same people that don't know the significance of Q waves vs. T wave inversion vs. ST segment elevation vs. ST segment depression, in fact don't even know what contiguous leads are, are the people that I would NOT trust to give IV NTG.  When the hospital asks you "What is your dopamine running at?", you reply "90", and they ask "90 what?", a response of "90 systolic" because you don't know how to calculate drips is an issue.


----------



## usalsfyre (Mar 29, 2011)

Bieber said:


> Linuss, I'm not so familiar with nitro drips.  I think there's only one agency around these parts that uses them.  Are they difficult to titrate (as in, an infuser is a must have) or what?  Like Farmer2DO said, there seems to be a lot of fear about paramedics using them.  So what's the deal?
> 
> Also, do you know how much more effective are they with regards to morbidity/mortality as opposed to SL or topical nitro?



NTG infusions aren't hard to use at all. However, they do require pumps. Honestly if your running medicated infusions, they should be on a pump. For some reason we think it's ok to run a pressor by hand, but not NTG. This is not to say you don't need to know how to calculate or titrate drips by hand. Our pumps are "dumb" pumps, meaning they do no calculations for you. As Farmer2DO noted, it requires watching a couple of physiologic parameters while your titrating it. Which there's a fair number of paramedics who can't be trusted to do this. 

As far as EBM, I'm not sure it's even been studied. However I can say that IV NTG is a much more tirtratable and I feel safer form of nitrate therapy. It can be delivered in much lower or higher doeses based on patient response, can be delivered continuously as opposed to Q5, no break in CPAP is needed for APE therapy, ect. Studies might be nice, but shouldn't overwhelm what is intuitively obvious, espescially when your dealing with the same medication via a different route.


----------



## Aidey (Mar 30, 2011)

MrBrown said:


> Brown was taught unless it continues to relieve their pain, repeated GTN is inappropriate.



How many doses are you giving before declaring that it isn't working?


----------



## Outbac1 (Mar 31, 2011)

If nitro sl doesn't work for relieving pain after three doses we move to ms. Most of our emergency transports are too short to get into nitro drips. However we do take a number of pts on long transports to the cath lab (100 - 140mi away) quite often. In fact I took one yesterday. The pt was on it since the 27th and had been pain free since going on it. Before that they couldn't manage the frequent onsets of pain. The pt had gone in on the 26th with cp. No ecg changes and no elevated trops or creatine. Those came later. Hx was a 3 vessel bypass 6 years ago and had been symptom free since then. A nitro drip certainly worked for this pt.


----------



## Veneficus (Mar 31, 2011)

I think the point of the OP is that if it is working, why is there not a standing order for a maintenence?

I don't think anyone is advocating to keep dosing nitro when it has no effect.


----------



## the_negro_puppy (Apr 1, 2011)

Our protocols state GTN every 5 minutes while pain symptoms exist, HR 50-150, systolic BP > 100 no max dose, sub-lingual only


----------



## Trevor (Apr 3, 2011)

You know what the best thing about NTG is? The half life! So what if you drop someone's BP? As long as your paramedics recognize this and dont drop it any further... AND as long as its not profound hypotension (MAP<70 for an extended time)... 

Our guidlines allow us to give NTG q5 minutes as needed, we can also move to Fentanyl (with a max of 300mcg total) if we want. We used to be able to give Valium in addition for "anxiety related to pain" however, recent changes have now made that an online order. 

The problem with ACS is that if someone is hurting BP and HR both go up in response to the pain. As we all know, increased BP/HR=increased workload for the heart and increased O2 demand. Couple that with ischemic tissue and you've (or more specifically the patient) got a problem...

Not to mention the idea of keeping someone in pain, when we have the tools to fix it, is a bit... Archaic...


----------



## 18G (Apr 3, 2011)

I don't agree with the 3 doses of NTG and then call MC. How is persistent SL dosing different then continuous infusion through a drip? I understand there are differences obviously from SL to IV, but the same principle applies which is continuous. 

We give continuous SL NTG as long as pressure supports it. If the patient is still having pain after three doses we give MS or Fentanyl but still continue with the SL nitro.

Here, 911 is not allowed to initiate NTG drip... we can only monitor and adjust inter-facility as needed.


----------



## orange20medic (Apr 3, 2011)

Everytime I've seen a patient get 3 doses of NTG, it normally drops their blood pressure below 90 systolic. In our protocols, if BP <90 systolic, NTG is contraindicated. So would it really even be necessary to give over 3 doses?


----------



## Trevor (Apr 3, 2011)

hmmmm.... I VERY RARELY get a significant drop in BP with NTG... Specially to <90 SBP


----------



## Icenine (Apr 3, 2011)

Here basics have NTG q5 as long as it's relieving pain and bp is >100 systolic.

There are no provisions for drips or paste.

ALS has Morphine and Fentanyl.


----------



## zmedic (Apr 4, 2011)

Be aware that mainly agencies or counties just take the state protocols, which are written for a large group of providers. I'm sure the states perspective is that most providers have relatively short transport times, like under 30 minutes. So if the nitro works, three doses should keep them pain free to get to the hospital, and if it doesn't work, they should be trying something else. 

Also not to beat a dead horse, but nitro doesn't decrease mortality. So why the big push to be able to give lots of nitro without calling in? Are you really so busy during your hour transport time that it's a huge pain to call?


----------

