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

- Rogue Medic

The NNT and Merit Badge Meds

Mon, 04 Oct 2010 10:22:51 -0400 by
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Perhaps I am too negative in my interpretation of the research on ACLS medications. What about a more objective assessment – one with a more statistical view of the harms and benefits?

How many patients have to be treated with ACLS (Advanced Cardiac Life Support) drugs in order for one patient to benefit (be resuscitated) from the treatment?

The NNT is a very interesting site. The information is prevented much more succinctly than I usually describe things.

Why NNT?

NNT is a common medical term.

NNT is the Number Needed to Treat – the average number of patients we would need to treat with something in order for one patient to benefit. The flip side is NNH.

NNH is the Number Needed to Harm – the average number of patients we would need to treat with something in order to harm one patient.

This is explained in more detail (including a less than 4 minute YouTube video for those who don’t want to read a lot) at the NNT Explained page. Understanding the material presented in the video is very important for understanding the actual benefit of a treatment, rather than the potential benefit that is given by those promoting any treatment.

Once you understand this, you will be able to see that many treatments require huge numbers of participants because the NNT is so large. A large NNT means a small benefit (in numbers). Just because only a small number of patients benefit, does not mean that the benefit is small. The amount of benefit for those who do benefit is also important. This is one of the reasons we spend so much time treating cardiac arrest.

While the NNT for cardiac arrest is large, the benefit is lives saved. There are few benefits as important as that. As the method of CPR improves, the NNT drops because the treatment helps more patients. The NNT is a great site to look around and get a quick idea of the relative benefits of many different treatments. Go browse the NNT.

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Filed Under: Critical Judgment, Heresy, Pharmacology, Research Tagged With: , ,

Furosemide and Drug Shortages 2

Thu, 30 Sep 2010 22:37:28 -0400 by

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Also posted over at Paramedicine 101, which is now at EMS Blogs. Go check out the excellent material there.

I will keep pointing out the problems with furosemide (Lasix) and the evidence against it. Let’s ignore the problems with giving furosemide to patients who actually have CHF/ADHF (Congestive Heart Failure/Acute Decompensated Heart Failure). Can medics correctly identify CHF/ADHF?

The EHS ePCR database identified paramedic reports in which furosemide was administered. As furosemide only appears in the CHF/pulmonary edema protocol, paramedic differential diagnosis of this was assumed by furosemide administration. Data abstraction from the EHS ePCR and ED chart included the EP primary diagnosis, considered the gold standard. Other data points collected included: demographic information; EHS treatment administered; treatment administered in the ED; adverse events and patient disposition.[1]

They do not describe their method of selecting the charts.

Was it completely random?

Was it sequential?

How did they select their sample?

There were three objectives of this study. The first was to determine agreement between paramedic administration of furosemide with EP diagnosis of CHF. The second was to examine differences in interventions administered by paramedics and in the ED by EP diagnosis of CHF. The third objective was to identify any adverse events that occurred during patient care.[1]

How much agreement on CHF/ADHF diagnoses?

It should be noted that seven patients without an ED diagnosis of CHF received ED furosemide and 43 patients received ED nitro with only eight of those having a primary diagnosis of ACS. This data put the accuracy of the primary ED final diagnosis as a reference standard into question, as it appears CHF may have been in the differential diagnosis for many patients not ultimately diagnosed with CHF. Secondary diagnoses were not sought out and included. Therefore, paramedic accuracy reported in this study may be falsely low, if CHF was part of the EP secondary diagnoses. It should also be noted that there were two patients with a diagnosis of “shortness of breath not yet diagnosed.” It is possible that these patients did indeed have CHF, but were not diagnosed until a later time during hospital care. This needs to be considered when determining paramedic diagnostic accuracy.[1]

OK. For some reason, the emergency physicians gave furosemide to 21% of the patients they diagnosed with something other than CHF/ADHF. That may be explained by the CHF/ADHF being a secondary diagnosis.

This is something that should have been included in the study. What was being treated and for what reason. From the way they describe their data, they had the actual ED physician chart, not just a diagnosis. This is something they should include in a follow-up study, especially with a larger sample size.

Since two of the patients had the diagnosis shortness of breath not yet diagnosed I will move them to the CHF/ADHF side of the graph. After all, most of the patients were diagnosed with CHF/ADHF.

That looks so much better.

On the other hand, there are problems with the way they conclude that some patients do not have CHF/ADHF. How much higher would things be if secondary diagnoses were included?

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It should be noted that seven patients without an ED diagnosis of CHF received ED furosemide and 43 patients received ED nitro with only eight of those having a primary diagnosis of ACS. This data put the accuracy of the primary ED final diagnosis as a reference standard into question[1]

What does NTG (NiTroGlycerin) have to do with ACS (Acute Coronary Syndrome), when examining CHF/ADHF treatment?

NTG is the most effective medication for hypertensive CHF/ADHF. Go listen to the EMCrit CHF/ADHF podcast if you doubt me. For those not hypertensive, this research certainly suggests that NTG should be studied.

NTG is not just for chest pain.

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Data abstraction from the EHS ePCR and ED chart included the EP primary diagnosis, considered the gold standard.[1]

Maybe. Maybe not. And don’t get me started on Gold Standards.

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ED mortality was higher in patients with an alternate diagnosis than those diagnosed with CHF by the EP (2/60 vs. 6/34, p=0.017). As documented on ED charts, eight patients in this sample suffered adverse events other than death. These adverse events were: hypotension (n =3), heart rate problem (n =3), electrolyte imbalance (n =1), and respiratory effort decline (n = 1). All of the patients who suffered adverse events were diagnosed with CHF by the EP. Adverse events were not associated with the amount of nitroglycerin, morphine or furosemide administered.[1]

Adverse events in the ED were documented as occurring as often as death in the ED. Almost all of the deaths were in the group not diagnosed with CHF/ADHF, but all of the adverse events occurred in the group diagnosed with CHF/ADHF.

Of the six patients with an alternate diagnosis who had an outcome of death, three were diagnosed with pneumonia. Eight adverse events other than death were identified in this sample. Interestingly, all these patients were correctly identified as having CHF, which contradicts previous research which has found adverse events were more likely in patients incorrectly treated for CHF by paramedics.11,12 This indicates that furosemide should be administered with caution, even in cases where diagnosis of CHF is correct.[1]

Where is the evidence that furosemide should be administered, even if the diagnosis of CHF/ADHF is correct?

What would we want to know?

Did the patients have peripheral edema when given furosemide by EMS. Even with peripheral edema, furosemide is far from the first line drug, but without peripheral edema, it is not going to do anything good.

These patients need the best treatment possible, not the most persistent hold out from the Dark Ages.

We have known that CHF/ADHF is not primarily a fluid overload problem since the 1980s.

Why is EMS still using furosemide?

Is there any problem with a shortage of furosemide?

Not at all, but this isn’t the study to prove it.

I hope the authors use what they learned from this to design a definitive study of the prehospital use of furosemide.

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Updated 02-07-11 to correct the uselessness of the original charts I made for this post.

More details are in Corrections of Misleading Charts.

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Footnotes:

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[1] Correlation of paramedic administration of furosemide with emergency physician diagnosis of congestive heart failure
Thomas Dobson, Jan Jensen, Saleema Karim, and Andrew Travers.
Journal of Emergency Primary Health Care
Vol.7, Issue 3, 2009
Free Full Text . . . . . . . Free Full Text PDF

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Filed Under: Critical Judgment, Drug Shortages, Heresy, Lasix, NTG, Paramedicine 101, Physician Oversight, Research Tagged With: , , , ,

Do Drug Shortages Really Impact EMS? – Answer 1

Wed, 08 Sep 2010 18:39:51 -0400 by
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Here is part 1 of the details from the points I raised in commenting on the discussion of the drug shortages and the way these affect EMS. I already gave the short answers in Do Drug Shortages Really Impact EMS? – EMS Office Hours. These will be a bit longer, so I broke it up by answer. There are many points covered for a podcast that lasts less than 40 minutes. Do Drug Shortages Really Impact EMS?

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1. Do the drugs help patients?

I have recently written about why these drugs are inappropriate here, here, here, and here.

These drugs are based on either, or both, of 2 bad ideas.

First – Expired expert opinion. Opinion that is not supported by good research. When the research has been done, the research has not supported these treatments.

By expired, I do not mean that the expert has expired, but that the opinion has been kept in use long past any possible justification. If this were canned food in your cupboard, the can would be bulging at both ends from the disgusting growth on this very dead opinion.

Second – Not just expired expert opinion, but opinion that is not based on any research. There is the possibility that research will someday demonstrate that these treatments are effective, if anyone ever appropriately studies these ideas. It is also possible that the parts of the moon that have not been examined actually are made out of cheese. This is the morass of Class IIb level of evidence.

Class II: Conditions for which there is conflicting evidence and/or a divergence of opinion about the usefulness/efficacy of a procedure or treatment.

IIa. Weight of evidence/opinion is in favor of usefulness/efficacy

IIb. Usefulness/efficacy is less well established by evidence/opinion.[1]

There is no requirement for any evidence.

The highlighting is mine, but the wording is 100% ACC/AHA (American College of Cardiology/American Heart Association). The people who thought antiarrhythmics were the answer to everything, until research showed an antiarrhythmic fatality rate several times higher than placebo.[2]

Oopsy.

Perhaps I am putting too positive a spin on the Class II levels of evidence. Some of what is classified as IIa is not much different from IIb, because there is still the allowance for expert opinion. Any reading of this research should be preceded by the words, Wouldn’t it be nice if . . .

However, that is not the way to decide what chemicals to test on a patient.

Let’s be honest. That is all we are doing. We are testing chemicals and/or procedures on patients. We are not treating patients, because treatment implies some sort of concern for the patient. This is just a bunch of large scale never-to-be-published, uncontrolled, unregistered, unreasonable experiments on patients who are not informed of their guinea pig status.

I want to know the real risks and benefits of this treatment.

Wouldn’t it be nice if . . .

How far do we need to go to demonstrate that bad ideas really are bad ideas?

We need to demand that medical directors base their EMS protocols on research.

Why are medical directors ignoring what is best for their patients?

Why are medical directors ignoring what is best for our patients?

Why should we tolerate this ignorance?

I’m a doctor.

Wouldn’t it be nice if . . .

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Continued in –
Do Drug Shortages Really Impact EMS? – Answer 2
Do Drug Shortages Really Impact EMS? – Answer 3
Do Drug Shortages Really Impact EMS? – Answer 4

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Footnotes –

[1] Manual for ACC/AHA Guideline Writing Committees
Methodologies and Policies from the ACC/AHA Task Force on Practice Guidelines
Section II: Tools and Methods for Creating Guidelines
Step Six: Assign Classification of Recommendations and Level of Evidence
Free Full Text Article

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[2] C A S T and Narrative Fallacy
Rogue Medic
Article

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Filed Under: Critical Judgment, Drug Shortages, EMS Office Hours, Heresy, Physician Oversight, Research Tagged With: , , ,

How to Study Epinephrine in Cardiac Arrest

Fri, 30 Apr 2010 02:35:47 -0400 by
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No. This is not a post about a study that did everything the right way. I don’t even think there is any such study in progress. This is my description of what is necessary for a future study to be valid.

I have written a lot about epinephrine in cardiac arrest. So far there is no research to support the use of epinephrine, unless we believe that the surrogate endpoint of ROSC (Return Of Spontaneous Circulation) is important. Surrogate endpoints have a long history of leading people to make bad mistakes. I have already written about surrogate endpoints several times.[1]

Here is one explanation of the way surrogate endpoints are used:

From this unhappy rhythm – the beginning point.

We add a drug that we know does a great job of improving the surrogate endpoint and then we have this happy rhythm. The improved rhythm is the surrogate endpoint. It is a surrogate (substitute) for showing improved survival, because this does not require as many study participants.

The surrogate endpoint also led us to the rhythm below. The surrogate endpoint misled us.

Survival with good neurological function is the only meaningful end point. Once we had enough participants in a well controlled trial, we were able to find out that making the rhythm look better did not make the patient better.

The study drugs did a great job of making the rhythm look better. It looked like a great drug – A lifesaver! – until there was a study large enough to show a difference in survival.

When a study large enough to show a significant difference in survival was done, we could see that more than 3 times as many patients receiving the study drugs were dropping dead.

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In looking at epinephrine for cardiac arrest, we need to forget about surrogate endpoints. We’ve studied that to death. We need to look at survival.

The study has to be large enough to show a difference in survival.

The study needs to control for confounding variables as much as possible.

The study needs to be randomized and double-blinded.

The study needs to track from before the first resuscitation drug is given to hospital admission, at the very minimum.

The study really should look at the difference in outcome between the study drug and the placebo after the first drug is given.

While the rate of patients resuscitated before medication should be equal in the placebo and study arms, we should probably recognize that these are not patients who will be affected by epinephrine. These may also be the patients least likely to present as needing aggressive post-resuscitation care. It is an assumption, but it does seem reasonable that, more responsive to initial interventions means less low-circulation/no-circulation time in cardiac arrest and, we might expect, less intensive post-resuscitation care.

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What we want to know is the difference between the patients who do receive epinephrine and the patients who do not receive epinephrine, but would have received epinephrine if not in a study of epinephrine in cardiac arrest. These are the patients who do not receive epinephrine because of the study design, not because of responsiveness to earlier treatments. Nobody interacting with the medics should know which patient received which treatment.

We need some agreement on post-resuscitation care. I used to regularly present ACLS classes with this scenario of a patient just resuscitated. When someone would ask for vital signs, I would state that the blood pressure is 60 by palpation.

This presents them with an important treatment decision. This may be the most important treatment decision of this patient’s life.

How do we approach this patient?

1. A systolic pressure of less than 90. We must give fluids and dopamine.

2. We got a resuscitation. We’re going to Disney World. Maybe we’ll drop off the patient on the way.

3. The systolic pressure rose 60 points in the last minute. Maybe I should wait to see what happens in the next minute, and the minutes after the next minute, before making decisions about aggressive interventions that may discourage this patient from maintaining any pulse.

I think you will be able to guess what my approach is. I grew up with Disney movies on Sunday night. High Fives and high tail it to the park. 😉

We would need to have some sort of protocol to standardize post-resuscitation care, because I know a lot of people – doctors, nurses, and paramedics – who would already have dopamine running before the next blood pressure.

I think the research shows that therapeutic hypothermia works, so this would probably be a requirement for participation.

CPR should be standardized to whatever the next guidelines come up with before the beginning of the study. I hope that Dr. Ewy’s minimally interrupted, continuous compression CPR is what the AHA/ILCOR/ARC decide to adopt. (They did not. Ventilation is still viewed as important, even though there is not research to demonstrate that ventilations improve outcomes. We continue to mistakenly look at withholding an ineffective treatment as an intervention that needs to be supported by excellent evidence, rather than the actual treatment – ventilations, epinephrine, amiodarone, et cetera – as something that needs to be supported by excellent evidence.)

We need to look at subpopulations to see if epinephrine is effective in some groups, while not effective in other groups. This could explain why the overall effect is not impressive.

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There needs to be a randomization of placebo and epinephrine syringes with many different identification markings, such as individual numbers with no pattern. The reason for the variety in the markings is to make it almost impossible for the medics to figure out which are active drugs and which are placebos. Those running the study should also be prevented from knowing which patients are receiving the active drug – epinephrine. Or some other method of randomization and blinding that can be shown to be effective at blinding EMS.

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If this is done the right way, there should not be much doubt about what to do with epinephrine after the conclusion of the study. Either epinephrine is significantly better than placebo and belongs in resuscitation guidelines, or we only use epinephrine when specifically indicated – potentially reversible causes of cardiac arrest and for any subpopulation identified as having better survival after epinephrine.

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I am sure there are things I have not included, but this is what is needed. Either we find out what is best for patients, or we continue to give a treatment that is based on tradition and the short-term ability to bring back a pulse.

Maybe I am wrong. Maybe this is already being done.

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Footnotes:

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[1] C A S T and Narrative Fallacy
Rogue Medic
Article

Some other surrogate endpoint posts:

New Series of Rants Second follow up

C A S T and Narrative Fallacy comment from Shaggy

EMS EdUCast – Journal Club 2: Episode 43

The association between emergency medical services staffing patterns and out-of-hospital cardiac arrest survival

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Updated 12-06-10 at 13:49 and some wording changed for clarity. In other words, parts that didn’t make as much sense as I thought they did, when I originally wrote them.

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Filed Under: Critical Judgment, EMS EduCast, Epinephrine, Heresy, Research Tagged With:

Everyone knows what bogus treatments are – or do they?

Thu, 01 Apr 2010 20:43:36 -0400 by
Simon Singh won his appeal of the libel decision that is summarized in that quote –

Everyone knows what bogus treatments are. – High Court judge Mr Justice Eady paragraph 7 (12)[1]

Perhaps some explanation is in order.

One of the reasons I write this blog is that not enough people know what bogus treatments are, or how to determine what treatments are bogus. I do not limit myself to EMS (Emergency Medical Services) treatments.

Simon Singh wrote an article explaining about bogus treatment, but The BCA (British Chiropractic Association) cried libel. High Court judge Mr Justice Eady demonstrated his profound ignorance by finding in favor of the frauds. A bad time for science, but do not worry, gentle reader, the truth will come out.

Perhaps High Court judge Mr Justice Eady thought he would be remembered as Justice Potter Stewart is for (the highlighting is mine) –

under the First and Fourteenth Amendments, criminal laws in this area are constitutionally limited to hard-core pornography. [n2] I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description, and perhaps I could never succeed in intelligibly doing so. But I know it when I see it, and the motion picture involved in this case is not that.[2]

I agree with High Court judge Mr Justice Eady that there is little difference between bogus treatments and hard core pornography. However, High Court judge Mr Justice Eady makes it quite clear that he does not know what bogus treatments are.

The claim that Everyone knows what bogus treatments are, is itself bogus.

The way we determine what is bogus and what is not is by using scientific inquiry.

While anyone can make fantastic claims about a treatment, and a lot of bogus treatments have fantastic claims made about them, that is only a correlation. Penicillin had fantastic claims made about it. Penicillin did live up to some of those claims. Penicillin did not put an end to infectious disease, but it did have a dramatic effect death from infection. Penicillin, as with all treatments, has had problems. Penicillin has plenty of research to show when it is an appropriate treatment. Penicillin did not just rely on fantastic claims. Penicillin is still used, because of doctors putting aside the fantastic claims and looking at the research. That is real medicine.

How does High Court judge Mr Justice Eady know what a bogus treatment is?

They are not merely treatments which have proved less effective than they were at first thought to be, or which have been shown by the subsequent acquisition of more detailed scientific knowledge to be ineffective. Bogus treatments equate to quack remedies; that is to say they are dishonestly presented to a trusting and, in some respects perhaps, vulnerable public as having proven efficacy in the treatment of certain conditions or illnesses, when it is known that there is nothing to support such claims. – High Court judge Mr Justice Eady paragraph 7 (12)[1]

Allow me to rewrite that for High Court judge Mr Justice Eady.

Everyone knows what bogus treatments are after these treatments repeatedly fail to demonstrate superiority to placebo in valid scientific studies.

They are not merely treatments which have proved less effective than they were at first thought claimed to be, or which have been shown by the subsequent acquisition of more detailed scientific knowledge to be ineffective never been shown to be effective.

Bogus treatments equate to quack remedies; that is to say they are dishonestly presented to a trusting and, in some respects perhaps, vulnerable public as having proven efficacy in the treatment of certain conditions or illnesses, when it is known that there is nothing to support such claims. A perfect example is that, The British Chiropractic Association claims that their members can help treat children with colic, sleeping and feeding problems, frequent ear infections, asthma and prolonged crying, even though there is not a jot of evidence.[1] As Simon Singh stated in the alleged libelous article.

There have been some developments since the original libel complaint. One was the release by BCA of a plethora of evidence supporting the claims that chiropractic can successfully treat children with colic, sleeping and feeding problems, frequent ear infections, asthma and prolonged crying. The Lay Scientist addresses the 29 studies in a post that found the plethora to be less than a jot of evidence.[3] Many other bloggers did likewise.

Following this public humiliation of the BCA, and the suggestion that they should change the name to the Bogus Chiropractic Association, a separate group (McTimoney Chiropractic Association) sent an emergency letter to its members essentially telling them that the claims they have been making may land them in jail. It seems that they are beginning to understand that the research they have used as the basis for treatment is worthless. Actually much less than worthless, since it will cost them money, reputation, and possible jail time. They had to have this explained to them by bloggers more literate in research than any of these chiropractic doctors. I wish I could claim that I had been one of them, but I did not write much on the topic, and I did not review any of the research on my blog, since it was done so swiftly and completely elsewhere.

If you have a website, take it down NOW.[4]

REMOVE all the blue MCA patient information leaflets, or any patient information leaflets of your own that state you treat whiplash, colic or other childhood problems in your clinic or at any other site where they might be displayed with your contact details on them. DO NOT USE them until further notice. The MCA are working on an interim replacement leaflet which will be sent to you shortly.[4]

If you use business cards or other stationery using the ‘doctor’ title and it does not clearly state that you are a doctor of chiropractic or that you are not a registered medical practitioner, STOP USING THEM immediately.[4]

IF YOU DO NOT FOLLOW THIS ADVICE, YOU MAY BE AT RISK FROM PROSECUTION.[4]

Most importantly, this email and all correspondence from the MCA is confidential advice to MCA members alone, and should not be shared with anyone else.[4]

Yes, I have selected parts of this letter that are more incriminating than others. However, they are making this clear, they believe the way they have been advertising is illegal. They need to change things in order to abide by the law. In other words, they assert that Simon Singh was completely accurate in his article.

Here is the most ironic part –

Be wary of ‘mystery shopper’ phone calls and ‘drop ins’ to your practice, especially if they start asking about your care of children, or whiplash, or your evidence base for practice.[4]

Imagine if any professional organization told a group of its members, at least if they are real medical professionals, You do not know enough to answer questions from patients about the evidence supporting the treatments they use regularly.

In essence, this is what they are saying –

We screwed up. We need to make up another story.

Until further notice we advise you to –

Change the subject.

Make counter accusations.

Stonewall.

Without our advice, you will continue to break the law.

And don’t call yourself a doctor, let’s get real about the trade school you attended.

What did High Court judge Mr Justice Eady write?

Bogus treatments equate to quack remedies; that is to say they are dishonestly presented to a trusting and, in some respects perhaps, vulnerable public as having proven efficacy in the treatment of certain conditions or illnesses, when it is known that there is nothing to support such claims. – High Court judge Mr Justice Eady paragraph 7 (12)[1]

McTimoney Chiropractic Association seems to be making it quite clear that High Court judge Mr Justice Eady is describing the actions of McTimoney Chiropractic Association. They don’t like it, but they can’t charge him with libel, he is the libel judge defending chiropractic quackery. They may even need to see real doctors for treatment of their apoplexy.

Back to the ruling of the Court of Appeals.

What “evidence” signifies depends heavily on context. To a literalist, any primary fact – for example, that following chiropractic intervention a patient’s condition improved – may be evidence of a secondary fact, here that chiropractic works. To anyone (and not only a scientist) concerned with the establishment of dependable generalisations about cause and effect, such primary information is as worthless as evidence of the secondary fact as its converse would be. The same may equally well be true of data considerably more complex than in the facile example we have given: whether it is or not is what scientific opinion is there to debate. If in the course of the debate the view is expressed that there is not a jot of evidence for one deduction or another, the natural meaning is that there is no worthwhile or reliable evidence for it. That is as much a value judgment as a contrary viewpoint would be. – Court of Appeals paragraph 26[1]

It appears that not all judges are as easily or willfully fooled as High Court judge Mr Justice Eady.

If in the course of the debate the view is expressed that there is not a jot of evidence for one deduction or another, the natural meaning is that there is no worthwhile or reliable evidence for it.

It is now nearly two years since the publication of the offending article. It seems unlikely that anyone would dare repeat the opinions expressed by Dr Singh for fear of a writ. Accordingly this litigation has almost certainly had a chilling effect on public debate which might otherwise have assisted potential patients to make informed choices about the possible use of chiropractic. If so, quite apart from any public interest in issues of legal principle which arise in the present proceedings, the questions raised by Dr Singh, which have a direct resonance for patients, are unresolved. This would be a surprising consequence of laws designed to protect reputation. – Court of Appeals paragraph 11[1]

Accordingly this litigation has almost certainly had a chilling effect on public debate which might otherwise have assisted potential patients to make informed choices about the possible use of chiropractic.

When you hear someone claiming that a statement is libel (or slander) think about this.

Is the claim of libel an attempt to silence debate or to encourage healthy debate?

A more thorough review of the legal aspects can be found at Jack of Kent. He has a post about this, but promises to examine this decision in more depth over the weekend.[5]

A more thorough review of the scientific aspects can be found at The Guardian in an article by Dr. Ben Goldacre. He examines the history and concludes with this.

a ragged band of bloggers from all walks of life has, to my mind, done a better job of subjecting an entire industry’s claims to meaningful, public, scientific scrutiny than the media, the industry itself, and even its own regulator. [6]

Footnotes:

^ 1 British Chiropractic Association v Singh [2010] EWCA Civ 350 (01 April 2010)
England and Wales Court of Appeal (Civil Division) Decisions
Free Full Text of Decision

^ 2 Jacobellis v. Ohio (No. 11)
173 Ohio St. 22, 179 N.E.2d 777, reversed.
Concurring Opinion of Justice potter Stewart
Free Full Text with links to other sections of the decision

^ 3 A Review of The BCA’s Evidence for Chiropractic
The Lay Scientist
Post

^ 4 McTimoney Chiropractors told to take down their web sites
The Quackometer
A copy of the McTimoney Chiropractic Association letter is posted in full.
Post

^ 5 BCA v Singh: An Astonishingly Liberal Judgment
Jack of Kent
Post

^ 6 An intrepid, ragged band of bloggers
The Guardian
by Dr. Ben Goldacre
Article

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Filed Under: Critical Judgment, Heresy, Unicorn Medicine Tagged With: , ,

Journal Club 3: Episode 53

Sun, 28 Mar 2010 14:34:03 -0400 by

ResearchBlogging.org
Also posted over at Paramedicine 101 and at Research Blogging. Go check out the rest of the excellent material at both sites.

Of the two podcasts I had the opportunity to be on this week, this one is more to my liking, due to my desire to increase the use of research-based treatments. Having the lead author of one of the studies on the show was another positive. Greg Friese hosts Journal Club 3: Episode 53.

There is a much more thorough discussion of these papers on the podcast.

The papers covered are:

Resuscitation on television: realistic or ridiculous? A quantitative observational analysis of the portrayal of cardiopulmonary resuscitation in television medical drama.
Harris D, Willoughby H.
Resuscitation. 2009 Nov;80(11):1275-9. Epub 2009 Aug 20.
PMID: 19699021 [PubMed – indexed for MEDLINE].
Presented by Rob Theriault.

This study raises a lot of interesting questions about the way that people learn about making end of life decisions, what they anticipate the outcome of resuscitation will be, and even how medical professionals may respond to skills presented in TV medical dramas.[1]

Dismissing TV dramas as trivial ignores the effect that they may have on members of the audience, up to and including doctors.

The Canadian prehospital evidence-based protocols project: knowledge translation in emergency medical services care.
Jensen JL, Petrie DA, Travers AH; PEP Project Team.
Acad Emerg Med. 2009 Jul;16(7):668-73.
PMID: 19691810 [PubMed – indexed for MEDLINE].
Presented by Joe Clark.

This is a study that deserves several posts to cover, so I will not even start here. As with the other studies, this paper is discussed on the podcast.

My impression is that this resource is wonderful. If you know of a relevant paper that they do not cover on the site, send them a link to it. As with all of science, this will always be a work in progress, but that is certainly not a bad thing.

Canadian Prehospital Evidence Based Protocols.

Effectiveness of paramedic practitioners in attending 999 calls from elderly people in the community: cluster randomised controlled trial.
Mason S, Knowles E, Colwell B, Dixon S, Wardrope J, Gorringe R, Snooks H, Perrin J, Nicholl J.
BMJ. 2007 Nov 3;335(7626):919. Epub 2007 Oct 4.
PMID: 17916813 [PubMed – indexed for MEDLINE].
Presented by Bill Toon.

In the US, we have studies that show an inability of the medics (at least the medics in US studies) to be able to safely direct patients to alternative destinations, such as an appointment with a general practitioner. Is the basic EMS education difference, between the US and the UK, the reason?

This study does show that specially trained experienced paramedics can identify stable patients and safely direct these patients to more appropriate resources than the Emergency Department (Accident & Emergency in the UK).

This is an education program that appears to focus on critical judgment, rather than protocol adherence. If done the right way, this should be good for patients, and therefore good for EMS and hospitals.

The full text PDFs of the three papers discussed on the podcast are available for free (until the next EMS EduCast Journal Club) at the Journal Club page of the EMS Educast.

Special guests on the show are Joseph F. Clark, PhD of JosephFClark.com and Jan Jensen of the Canadian Prehospital Evidence Based Protocols.

Footnotes:

^ 1 Positioning prior to endotracheal intubation on a television medical drama: perhaps life mimics art.
Brindley PG, Needham C.
Resuscitation. 2009 May;80(5):604. Epub 2009 Mar 18. No abstract available.
PMID: 19297069 [PubMed – indexed for MEDLINE]

Inadequate positioning of the head and neck was especially prevalent prior to intubation attempts, and improving this was seen as a simple but important first step.

As part of ongoing nationwide efforts to ensure basic resuscitation skills5 we explored all potential causes for the inadequate positioning, and this included trainees’ prior experiences. Many trainees reported limited supervision or hands-on training. Remarkably, however, when asked how they had therefore learned, after “trial and error”, a surprising number answered that television medical dramas had been an important influence.

Of the remaining 22, none (0/22) achieved more than one, let alone all three, components of optimal airway positioning. In terms of individual components, the lower cervical-spine was flexed in 0/22, the atlanto-occipital joint extended in 1/22, and the ears level with the sternum in only 3/22 cases.

While few would suggest that medical dramas can be held responsible for physician performance, it has been previously suggested that they can significantly influence beliefs.6, 7

This does show that ignoring the effect of medical dramas has the potential to be harmful to patients.

Harris, D., & Willoughby, H. (2009). Resuscitation on television: Realistic or ridiculous? A quantitative observational analysis of the portrayal of cardiopulmonary resuscitation in television medical drama☆ Resuscitation, 80 (11), 1275-1279 DOI: 10.1016/j.resuscitation.2009.07.008

Jensen, J., Petrie, D., Travers, A., & , . (2009). The Canadian Prehospital Evidence-based Protocols Project: Knowledge Translation in Emergency Medical Services Care Academic Emergency Medicine, 16 (7), 668-673 DOI: 10.1111/j.1553-2712.2009.00440.x

Mason, S., Knowles, E., Colwell, B., Dixon, S., Wardrope, J., Gorringe, R., Snooks, H., Perrin, J., & Nicholl, J. (2007). Effectiveness of paramedic practitioners in attending 999 calls from elderly people in the community: cluster randomised controlled trial BMJ, 335 (7626), 919-919 DOI: 10.1136/bmj.39343.649097.55

Brindley, P., & Needham, C. (2009). Positioning prior to endotracheal intubation on a television medical drama: Perhaps life mimics art Resuscitation, 80 (5), 604-604 DOI: 10.1016/j.resuscitation.2009.02.007

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Filed Under: EMS EduCast, Heresy, Paramedicine 101, Research, Research Blogging Tagged With: , , ,

Correction on Intravenous drug administration during out-of-hospital cardiac arrest: a randomized trial.

Sun, 07 Mar 2010 20:08:55 -0500 by
ResearchBlogging.org

Also posted over at Paramedicine 101. Go check out the rest of what is there.

In Intravenous drug administration during out-of-hospital cardiac arrest: a randomized trial,[1], [2] I missed some important information. I think I expected more detail to be in the text, than in the charts and figures, so I did not read Figure 2 carefully enough. Regardless of the reason, I did miss some important information.

In response, Anonymous left this comment –

RM: I was doing some reading on this article and came across your commentary. I am unsure if you will even see this since your blog was posted a few months ago, but I just thought I would clear something up for you and anyone else who reads your commentary. You seem to have done an inadequate job of reading and understanding this article.

Yes, I did.

Specifically, you state that a major shortcoming of the study is that 10% of the no-IV group received IV medications. You actually go on make a joke about “falling on a IV” as being an unacceptable excuse.

Sometimes I think I am funnier than I actually am.

If you had read the article closely you would have noticed a perfectly adequate explanation for this, as well as the 18% of the IV med group who did not receive meds.

Yes. It is not hidden. It should not have required a close reading, but I did miss both of these.

The reason the no-IV did receive drugs was because of ROSC (Return Of Spontaneous Circulation) then subsequent new cardiac arrest (27), hospital admission (13), breach of protocol (5)…45/433=10%. I would argue that 5/433 (1%), is pretty good for a study of this magnitude.

I agree. However, if the breach of protocol had been 10%, that would have been ten times higher and reason for comment. Clearly the breach of protocol was not that high and my criticism was inappropriate.

Paramedics often make mistakes. Arrests are stressful. It seems unreasonable for you to criticize this study for 5 episodes. It would be difficult if not impossible for the researchers to have controlled that any better short of being in every ambulance. I hope this sheds a little light on the topic for you.

I agree. I was wrong. Thank you for correcting me.

On the other hand, I think that cardiac arrests should not be stressful. We spend so much time on teaching the use of medications, advanced airways, and IVs. We have no evidence that any of these lead to better survival. These unproven interventions are just more to distract EMS from what has been shown to work by good evidence. We create unnecessary stress.

What you pointed out only lends more support to conclusion of the study – that IV medications do not improve outcomes from cardiac arrest. There still is no evidence that routine use of IV medication does anything to improve survival from cardiac arrest. Without evidence to show improved survival, these treatments should only be considered experimental.

In the bizarre world of medical research in the US, these experimental treatments have become the standard of care. The lack of research cannot be overturned with anything less than the highest quality research. That research is more likely to be done outside of the US, because it is considered unethical to deprive US study participants of a standard of care, even though there is absolutely no evidence of improved survival with the standard IV medications in cardiac arrest.

Anyway, back to my errors. I made the same mistake with the protocol deviations in the IV arm of the study.

442 Randomized to intravenous administration group

418 (95% of 442) Included in primary analysis

24 (5% of 442) Excluded due to predefined exclusion criteria

17 (4% or 442) Cardiac arrest witnessed by ambulance crew

6 (1% or 442) Resuscitation not attempted

1 (<1% or 442) Traumatic etiology

344 (82% of the 418 Included in primary analysis) Intravenous drug administration established and administered as randomized

74 (18% of 418) Intravenous drug administration not established prior to end of resuscitation

42 (10% of 418) Restoration of spontaneous circulation before intravenous administration

12 (3% of 418) Inability to establish intravenous access

12 (3% of 418) Intravenous administration considered futile

8 (2% of 418) No explanation given

For the information already mentioned by Anonymous –

474 Randomized to no intravenous administration group

433 (91% of 474) Included in primary analysis

41 (9% of 474) Excluded due to predefined exclusion criteria

17 (4% of 474) Bystander physician ordered treatment

14 (3% of 474) Cardiac arrest witnessed by ambulance crew

5 (1% of 474) Resuscitation not attempted

4 (1% of 474) Traumatic etiology

1 Asthma-induced cardiac arrest

388 (90% of 433 Included in primary analysis) No intravenous drug administration established or administered as randomized

45 (10% of 433) Intravenous drug administration occurred

27 (6% of 433) Restoration of spontaneous circulation and new cardiac arrest

13 (3% of 433) Hospital admission

5 (1% of 433) Breach of protocol

I am a bit confused by the meaning of Hospital admission. Were these EMS responses to treat patients in hospitals? Elsewhere Hospital admission is used as a measurement of short term outcome – whether the patient survived to the hospital. Survival to the hospital is just a short term outcome that has led to the adoption of treatments which have later been shown to increase long term harm. therefore, these short term outcomes probably should be ignored, rather than highlighted.

For the IV group, there were 2% listed as no explanation given, but nothing specifically listed as protocol violations.

Rather than an IV/No IV approach, blinded randomization to use of a placebo syringe/active drug syringe should not be that much more difficult.

And we need to stop the ethicists from forcing experimental treatments on unsuspecting uninformed patients in the name of ethics.

Footnotes:

^ 1 Intravenous drug administration during out-of-hospital cardiac arrest: a randomized trial.
Rogue Medic
Article

^ 2 Intravenous drug administration during out-of-hospital cardiac arrest: a randomized trial.
Olasveengen TM, Sunde K, Brunborg C, Thowsen J, Steen PA, Wik L.
JAMA. 2009 Nov 25;302(20):2222-9.
PMID: 19934423 [PubMed – indexed for MEDLINE]

If you want to read the entire study, this link opens it in PDF.

Olasveengen TM, Sunde K, Brunborg C, Thowsen J, Steen PA, & Wik L (2009). Intravenous drug administration during out-of-hospital cardiac arrest: a randomized trial. JAMA : the journal of the American Medical Association, 302 (20), 2222-9 PMID: 19934423

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Filed Under: Heresy, Paramedicine 101, Research Blogging Tagged With: , ,

Influence of Sex on the Out-of-hospital Management of Chest Pain – Part I

Thu, 11 Feb 2010 00:15:39 -0500 by
ResearchBlogging.org

Also posted at Research Blogging. Go read some of the other research there.

Why Part I? Because there is a lot to write about in this study. While the authors mean well, they end up demonstrating two things.

1. How not to do a study.

2. How a medical director can endanger patients by lowering standards to meet the perceived abilities of the available medics in an EMS (Emergency Medical Services) system.

Let’s start at the beginning. In spite of the title, this has nothing to do with the Influence of Sex on the Out-of-hospital Management of Chest Pain. It would be more appropriately titled – Are Women Treated Differently When Classified By EMS Dispatch As Having Chest Pain. Not as catchy a title, but this is not about intercourse-induced chest pain. Other problems with the title should be easy to spot as you read along.

We get all the way to the second paragraph, when the research problems scream Look at me!
 

Of the 16 million patients per year who are cared for and transported to the hospital by emergency medical services (EMS), 8% have a chief complaint of undifferentiated chest pain, possibly suggesting acute coronary syndrome (ACS).16 [1]

 

Reference number 16 is an interesting paper, but it is a study of ambulance diversion by the ED (Emergency Department). It is not a study of the incidence of potentially cardiac symptoms among those transported by EMS. From the abstract –
 

Study objective: We describe emergency department (ED) visits in which the patient arrived by ambulance and estimate the frequency of and reasons for ambulance diversion. Using information on volume of transports and probabilities of being in diversion status, we estimate the number of patients for whom ED care was delayed because of diversion practices.[2]

 

The authors did break patients down by Principal reason for visit, but why use a paper that is examining ambulance diversion as a reference?

I assume that the answer is that they saw a huge amount of data and figured more is better. It may not have occurred to the authors that patient’s presentation to EMS may not be the same as the patient’s presentation to the ED.

While 7.9% of EMS patients did have a Principal reason for visit of “Chest pain and related symptoms (not referable to body system)”, that may have absolutely nothing to do with EMS management of Suspected Acute Coronary Syndrome. Acute Coronary Syndrome (ACS) is currently the preferred terminology a possible heart attack. One of the reasons for using this terminology is that Chest Pain is a typical male symptom of a heart attack. Women often present with other symptoms, such as tiredness for a number of days, difficulty breathing, weakness, nausea, and many other atypical symptoms. In Pennsylvania, there are statewide protocols. These protocols do not include a Chest Pain protocol, but the protocols do include one for Suspected Acute Coronary Syndrome.

Look at some of the other categories of Principal reason for visit.

* 5.7% Shortness of breath.

* 2.9% General weakness.

* 2.9% Labored or difficult breathing (dyspnea).

* 2.3% Fainting (syncope).

These are patients with potential acute coronary syndromes. Even more so for women, who are less likely to present with the male chest pain syndrome of crushing substernal pressure radiating to the neck, jaw, and/or arm.

Add these up, since they appear to be listed by only the primary Principal reason for visit, so there should be no overlap. All categories do add up to 100%.

The total for non-Chest Pain potential ACS is 13.8%.

Then you add in those with an actual Principal reason for visit of chest pain (7.9%) and you have 21.7%. They have excluded over 60% of patients with presentations that might be cardiac.

This is probably an insignificant difference and should be ignored. At least, that is what I would conclude from the way the authors treat this information. The Principal reason for visit was limited to 10 categories, of which half could be cardiac. The rest are lumped into All other reasons. Maybe nausea, vomiting, tiredness, arm pain, jaw pain, malaise, difficulty walking, et cetera. Many of these might be assessed as possible ACS, but the authors of the diversion study only specified the top 10 categories. This leaves 58.3% of patients.

How many of those would present with possible ACS?

Not wanting to leave well enough alone with this diversion study, they came up with some more inaccurate information.
 

Of all U.S. out-of-hospital (OOH) patients, nearly half are women.16 [1]

 

This is referencing the same study, so I do not have to look far to find their data –

* Female        8,763 patients, which works out to 54.2% Of all U.S. out-of-hospital (OOH) patients. Those arriving by ambulance were 14.4% of the total number of ED patients.

* Male           7,402 patients, which works out to 45.8% Of all U.S. out-of-hospital (OOH) patients. Those arriving by ambulance were 14.0% of the total number of ED patients.

Perhaps the authors need to be a bit more clear on what they mean by nearly half. Even if they were correct in concluding that 54.% is nearly half, what would that matter. What is important is whether women make up a significant proportion of those patients patients presenting with possible ACS.

I think that the title of this paper and two paragraphs are enough for Part I. I address some of the research on gender differences in ACS symptoms, as well as the rest of the paper, in Part II.

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Edited at 15:30 on 5/16/2018 to update links, format, and to make a correction. I had incorrectly listed second citation from footnote 1 as being from footnote 2.

–

Footnotes:

–

[1] Influence of sex on the out-of-hospital management of chest pain.
Meisel ZF, Armstrong K, Mechem CC, Shofer FS, Peacock N, Facenda K, Pollack CV.
Acad Emerg Med. 2010 Jan;17(1):80-7. doi: 10.1111/j.1553-2712.2009.00618.x.
PMID: 20078440

Free Full Text from Academic Emergency Medicine

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[2] Analysis of ambulance transports and diversions among US emergency departments.
Burt CW, McCaig LF, Valverde RH.
Ann Emerg Med. 2006 Apr;47(4):317-26. Epub 2006 Feb 17.
PMID: 16546615

–

Meisel, Z., Armstrong, K., Crawford Mechem, C., Shofer, F., Peacock, N., Facenda, K., & Pollack, C. (2010). Influence of Sex on the Out-of-hospital Management of Chest Pain Academic Emergency Medicine, 17 (1), 80-87 DOI: 10.1111/j.1553-2712.2009.00618.x

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Filed Under: Assessment, Critical Judgment, Heresy, Research Blogging Tagged With: , , , ,
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