# CHF and nitrates



## emtkrak (Oct 5, 2007)

I'm an EMT almost done w/ medic school.  I was working for a BLS service the other day and we were dispatched for resp distress.  Long story short, 69 y/o CHF hx, lasix 40mg bid, orthopnea, increased distress on exertion, lung sounds decreased w/ rails, pitting edema, obvioulsy CHF here.  Vitals were a-fib rate 80s, BP 164/68, and resp 36 initally w/ SPO2 RA @ 89%.  We did the BLS stuff, O2 quick load and go, and met up w/ the medics.  The medic agreed w/ my assessment and field dx of CHF.  He however did not agree w/ my treatment ideas.  Pt SPO2 was 98% w/ NRBR, I thought that the Pt needed nitrates and lasix.  Per protical Pt should have recived 2 SL nitro (at the same time) and 40mg of lasix.  The medic however said that the Pt's problem was not hypertension related and did not need the nitrates.  Pt was given 100mg Lasix IV and tx emergent mode (30 min tx time) w/ minor changes en-route.  Can anyone explain to me why this Pt shouldnt have recieved nitrates?  I thought it would decrease preload, afterload, and O2 demand on the heart making it pump more effectively, as well as open up the vasculature and helping pull fluid off the lungs.  What does the hypertensive issue have to do with anything?  Thanks for the help!


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## Ridryder911 (Oct 5, 2007)

Actually, both of you were wrong. 

The current recommended treatment and research has shown those with CHF and complications of such should recieve CPAP ASAP! This has shown to provide better relief and reversal than Nitrates and Lasix.

I do agree with administration of NTG. However; there is no recommendation of a determine amount of dosages. Personally, 0.4mg (1/150 grain) is okay, but needs to be cautiously administered. Personally, I prefer NTG IV, or 1" topical to allow a slower administration, but bucossa spray is acceptable as long as there is not a right sided or inferior wall involvement. Causing an increase in preload will only cause problems... Remember, in CHF we are not treating so much the HTN, rather we should be focusing on the "pump failure" monitoring preload and afterload affects. The HTN is a side effect of preload inability to increase ejection fraction. 

CPAP has been shown and demonstrated to reduce intubations by half and ICU admissions almost by that number.. it is the best thing in a few years in EMS. 

Administration of Lasix in the prehospital setting is very controversial. I personally like it because of the shifting, if one is > 20 minutes from a hospital setting, and they are in Frank CHF (presence of pulmonary edema) however; it is now beginning not to be recommended unless you are certain it is CHF and have a delayed transport. It is estimated up to 80% of  administration of Lasix is inappropriate in the field, either by tx CHF when it is not, or wrong dosages (already previously on home Lasix). 

Good luck on your studies.. I suggest to perform a search on current treatment in the literature.. 

R/r 911


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## triemal04 (Oct 5, 2007)

Well dude, this pt didn't get nitro because the medic didn't feel like giving any.  Silly basic, questioning what the medic says.  

On a serious note, from what you said there is no valid reason why the guy should not have been given nitro.  Unless there is something out of the ordinary that you left out, that's pretty much as close to a "classic" CHF'er as you're going to see.  Treating with lasix is great, especially with the long transport, but nitro given repeatedly (or IV if you're lucky enough to have that) would have had a much quicker effect.  For the reasons you've said.  Just always be aware of their BP; generally with CHF you won't have a huge drop in their pressure, but it can happen, and when it does it makes a bad situation so much worse.

Edit:  If you can, track down the medic and talk to him.  I'm curious what the responce will be.


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## emtkrak (Oct 5, 2007)

C-pap was not indicated per our protocols due to Pts SPO2 being above 90% w/ O2 therpay.

And our protocol for CHF states the following for nitro:

3 SL tablets for SBP > 180
2 SL tablets for SBP 140 - 180
1 SL tablet for SBP 100 - 140

NTG may be repeated every 3-5 min as long as BP is greated than 100 systolic.

Yes, that means that if the Pt's bp is 180 systolic, they get 3, if in 5 minutes their bp is between 140-180 they get 2 more...  

its a huge debate over here

as far as lasix, Pts only get it if they already take it, and they get their home does up to 100mg


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## Ridryder911 (Oct 5, 2007)

emtkrak said:


> *C-pap was not indicated per our protocols due to Pts SPO2 being above 90% w/ O2 therpay*.
> 
> And our protocol for CHF states the following for nitro:
> 
> ...



They need to re-research their CPAP protocol and make changes. Why wait for sat's to drop? It is much more effective than NTG and Lasix.. that would be like waiting for the lungs to fill up with fluid... again, it has been proven to be the most effective treatment in the emergency setting. 

We have changed our protocol for CPAP for all major respiratory distress. I placed it on a septic patient with harsh rhonci.. amazing results. I am sure Vent can testify on the results of CPAP. 

R/r 911


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## emtkrak (Oct 5, 2007)

I know.  Our protocols are very very strange.  The ones I am talking about just went into effect in July.  The ones before this were worse.

The state protocols have C-pap listed way towards the bottom, but our regional protocols say under 90%.  

For some reason the region's override the states...?

I agree, I really like c-pap, and I've used it a lot during clinicals!


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## So. IL Medic (Oct 16, 2007)

Well, I have points of agreement and disagreement with some posts. 

Our system protocols for a CHF crisis state:
CPAP if available, Lasix can be 0.5mg - 1.0mg/kg, or standard dose 20-40mg, 2.5mg Albuterol NEB, 0.4mg NTG SL.

As to why, CPAP is proving to be effective in maintaining effective respiration, Lasix for reducing blood volume to pull volume from lungs, NTG for increasing the circulatory volume and pulling fluid from lungs and for its effect on increasing the effectiveness of the capillary beds around the alveoli as one doc explained to me.

As to how far down the chain of the protocol you go depends on the patient, transport time, and your judgement. Some pts just need the O2 assist of CPAP, more severe pts need a full court press.


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## skyemt (Oct 16, 2007)

disagreements aside, Rid is quite correct in his comments....

a couple of notes...
researching is showing that there is research showing that CHF is being overdiagnosed and overtreated in the field, with adverse effects...

secondly, the research on CHF induced pulmonary edema is changing...the current thinking is shifting, in that it is not necessarily a case of fluid overload, but rather a fluid "redistribution" into the alveoli, due to high pressures in the pulmonary capillary system...

CPAP is effective, because it keeps the alveoli pressurized, and forces fluids back into the capillary system out of the lungs... this is why you can have very positive results without overly medicating... CPAP is also indicated in non-cardiac pulmonary edema, addressing the problem of differential diagnoses...

i belive, with a more detailed explanation, that this is what Rid was getting at in his posts.


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## VentMedic (Oct 16, 2007)

CPAP has been successfullly treating CHF and other respiratory problems for more than 50 years. Actually, I believe the history books have it scientifically going back to the 1930s.  Anybody see Dr. Forrest Bird on 60 Minutes a couple weeks ago?

CPAP is also used in the home care not only for sleep apnea but for chronic CHF patients. Usually these machines are running on 21% O2.  Many of the older hospital CPAP machines rarely did above 35%. So, it is the effects of intrathoracic pressure on fluid distribution and splinting the alveoli rather than the actual oxygen that makes the difference. Someone can be 100% SpO2 and still working hard. 

CPAP uploads the respiratory muscles by splintling the alveoli thus requiring less energy to reopen.  This can work well on a variety of respiratory problems. 

CPAP increases intrathoracic pressure, reducing preload and afterload and improving cardiac output. 

In the normal heart where cardiac output is largely preload dependent, CPAP decreases cardiac output by reducing LV preload but without reducing afterload. In contrast, because cardiac output in the failing heart is relatively insensitive to changes in preload but very sensitive to reductions in afterload, CPAP-induced reductions in LV transmural pressure can augment cardiac output. 

CHF is summarized best as an imbalance in *Starling *forces or an imbalance in the degree of end-diastolic fiber stretch proportional to the systolic mechanical work expended in an ensuing contraction. This imbalance may be characterized as a malfunction between the mechanisms that keep the interstitium and alveoli dry and the opposing forces that are responsible for fluid transfer to the interstitium. 

You will have the accumulation of fluid with a low-protein content in the lung interstitium and alveoli, when pulmonary veins and left atrium venous return exceeds left ventricular output. 

The lymphatic system keeps the lungs dry. An acute rise in pulmonary arterial capillary pressure may increase filtration of fluid into the lung interstitium, but the lymphatic removal does not increase correspondingly.

People got into the habit in the 1970s and 80s of visualizing "pushing fluid back into the capillary system" without understanding the opposing forces responsible for fluid transfer . Thus, we ended up with a fiasco known as "Super PEEP" which actually utilized PEEP up to 100 cmH2O. That is how high the old water PEEP columns were back in the day.  

In preHospital CPAP, there are people are again thinking more (higher CPAP cmH2O) is better rather than having an understanding of pulmonary capillary pressure and plasma oncotic pressure as well as the lymphatic system. They are thinking in terms of "pushing" the fluid back.  One could also throw in a little understanding at the basic level of BP and venous return.

CPAP is an excellent tool but caution again to ensure your device doesn't increase the work of breathing rather than assist it. Not all CPAP devices are created equal. Understand how your device entrains gas to provide the flow.

Agreed, Lasix is given too guickly to the dehydrated elderly patient who may have PNA, CHF or both.


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## spidermedic (Dec 28, 2007)

I hate to say this, but your preceptor skipped NTG because he didn't know what he was doing as  evidenced by administering 100 of Lasix. 

The problem many medics have is that they automatically assume that rales=fluid overload. This is often not the case and many of these people have a relative hypovolemia from the 3rd spacing of fluid.

One of the problems with Lasix, along with those already mentioned, is that for the first 10-15 minutes after admin is actually increases preload. Definitely not what you're trying to accomplish.

While people have been pushing early CPAP,  and rightly so, the papers are also calling for aggressive nitrate therapy. Hit them with sprays and then hang a drip--Some papers are recommending quickly getting up to > 200 mcg/min.


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## MasterIntubator (Jan 6, 2008)

Our normal treatment plan for the symptomatic CHFer...

O2, +/- albuterol ( has worked beautiful many of times in conjuction with the other meds ), IV, NTG x1, Lasix ( 40mg or double their home dose ), 2mg Morphine.

Repeat as necessary

( until we get our CPAP )


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## Grady_emt (Jan 7, 2008)

Here's ours:

Albuterol to get you going, Sublingual nitro up to 3, Nitro Paste, Lasix 40 if not on at home, 80 if on at home, 2-4 of morphine standing order.  That usually starts to improve their condition, our average RLS transport is 7 minutes.

We are "supposed" to be geting CPAPs on all our trucks, but they have suppose4d to have been coming for six months.


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## spidermedic (Jan 7, 2008)

Interesting about the albuterol. All of the studies I've looked at give albuterol a "meh" and caution that it may also increase preload.

As far morphine, there is absolutely no  studies that support the efficacy of morphine in CHF and it's associated with a higher number of intubations as well as longer stays. People still give it because we had always been told it decreases preload, which is does, but only an insignificant amount (<80 ml)

In  NH, we just eliminated morphine from the CHF protocol and  Furosemide is being limited to a max of 40mg. (Lasix also has it's problems in the prehospital setting)

Cheers All


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## MSDeltaFlt (Jan 7, 2008)

Here's something else to remember about symptomatic CHF'ers::censored: The classic problem is pulmonary edema which impedes breathing.:censored: That's "B" people; not "C".:censored: Giving NTG either SL or IV is great.:censored: It dilates quickly to shift the fluid from the lungs back into the rest of the body.:censored: It does it quickly so be careful.:censored: Hitting them with 2 shots off the bat might be dangerous.:censored: Like Ridryder said, they might have some major cardiac issues that make it difficult to compensate.CPAP, or even BiPAP, actually SHOVE the fluid back; thus improving "B".:censored: And giving a CHF'er an Albuterol neb makes absolutely no sense to me.:censored: Why give fluid to lungs that are full of fluid?:censored: If it wheezes (auscultated; not audible), give Alb.:censored: If it's rales, give NTG/CPAP/BiPAP... maybe Lasix.Now I'm old school RT.:censored: The only neb I like to give someone in CHF is ethenol.:censored: It actually breaks down the viscocity of the Pulm Ed.Just my 2 cent's worth.


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## spidermedic (Jan 7, 2008)

MSDeltaFlt said:


> If it wheezes (auscultated; not audible), give Alb.:censored:



Can't quite agree with you on that one as it's not uncommon for the wheezes to precede or even mask the rales. Basically if they're afebrile with no hx of COPD or asthma, but do have pedal edema or a CHF Hx, I'm hitting them fairly aggressively with NTG.

BTW, what' with all the censored things in you're post?


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## bonedog (Jan 7, 2008)

The confusion is the constriction in CHF is due to increased hydrostatic pressure, in COPD you are dealing with true broncho constriction. 

Reduce the load, dilate the vessels, relieve the stretch on the heart and everything will fix it self, no broncho dilators needed.



Studies show increased M&M with morphine and lasix.... relieve the stretch and the kidneys will function normally with out the changes in electrolytes.


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## MSDeltaFlt (Jan 7, 2008)

spidermedic said:


> Can't quite agree with you on that one as it's not uncommon for the wheezes to precede or even mask the rales. Basically if they're afebrile with no hx of COPD or asthma, but do have pedal edema or a CHF Hx, I'm hitting them fairly aggressively with NTG.BTW, what' with all the censored things in you're post?



Rales = fluid.  Get rid of the fluid.  Wheeze = constriction.  Open them up.  Keep it simple.  Don't over think it.

As far as the censored thingy's; I don't have the foggiest notion as to what I'm doing wrong on posting.  I'm not cussin'.  Honest.


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## katgrl2003 (Jan 8, 2008)

Wish we had CPAP on our trucks, but the only people in central Indiana that have it are the helicopters.

-Kat


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## Ridryder911 (Jan 8, 2008)

Shame CPAP is not being introduced more in EMS. It is much safer and effective than any pharmacological effects. We (my state) have started allowing Basics to start CPAP therapy. 

Personally, I have held off Morphine since studies have demonstrated an increase in pulmonary congestion. Yes, it is hard to get used to but; times change. I do still administer Lasix after NTG. We are attempting to obtain a NTG IV drip in the field protocol. Personally, I would like to see more IV NTG or NTG paste along with CPAP therapy. 

Hopefully, EMS will dedicate CPAP as an essential equipment tool. It has been proven to reduce admission rates and ICU admissions, one of the best true treatments that we can actually make a difference. 

R/r 911


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## skyemt (Jan 8, 2008)

i know NYS is working on bringing CPAP into the protocols, but i've heard it will be for ALS only...


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## spidermedic (Jan 9, 2008)

MSDeltaFlt said:


> Rales = fluid.  Get rid of the fluid.  Wheeze = constriction.  Open them up.  Keep it simple.  Don't over think it.



It's really not a matter of over thinking...a beta-2 is simply not going to reverse airway constriction secondary to edema, and may increase preload.  

Personally, I think medics need to do a bit _more_ thinking on how they address respiratory issues. All the wheezes is not asthma and all that crackles is not HF.


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## byun01 (Jan 10, 2008)

*Reasons behind treatment*



ridryder 911 said:


> Actually, both of you were wrong.
> 
> The current recommended treatment and research has shown those with CHF and complications of such should recieve CPAP ASAP! This has shown to provide better relief and reversal than Nitrates and Lasix.
> 
> ...



I am going to have to agree with ridryder that CPAP is a treatment of choice.  However, I understand many services do not carry CPAP.  On another note, I think we should discuss the reasons behind treating CHF.  And as always, if anyone has a concern or disagreement, we can use this opportunity to learn from each other.  Anway, back to CHF.  CHF can be caused by a MI that ultimately reduced the ejection fraction of the left ventricle.  Ultimately this causes a backup into pulmonary vein and into the lungs.  When a patient, caused by a number of reasons (osmotic pressure), complains of difficulty breathing they are literally drowning in his or her own fluid.  Lasix is a diuretic and MOST IMPORTANTLY TO REMEMBER is that it takes about 20min to achieve a therapeutic level.  As a result, if lasix is the only drug you provide, they will still complain of difficulty breathing.  Ultimately, it is Nitro that will provide fast relief (let's not forget oxygen).  Nitro is a smooth muscle vasodilator.  Veins have no/very little smooth muscles.  Rather arteries depending on how close you are to the heart, have tons of smooth muscle.  By providing the patient nitro, you expand the arteries making it easier for the patient's heart to eject blood.  In short, *assuming there was no contraindication*, the paramedic should have given both nitro and lasix along with BLS.


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