Nitro in Right Sided Cardiac Compromise?

[scope2776]

Hello! I'm a Paramedic student and I would like to have a discussion and hear your thoughts on the administration of nitroglycerin to patients with right-sided heart failure, either chronic or acute. It has been my experience on this topic that many doctors, nurses and paramedics have differing views. As a result of special circumstances, my class is co-taught by two professors this year; and they even have differing opinions. There are many knowledgeable and experienced medics on this board and I would like to hear what you have to say!

For chronic heart failure I'm thinking about the patient whom you are called to for "cardiac concerns", with obvious signs of right sided failure - such as swelling, JVD, jugular reflex, cardiac history and such. But not signs of pulmonary edema, etc.

For acute failure I'm thinking about the patient with chest pain that has Atrial Infarct (rare), or inferior wall MI with right sided involvement.

Per our protocols nitro is contraindicated for patients with a sys BP < 100. So giving nitro to these patients who have come to this point (cardiogenic shock) is out of the question. I know nitro can have a significant impact on the patient's preload, and the treatment of choice for any hypotensive pt is fluid. Here we only have SL (0.4 mg) spray, no nitro drips.

My question is, per your experience, what have you done with patients who are right on the cusp? With like a sys of 110 upwards? Has it been your experience that nitro has bottomed these people out particularly quickly? Or do you wait on their pressure?

My question on the chronic patients is do you continue fluid therapy even if sys is above 100 to try and increase preload as much as possible to help the heart? Or do you just go ahead and give niro per protocol? (Given of course no other contraindications to fluid are present.)

My question for the acute patients with CP is first do you give nitro after a line has been established, but before you do a 12 lead? Or do you wait until after a 12 lead, when there pressure is around 110-130 sys, to rule out inferior MI? Also is your goal to give fluids until there pressure is good enough to give nitro or not give nitro at all?

I have relatively little experience in the field and have a good grasp on the mechanisms at work, but am kinda looking for what your experiences on the street have been with this. Thanks!

[Thunderchild145]

Eh. This is obviously an opinions question, and also slightly dependant on protocols. Our protocols say no nitro without an IV line, and nothing below 90 systolic. If it's 90, yes. If it's 88, then no. Since I'll typically give a nitro before I get an EKG, my first "To give or not to give" is based solely on BP.

In either case, we'll administer fluid to a patient with a BP of <90 systolic, at this point I'll grab my EKG, and per protocols will administer nitro when the pressure reaches or exceeds 90, excepting cases where a diagnostic EKG can reveal acute right sided compromise, or the historian (pt or otherwise) can reveal chronic right sided compromise. Protocols here say no nitrates for people who are preload dependant. Same for morphine.

As far as to what happens when you do give nitro to RVI patients, yes. It's been my experience that if bottoms them out fairly quickly. I'll typically pucker my buttcheeks and squeeze the IV bag as hard as I can. For chonic patients this drop seems to be less dramatic, and I've noticed that most patients who are chronically preload dependant are typically hypertensive to begin with.

[Ridryder 911]

NTG is not contraindicated in right sided AMI's as many attempt to claim. Now, with that said, it would be illogical to administer it to a patient and potentially cause a hypotensive event and thus increasing oxygen demand and potentially increasing infarct size.

I personally rather obtain a XII lead prior to any NTG administration, to prevent administration to a right sided or inferior wall AMI. It does not take long to obtain, and by the time ASA therapy begins, my ECG should be accomplished.

Usually, (not always) one might see lower blood pressures associated with inferior wall, but not necessarily so. I personally still withhold NTG in such cases. In non-right side AMI, I prefer to keep them slightly normotensive ot slightly hypotensive (the old CCU nurse in me) and have no problems administering NTG with systolic pressures > 90 mm/hg.

I have found a slight bolus (250 ml) or so actually increases preload in some right sided AMI and will actually decrease their pain. The old saying, if NTG and Morphine is making the pain worse, give some fluid and check to see if you have a right sided AMI.

R/r 911

[AZCEP]

I'm not sure I understand your question scope.

If I'm reading it right, you want information on management differences between chronic and acute right heart failure. Is this right?

The chronic patient will likely already be on some degree of diuresis and possibly a long acting nitrate, like isosorbide. It would also be expected to have an ACE inhibitor or ARB in the mix. These patients are not ususally as sensitive to the preload reduction that the acute patients are, due to their body acclimating to the many different treatments that are already being used.

The acute situation is quite different. These patients have not built up a tolerance to any specific treatments, and will respond much more dramatically to what you will try. Using a blood pressure number to decide to use NTG is a bit troublesome. The sensitivity of the patient to the agent will have a more significant effect than what their initial pressure is. If you start with a low pressure, but their are no signs of end organ problems, NTG may well be considered. You might pretreat with some fluids first, but don't eliminate the option based on one number. Using IV infusions of NTG is much preferred in the right side involved patient, due to the ability to titrate to effect.

The signs of a right sided MI can be quite different from other chambers of the heart as well. Where anterior and lateral MI's become tachycardic and hypertensive, the right side will be bradycardic and normo- to hypotensive. The anterior and lateral areas progress to this, while the right side begins this way. The XII lead is the best tool you have to add information to your assessment for this situation. If you see signs of inferior wall involvement, consider the possibility of the right side being included.

[scope2776]

Wow! Great responses! Thank you very much... I understand where you guys are kinda coming from now.

As far as to what happens when you do give nitro to RVI patients, yes. It's been my experience that if bottoms them out fairly quickly. I'll typically pucker my buttcheeks and squeeze the IV bag as hard as I can. For chonic patients this drop seems to be less dramatic, and I've noticed that most patients who are chronically preload dependant are typically hypertensive to begin with.

It seems the common consensus is to withhold nitro for acute right sided compromises, or be prepared to deal with a more serious drop in BP.

I personally rather obtain a XII lead prior to any NTG administration, to prevent administration to a right sided or inferior wall AMI. It does not take long to obtain, and by the time ASA therapy begins, my ECG should be accomplished.

I think i will be more comfortable doing a XII lead before NTG admin in the future, unless the pressure is 150 sys +. You're right it dosen't take long at all to do a quick XII lead.

Using IV infusions of NTG is much preferred in the right side involved patient, due to the ability to titrate to effect.

Yep! That's exactly the question I was asking, thank you. I have heard great things about nitro drips... a department close to hear has them. Do your departments have nitro drips? I've heard you can only do them with a pump, as it turns out to be like 2-4 gtts/min.

[AZCEP]

Most places do not have the option of NTG infusions due to the volatility of the solution. It tends to not do well from a shelf life perspective in EMS.

We do not have this option, but it is one that should be considered as you are working your patient's condition into a plan. It does work very well, and EMS can provide some basic treatments that will ease the transition to the infusion.

http://members.ozemail.com.au/~jamesbc/pages/drugs/122.htm

Obviously, the drip rate that is set will be determined by several things. The patient's condition, response to the medication, the concentration you have on hand, and the drip set used would be some of them. The site I've referenced is from Australia, so the terminology will be a bit different, but the information holds.

[elvismedic]

I was taught to obtain a 12 lead prior to NTG. I start off with 4 81mg chewable ASA. Then proceed to IV access while BLS is assessing vitals. If I have changes in II, III, and AvF then I obtain a right-sided 12 lead. I would withhold NTG for R sided heart failure as the R ventricle is pre-load dependent. I would start off with a bolus of fluid to see if that improves the patients pain.

[Medic26]

Well lets see,

In ACS or chest pain cases we are supposed to complete a 12-lead prior to any treatment including oxygen, personally I administer oxygen if the look bad or if they are in obvious distress. I also give ASA while applying the monitor to get that out of the way.

As far as NTG in right vs. left CHF.............our protocol is NTG for Pulmonary Edema and chest pain as long as they have a pressure > 100 systolic. We have had this debate at our company because we have a PA (works for cardiology in local clinic) who is also a paramedic for over 15 years as well. He try's to preach the whole fluid instead of NTG, but our medical director likes us to stick with the protocol. If there pressure drops < 100 systolic we give them fluid anyway and withhold NTG.........problem solved.

Personally I believe if you have providers trying to figure out Right vs. Left sided failure you will have incorrect or delayed treatments in more cases than you have now by sticking to the standard treatments. But, this is only my OWN view!

[Rezq304]

NTG is not contraindicated in right sided AMI's as many attempt to claim. Now, with that said, it would be illogical to administer it to a patient and potentially cause a hypotensive event and thus increasing oxygen demand and potentially increasing infarct size.

I personally rather obtain a XII lead prior to any NTG administration, to prevent administration to a right sided or inferior wall AMI. It does not take long to obtain, and by the time ASA therapy begins, my ECG should be accomplished.

Usually, (not always) one might see lower blood pressures associated with inferior wall, but not necessarily so. I personally still withhold NTG in such cases. In non-right side AMI, I prefer to keep them slightly normotensive ot slightly hypotensive (the old CCU nurse in me) and have no problems administering NTG with systolic pressures > 90 mm/hg.

I have found a slight bolus (250 ml) or so actually increases preload in some right sided AMI and will actually decrease their pain. The old saying, if NTG and Morphine is making the pain worse, give some fluid and check to see if you have a right sided AMI.

R/r 911

My feelings exactly Rid. If I have the equipment available to me, why not go straight for a 12-lead. Takes less than 60 seconds to obtain & can prevent NTG administration to a normo-tensive patient where the right ventricle is compromised.

[letsgonational]

If I'm thinking that the pt is AMI, they're getting:

O2/Vital signs

324 ASA PO

Monitor/IV access

NTG after IV access with bp checks q 3 minutes

12 lead EKG

A total of three NTG (including home NTG) and then 4mg Morphine via IV. Morphine is repeated 1mg q 5 minutes.

We transmit our 12 lead, notify the ER of a stat cath, and get them to the ER ASAP. We strive for 2 dual lumens or a total of 4 IV sites...cath lab loves us:-) 911 to open time is usually less than the 90 minute door to open time, except for long distance transports...gotta love rural EMS.

Time is muscle, no need for a 12 lead before ASA and NTG if your pt is presenting with cardiac symptoms. I run as a single paramedic provider on a squad and I can get the entire list of things done in less than 10 minutes. Then we twiddle our thumbs and wait for the ambulance! Long story short. Never withold NTG if you think your pt is AMI. If you're thinking right sided AMI, call command after you obtain your 12 lead, hang saline, and get orders for NTG. Dont fluid overload them though...that just makes their heart work harder thus increasing ischemia and infarct.