Without evidence of benefit, an intervention should not be presumed to be beneficial or safe.

- Rogue Medic

Corrections of Misleading Charts Comment – Part I

In response to Corrections of Misleading Charts, there was this response from Can’t say, clowns will eat me

So, I’m assuming you mean to say that we can actually give unlimited NTG to hypertensive CHF patients? What?!?! But, the NTG will surely bottom out their pressure. We can’t give that. The risks are too great. We need to leave the BP where it is and certainly we’re too stupid to know when it’s hypertension, much less CHF vs pneumonia vs ACS……….

Every day I ask, Mirror, mirror, on the wall. Who’s the most sarcastic of them all. Usually I get a satisfyingly sycophantic response and I go about my ripped from a Charles Adams sketch day. Not so, when this comment appeared. My sarcasm has been slacking. PS Can’t say, when the nice little old lady offers you the apple, go ahead and take a bite. 🙂

So. I have been humbled, but how should I respond?

The comment is perfect.

Furosemide (Lasix) allows medical directors and medics to feel as if they are doing something, but nothing as dangerous as giving NTG.

The irony is that the appropriate use of furosemide (for CHF) is probably a lot more dangerous than NTG, even if the inappropriate use of NTG.

What would be inappropriate use of NTG?

1. Giving NTG to a patient who does not have CHF (or chest pain).

The patient’s blood pressure may drop for a little bit and then recover. If NTG is not indicated, it should not be given, but will this cause as much harm to these patients as the harm we would cause by giving furosemide boluses to CHF patients?

I don’t think so.

Harm from furosemide in CHF?!?!?!?

Yes.

I do not have proof, but there is no good reason for EMS to be using furosemide.

Here is an example of the problem. From the very first EMCrit podcast, very short podcast (10 1/2 minutes), Dr. Weingart says –

It’s not going to help you and it’s very potentially going to hurt you. No Lasix in these patients. Now, I’m sure your EMS providers have already given it. Well, that’s just fine, but you don’t have to exacerbate the problem. Most of these patients will end up volume depleted, not volume overloaded when you look at their intravascular space. You’re probably going to end up giving fluid to these patients, not trying to diurese them. The problem is not fluid overload.

If the problem is not fluid overload, and as Dr. Weingart clearly says –

The problem is not fluid overload.

Then, I have to ask –

Why are so many of us giving a drug just to treat fluid overload?

2. Giving NTG to a hypotensive patient who does not have CHF.

The blood pressure may drop even more. If NTG is going to worsen hypotension, it definitely should not be given, but will there be as much harm to these patients as there would be from giving furosemide boluses to any CHF patients?

I don’t know.

Will there be as much harm to these patients as there would be from giving furosemide boluses to hypotensive CHF patients?

I don’t know.

I don’t expect to see any studies of giving NTG to hypotensive non-CHF patients, normotensive non-CHF patients, or even to hypertensive non-CHF patients. The attitude of the IRBs (Institutional Review Boards) toward medical treatments appears to be, Don’t ask. Don’t tell.

3. 2. Giving NTG to a hypotensive patient who DOES have CHF.

Is this inappropriate?

To be continued in Corrections of Misleading Charts Comment – Part II and in Corrections of Misleading Charts Comment – Part III.

Some of the evidence that supports this –

Prehospital therapy for acute congestive heart failure: state of the art.
Mosesso VN Jr, Dunford J, Blackwell T, Griswell JK.
Prehosp Emerg Care. 2003 Jan-Mar;7(1):13-23. Review.
PMID: 12540139 [PubMed – indexed for MEDLINE]

Free Full Text PDF

Modern management of cardiogenic pulmonary edema.
Mattu A, Martinez JP, Kelly BS.
Emerg Med Clin North Am. 2005 Nov;23(4):1105-25. Review.
PMID: 16199340 [PubMed – indexed for MEDLINE]

Free Full Text PDF

EMCrit Podcast 1-Sympathetic Crashing Acute Pulmonary Edema
EMCrit
by Dr. Scott Weingart
Podcast

Supplementary documentation on CHF treatment

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