Tuesday, 23 November 2021

Dexamethasone in hospitalized patients with COVID-19


Prior to the publication of this study, there was quite a lot of debate about the efficacy of dexamethasone for hospitalized patients with COVID. 

But not now…

The RECOVERY trial was designed to quickly look at many potential treatments for COVID. A whopping 176 NHS organizations in the UK were involved and with no shortage of patients to enroll.

Hospitalized patients with COVID were randomized to get either 6mg of dexamethasone daily for 10 days or usual care alone.

Primary outcome was all cause mortality at 28 days. There were lots of prespecified secondary outcomes.

6425 patients were recruited from March to June 2020. Overall, 22.9% of patients in the dexamethasone group died vs. 25.7% in the usual care arm. Absolute difference of 2.8% for a number needed to treat (NNT) of 36.

But the benefit seemed to be best in the sickest patients that were ventilated; NNT 8. There was a trend towards harm in the healthier group not requiring oxygen.

There are some limitations to this study, the biggest being our care of COVID has changed since it was conducted, care was not standardized, and this was an unvaccinated cohort. Nevertheless, it was generally well performed and (for now) it is considered practice changing.

Dexamethasone is no “magic bullet” but another piece of the puzzle that might provide some benefit to those sick enough to be hospitalized with COVID. However, no therapies have come even close to the benefits we see with vaccination.

Get ‘em all vaccinated!

 

Covering:

The RECOVERY Collaborative Group, Dexamethasone in Hospitalized Patients with COVID-19. N Engl J Med 2021;384:693-704. [link to full text article]

 

 

 

Tuesday, 19 October 2021

MRI of cervical spine in trauma: A retrospective single-centre audit of patient outcomes


In patients with a normal cervical spine CT but persistent tenderness or neurology, how often is a subsequent MRI abnormal? And what happens afterwards? Here's an answer from Gelong...

(Spoiler alert... the real question should be, "does MRI find occult injury that results in genuine improvements in patient-oriented outcomes? Or does it cause harm from overdiagnosis?")

These authors from a single centre, looked retrospectively at a cohort of trauma patients that had both a negative cervical spine CT and a subsequent MRI. (Adult patients had to be alert and <72 hours between the studies.)

Results?

228 patients were included.

Of the 181 patients that had the MRI for persistent tenderness, 35 (20% or one-in-five) had an abnormal MRI. Of those, 14 were treated with a rigid collar and no patients underwent surgery.

Of the 47 patients that had the MRI for neurological findings, 11 (23%) had an abnormal MRI. Four patients were managed with collars. Two patients required surgery and the manuscript described their presentation & hospital course. Their neurologic issues were not subtle.

The authors appropriately conclude that the MRI is of “questionable” utility in those without neurology.

But could the MRI be even worse? Could it identify injuries that would heal just fine had we never found them only to subject patients to weeks of unnecessary immobilisation, discomfort, and potential harm? Unfortunately, this was not really addressed in this study.

With technology advances, MRI will only get more sensitive at finding “abnormalities." In addition, MRI will become more readily available. We need to have some serious discussions; just because we can, should we? 

 

Covering:

Foster G, Russel B, Hibble B, et al. Magnetic resonance imaging cervical spine in trauma: A retrospective single-centre audit of patient outcomes. Emerg Med Aus. 2021 Sep 3.doi: 10.1111/1742-6723.13842. [link to article]

Sunday, 17 October 2021

The effectiveness of intradermal sterile water injection for low back pain in the ED: A prospective, randomized controlled trial


Intradermal water injection to alleviate low back pain?

Believe it or not, water injection has been around for many years, especially in the delivery suite. There are some proposed mechanisms as to why or how it might work.

But can water injection work in the Emergency Department?

These authors from a single center in Turkey, randomized low back pain patients who all got IV NSAIDS to either intradermal water injection or nothing else.

Inclusion criteria were adults 18-65 years old with a VAS pain score of >4. They excluded trauma, chronic back pain, those that had pain medications prior to arrival, diabetes, or BMI >30.

Outcomes were reduction of pain at 10, 20, 30 minutes and 24 hours. They also looked at patient satisfaction, need for rescue medication, etc.

Results?

112 patients enrolled and the water worked FANTASTIC! Everything they could measure was better.

Hallelujah… we have a miracle!

Unfortunately, there are some serious problems with this study.

The manuscript is awful and serves as a red flag as to the professionalism and conduct of these researchers. I would have genuinely believed that they used Google Translate and submitted a draft without changes. But there are words in the manuscript that don’t even exist on Google!

Regardless of the sloppy manuscript, there are serious methodological issues that likely render the conclusions invalid.

It was not blinded.

Of course, patients were not blinded, but nor were the clinicians in the study who also collected the outcome measures. This could have resulted in substantial subject and observer bias.

And of course, there is the placebo effect…

(But to be fair to these researchers, what is the placebo for water? Or how can you perform sham water injection? I don’t know.)

In short summary, this terribly presented paper’s findings are very likely due to bias and placebo effect.

But is it unethical to use undisclosed placebo? Holy hallelujah can of worms…

 

Covering:

Tekin E, Gur A, Bayraktar M, et al. The effectiveness of intradermal sterile water injection for low back pain in the emergency department: A prospective, randomized controlled study. Am J Emerg Med 2021;42:103-109. [link to article]

Friday, 15 October 2021

Risk stratification of patients admitted to hospital with covid-19- the 4C Mortality Score


This group of researchers from the UK sought to develop and validate a pragmatic risk score to predict mortality in patients admitted to hospital with COVID.

This prospective cohort study was performed at 260 hospitals in the UK in early 2020.

35,463 patients were included in the derivation phase and 22,361 in the internal validation. The mortality was about 30% of these admitted patients… yikes!

They used a complicated three stage model building process and used some regression analysis, machine learning and lots of other things probably best understood by those with a PhD in biostatistics.

In the end, they came up with 8 variables to predict mortality. They included age, sex, number of comorbidities, respiratory rate, oxygen saturations, GCS, urea, and CRP.

Although they intended for this score to be quite simple, nobody is going to memorize the components and how to add things up. Fortunately, mdcalc.com can do it for you.

The researchers also compared their score to 15 others in existence and thought theirs to be the best.

So, use this score if you like.

Some would argue that this score is already outdated. In the last year we have learned a lot more about COVID. Treatments have changed. And biggest limitation of all, most of the data was derived from an unvaccinated cohort.

Either way, this score has some utility. And it’s just like all risk stratification scores out there.

Yes… (wait for it)sicker patients do worse.

Or more specifically; sicker patients with worse manifestation of disease, who are older with more comorbid illness, have worse x-rays & blood tests, and lack of response to initial treatment do worse.

I use that score for everything. But for some reason, I can't find it on Mdcalc.

 

Covering:

Knight SR, Ho A, Pius R, et al. Risk stratification of patients admitted to hospital with covid-19 using the ISARIC WHO Clinical Characterisation Protocol: development and validation of the 4C Mortality Score. BMJ 2020;370:m3339. [Link to full text article]

Point-of-Care hip ultrasound leads to expedited results in ED patients with suspected septic arthritis


The title tells it all; if you do something yourself, it happens faster. Case closed...

But perhaps there is a little more we can learn from this paper.

These authors from beautiful Charlottesville, Virginia looked retrospectively at 62 patients who got an ultrasound for possible septic arthritis in their ED.

They compared the group that had the ultrasound done by ED doctors (POCUS) vs. those done in radiology. No surprise the POCUS group had the study done faster; about 1 hour vs. 3 hours.

They also looked at time to arthrocentesis which was also faster when performed by the ED doctor; about 3 hours vs. 10 hours.

Of course, this study was only from a single center, it was not randomized, and they had very small numbers. Only 10 arthrocentesis were performed by the ED doctors over 3 years. It can make no genuine claims about safety.

Hmmmm…

As ED doctors, we are very happy at tapping various joints. I’ve done tons of knees. And some shoulders, elbows, wrists, ankles and toes. But I’ve never aspirated a hip.

For some reason the hip has been taboo. Perhaps it is due to the less common nature and the higher incidence in the pediatric population. It's a deeper joint and more difficult to physically confirm the presence of an effusion. Furthermore, historic blind aspiration techniques were outside our realm.

This is not the first study looking at POCUS to guide hip arthrocentesis in the ED and we are now supported by a growing literature base.

EP’s are clearly owning ultrasound guided needle-based procedures. Perhaps hip arthrocentesis will eventually fall to the responsibility of the Emergency Physician. 

Hmmmm….

 

Covering:

Thom C, Ahmed A, Kongkatong M, et al. Point-of-care hip ultrasound leads to expedited results in emergency department patients with suspected septic arthritis. JACEP Open 2020;1:512-20. [link to full text article]

 

  

Thursday, 2 September 2021

Utilization of Prophylactic Antibiotics After Nasal Packing for Epistaxis


When I trained, I was told I needed to prescribe prophylactic antibiotics after I placed nasal packing. It was thought this reduced the potential for toxic shock syndrome or sinusitis. Is this recommendation evidence based?

Hmmmm…

This single ED in Manhattan retrospectively reviewed 275 cases of anterior nasal packing and determined the rates of antibiotics given and evidence of benefit.

Most patients that got non-absorbable packs (Merocel, RapidRhino) got antibiotics. Those with absorbable packs (Surgicel, Gelfoam) did not.  Although this aspect of the study is robust, it is hardly important… I just don’t care.

I want to know how many patients got benefit from antibiotics.

Out of the 275 cases, there was one episode of sinusitis in each group. Looks like it doesn’t matter?

But there is a fatal flaw.

They didn’t really look for outcomes.

Only 40% of the patients had documented follow up! In addition, this would have been poor quality retrospective data.

If you don’t look for something, you will not find it. Interesting that this study got published.

Probably the best thing to come out of this “study” is their review of the literature.  In a nutshell, there is moderate evidence to show that antibiotics are not needed after nasal packing.

Good enough for me.

 

Covering:

Hu L, Gordon SA, Swaminathan A, et al. Utilization of Prophylactic Antibiotics after Nasal Packing for Epistaxis. J Emerg Med. 2021;60:140-149. [link to article]

 

Elevated blood pressures are common in the ED, but are they important?


No.

You can stop reading now if you want…

This was an electronic medical record review of 30,278 adults treated and released from the University of Alberta ED in 2016.

They identified those that had elevated BP’s at triage and cross-referenced them with multiple data bases to see if they developed cardiovascular events by 2 years(Databases included hospital EDIS, Pyxis, Pharmaceutical Information Network, administrative data holdings, National Ambulatory Care Reporting systems, outpatient billing claims etc.)

Of the 30,278 that were treated and released, about half had elevated BP’s at triage. 70% had no prior history of hypertension and eventually about a quarter of those subsequently received a diagnosis of chronic hypertension.

After adjusting for confounders, high BP at triage was not associated with adverse cardiovascular outcomes within 2 years of the ED visit.

I’m willing to believe this is true… but there are many methodologic limitations.

Don’t be mesmerized by the huge number of patients… this does not guarantee quality. Nor do large numbers reduce bias.

I’m concerned about a potential “garbage in & garbage out” phenomenon. The veracity of this study is predicated on the quality of the information in many large databases. (For example, a large database in the USA shows the rate of virgin births at 0.5%)

There were a lot of other issues; retrospective design, residual confounding, use of triage BP’s, lack of follow up, possible non-differential misclassification, etc.

So, are elevated BP’s in the ED important?

I still say no, but not necessarily due to this study. Heck, at least hypertension is better than hypotension. 

 

Covering:

McAlister FA, Youngson E, Rowe B. Elevated Blood Pressures are Common in the Emergency Department but Are they Important? A Retrospective Cohrt Study of 30,278 Adults. Ann Emerg Med. 2021;77:425-432. [link to article]

  

Accuracy of OMI ECG findings vs traditional STEMI criteria for diagnosis of acute coronary occlusion MI... the OMI manifesto?


I’ve heard of many manifestos.

There’s the Communist Manifesto, the US Declaration of Independence, the Unabomber Manifesto and now we’ve got the OMI Manifesto.

(Ok… it’s not a freakin manifesto. But good to know about anyway.)

The charge is being led by the master sensei Dr Stephen Smith (of ECG blog fame) and his student Dr Pendell Meyers. They’ve published quite a few articles looking at additional ECG criteria to identify patients that may benefit from emergent reperfusion of an acute coronary occlusion.

They hypothesized that blinded interpretation of their new OMI criteria would be more accurate than the traditional STEMI criteria.

OMI criteria?

OMI (occlusion MI) is basically STEMI criteria plus some STEMI equivalents including:

Subtle STE not meeting criteria, hyperacute T waves, reciprocal ST depression and/or negative hyperacute T waves, STD worrisome for posterior MI, suspected new Q waves, terminal QRS distortion, positive Sgarbossa criteria, any inferior STE with SZTD or T wave inversion in aVL

Without going into any details of the study, they thought the OMI criteria were great. Sensitivity went up from about 40% to 85%. Specificity remained around 90%.

Unfortunately, the manuscript as published in the open access journal IJC Heart & Vasculature is quite difficult to follow. It is poorly presented and would have benefited from substantial revision. Either way, you don’t need to read it… the message is rather simple and has a degree of face validity (albeit with many limitations).

What are we to conclude?

If you are an expert at ECG interpretation, you can probably identify more patients with acute coronary occlusion MI by using OMI criteria (which most of us are already doing to some extent). Whether additional patients genuinely benefit from an aggressive intervention is officially not known.

 

Covering:

Meyers P, Bracey A, Lee D, et al. Accuracy of OMI ECG findings versus STEMI criteria for diagnosis of acute coronary occlusion myocardial infarction. IJC Heart & Vasc. 2021:33; 100767 [link to full text article]

Monday, 5 July 2021

Effectiveness and safety of small-bore chest tubes (20 Fr) for chest trauma patients

The optimal chest tube size for the relief of traumatic haemo/pneumothorax is not known. Traditionally, garden hoses up to 36 to 40 Fr in size have been recommended. The outer diameter of one of these tubes is up to 13mm… ouch!

A more recent observational study caused ATLS/EMST to recommend tubes a bit small at 28-32 Fr. This is still something I don’t think I would want hanging out of my chest.

Not based on any high-quality evidence, these authors from Kobe, Japan decided that 20 Fr or an 8 Fr pigtail was good enough. After some time, they decided to describe their results. Yes… this was their methods.

Results?

Over 5 years, they put in 107 chest tubes. About 90% were 20 Fr and the rest were pigtail catheters. The mean Injury Severity Scale (ISS) was 17.8.

There were 8 (7.8%) tube related complications, and none were due to tube obstruction. There were 4 retained haemothoraxes and 4 unresolved pneuomothoraxes.

The authors conclude that it might be reasonable to safely manage chest trauma patients with small-bore chest tubes.

This retrospective observational study is of low-quality evidence and should not change practice. But it may provide some clinical equipoise to support a proper randomized trial. This should definitively answer the research question.

After all these years, I’m quite surprised a large RCT has not been conducted. It strikes me that it should be feasible and ethical to perform. These are usually the major challenges in conducting experimental trials. A review of clinicaltrials.gov shows only one small study out of Egypt but it is not yet recruiting.

What are we waiting for? (There must be something I’m missing…Bueller... Bueller ?)



Covering:

Maezawa T, Yanai M, Young Huh J, et al. Effectiveness and safety of small-bore tube thoracostomy (<20 Fr) for chest trauma patients: A retrospective observational study. Am J Emerg Med. 2020;38:2658-2660. [link to article]

 

A randomized, noninferiority trial of two doses of IV ketamine for analgesia in the ED


This study aimed to determine if a low dose of ketamine (0.15mg/kg) was just as good (or bad) as a higher dose (0.3mg/kg).

This single ED in Chicago conducted a double-blind RCT that included adult patients with acute pain (flank, abdo, back, musculoskeletal or headache) and had a >5 on their initial NRS.

There were several exclusion criteria including patients that had chronic pain or currently taking opioids. This is arguably the patient population who would likely be best targeted for ketamine… but I digress.

Ketamine was given as initial therapy without co-administration of any other analgesics. Yikes!

Oh… and the ketamine was given as a slow IV infusion over 15 minutes (to decrease side effects and increase nursing hassle).

The primary outcome, NRS, was measured at 30 minutes. They also measured adverse events with the Richmond Agitation Sedation Scale (RASS) the Side Effect Rating Scale of Dissociative Anaesthetics (SERSDA). (Ketamine is so special, it even comes with its own measure tool for side effects.)

Results?

98 patients were enrolled and there was no statistical difference in the primary outcome nor side effects at 30 minutes. The authors conclude a lower dose is fine.

I disagree.

As a surrogate of patient satisfaction, the authors asked the patients, “would you take this medication again for similar pain?An astounding number said no; 25% vs. 40% in the low and high dose respectively. This is arguably the most important outcome of this study… patients really didn’t like this stuff (even when given slowly to minimize side effects).

Let’s face it, we would never use ketamine this way. It is not first line therapy. Would never use it in isolation. We would target our patient population differently. And logistically, we probably would not give an infusion.

So, what can we conclude? Don’t use ketamine this way.

Generally speaking, the hype and enthusiasm for subdissociative ketamine for pain is ridiculous. Yes, it has its place. But bang-for-buck, it’s a dirty drug; it doesn’t work that well and comes with many side effects.


Covering:

Lovett S, Reed T, Riggs R, et al. A randomized, noninferiority, controlled trial of two doses of intravenous subdissociative ketamine for analgesia in the emergency department. Acad Emerg Med. 2021;00:1-8. DOI:10.1111/acem.14200 [link to article]

Thursday, 1 July 2021

The ED-AWARENESS Study: A prospective cohort study of awareness with paralysis in patients intubated in the ED


Evidently, awareness with paralysis rather bad. Some studies indicate it is associated with PTSD, depression, and other psychological sequelae. I'll take their word for it...

But how often do patients have awareness after intubation in the emergency department?

This single centre prospective cohort study of 383 patients was conducted in Washington University in St. Louis.

After eventual extubation, patients were questioned about their experiences. Three independent reviewers independently adjudicated whether there was awareness with paralysis.

Results?

2.6% (10/383) of patients reported awareness. Exposure to rocuronium in the ED was found to be an associated risk factor.

There are many challenges to this type of study. There is no blood test for awareness. Measurement of the outcome was self reported. As such, it relies on the accurate memories of patients after major illness and complicated hospital stays.

Nevertheless, some of the descriptions on Table 2 of the manuscript are worrisome. One such case of a patient getting fiberoptic nasotracheal intubation after angioedema is below:

“I came to the ED because my tongue was swollen. I remember them putting the breathing tube down, but I could not move. I remember the breathing tube actually going in and being panicked. It was terrible and traumatic. I was panicking inside…”

This paper is not high-quality science, but it does have a simple message. A small number of ED patients may have awareness after intubation. Longer acting paralytics may not provide the clinicians a visual cue that patients are waking up.

Others might argue that small rates of awareness are the price of business in trying to save lives in the ED. Do we really want to heavily sedate that hypotensive trauma patient? Hmmm…

 

Covering:

Pappal RD, Roberts BW, Mohr NM, et al. The ED-AWARENESS Study: A Prospective Observational Cohort Study of Awareness With Paralysis in Mechanically Ventilated Patients Admitted From the Emergency Department. Ann Emerg Med. 2021;775:32-544. [link to article]

A double blind RCT of IV chlorpromazine vs prochlorperazine for the treatment of acute migraine in the ED


This single centre study out of the ED at Austin Health, enrolled patients with migraine to either 12.mg IV chlorpromazine (Largactil/Thorazine) vs 12.5mg IV prochorperazine (Stemetil/Compazine).

The primary outcome was a reduction in pain at 60 minutes as reported on a 11 point (0-10) Numerical Rating Scale (NRS). They also recorded some secondary outcomes and safety measures.

Results?

65 patients were included.

It doesn't take a statistical genius to understand this study was only powered to find a large treatment difference. So, it is no surprise they didn’t find one in the primary nor secondary outcomes.

The only statistical difference noted was side effects. Chlorpromazine had worse hypotension and syncope.

What does this study add to our knowledge?

Not much.

It was an elegant study design but woefully underpowered to adequately answer the study question. It makes me wonder why they bothered. Such small numbers can only find huge differences (which rarely exist in medicine) and often cannot get rid of baseline difference in study population and confounding; precisely the reason for conducting a randomized trial.


Covering:

Hodgson SE, Harding AM, Bourke EM, et al. A prospective, randomized, double-blind trial of intravenous chlorpromazine for the treatment of acute migraine in adults presenting to the emergency department. Headache. 2021;61:603-11. [link to article]

Tuesday, 27 April 2021

Outpatient Treatment of Low-Risk Pulmonary Embolism in the Era of DOACs: A Systematic Review


Is it safe to send someone home with a low-risk PE on a rivaroxaban or apixaban?

This systematic review identified 12 studies (four RCT’s and 8 prospective cohort studies) that might provide us the answer. Of course, the foundation author is Jeff Kline.

Patients were mostly categorized as “low risk” by using the HESTIA, PESI, or sPESI scores. (I personally like the HESTIA score as it has face validity and seems to send a lot of patients home.)

1,814 patients were included in this systematic review and they pretty much all did fine. Rates of mortality, recurrent VTE, and major bleeding was all below 1%.


“There was a single instance of PE related mortality within 90 days among the 1,814 outpatients in high quality studies.”


The authors state they have three main findings.

First, there are few controlled studies. But to answer the question, I don’t think we need a control arm. A well conducted cohort study should be fine.

Second, there were low rates of major adverse outcomes.

Third, there was no difference in patient outcomes with warfarin or with DOACs. For what it’s worth, 97% of the DOACs chosen were rivaroxaban.

It appears that the preponderance of evidence shows that sending low-risk patients home with oral rivaroxaban is safe.

However, there is a currently a large study by Jeff Kline enrolling patients in 33 hospitals in the USA to look at a protocol for outpatient management of VTE. So of course, our thoughts could all change.

 

Covering:

Maughan B, Frueh L, McDonagh MS, et al. Outpatient Treatment of Low-risk Pulmonary Embolism in the Era of Direct Oral Anticoagulants: A Systematic Review. Acad Emerg Med 2021;28:226-239. [Link to article]

Monday, 26 April 2021

Apnoeic oxygenation was associated with decreased desaturation rates during RSI in multiple Australian and New Zealand ED’s


The Australian New Zealand ED airway registry (ANZEDAR) includes 43 ED’s that prospectively submit data on patients they intubate. It has provided a wealth of information on how we manage airways.

This study looked at patients who got apnoeic oxygenation (ApOx) during RSI vs. those that did not. (ApOx was defined as patients getting up to 15L of oxygen via a nasal cannula.) They excluded patients intubated during cardiac arrest and those that got BVM or NIV during the apnoeic period.

The primary outcome was rates of desaturation to <93%.

Results

1669 (66%) patients got ApOx and 850 (33%) did not. Desaturation occurred in 10% of the ApOx group vs. 13% in the other group.

ApOx rules!!!

Maybe… maybe not…

This was not a randomized trial. As such, there could have been confounding factors or that led to the differences observed. (But to be fair, I would imagine that doctor would have been more likely to provide ApOx in those patients that they were worried might desaturate. Therefore, making the ApOx group look potentially worse. But perhaps I’m wrong…)

This was a study of registry data. Unfortunately, this data is often of poor quality. It’s possible we may have a “garbage in, garbage out” phenomenon. Intubation is often an anxiety provoking procedure where doctors get task focused. They may have not really been aware of how low the saturations dropped. Ideally, one would get the data from a research assistant who is tasked to collect accurate data at the time.

Desaturation is not really a patient-oriented outcome. Transient hypoxemia probably causes no harm in most patients. Ideally, we would look at more important outcomes involving real patient morbidity and mortality. But good luck powering such a study!

If ApOx doesn’t really change any important patient outcomes than arguably it may be one extra step that distracts us from getting the job done. In times of high stress, we need to keep our processes as simple as possible.

The debate continues…

 

Covering:

Perera A, Alkhouri H, Fogg T, et al. Apnoeic oxygenation was associated with decreased desaturation rates during rapid sequence intubation in multiple Australian and New Zealand emergency departments. Emerg Med J 2021;38:118-124. [Link to article]

Sunday, 25 April 2021

The Use of Tranexamic Acid to Reduce the Need for Nasal Packing in Epistaxis (NoPAC): RCT


We all know tranexamic acid (TXA) is good for everything. It’s great for trauma, all kinds of bleeding and heck, tastes great on Weet Bix. But a lot of this enthusiasm is now being challenged by hard science.

These researchers from the UK randomized 496 patients with epistaxis (after failure of nasal compression and topical vasoconstrictor) to topical tranexamic acid or placebo.

Trial treatment was with cotton wool dental roll either soaked in 200mg tranexamic acid or sterile water. The dental roll was left in for 10 minutes and could be repeated a second time if the bleeding continued.

The primary outcome was the need for anterior nasal packing.

Results?

The mean age was about 70 and two thirds were on anticoagulants.

In the end, the rates of anterior nasal packing were about the same in both groups at 40%.

The authors conclude the that tranexamic acid is no better than placebo.

But I’m not so sure this is going to change practice to those who are tranexamic acid afficionados.

The inclusion of mostly elderly patients on anticoagulants could have diluted the results to the null hypothesis. These are a hard group to treat and, in my experience, often get nasal packing. And remember, the patients enrolled in this study had already failed compression and vasoconstrictors.

So, perhaps TXA will work better in a different population.

Many would argue that TXA is cheap and very unlikely to cause harm. But so are bedside anti-epistaxis incantations. Either one of them is possibly a waste of time and distracting from performing other measures.

Perhaps save TXA for the Weet Bix? Hmmmm….

 

Covering

Reuben A, Appelboam A, Stevens K, et al. The Use of Tranexamic Acid to Reduce the Need for Nasal Pcking in Epistaxis (NoPAC): Randomized Controlled Trial. Ann Emerg Med. 2021 Feb 18;S0196-0644(20)31461-X [Link to article]

 

 

 

Diagnostic Accuracy of the HINTS Exam in an Emergency Department: A Retrospective Chart Review


The HINTS exam for evaluation of patients with acute vestibular syndrome (AVS) has been all the rage over the past decade. Originally described in 2009, it reported phenomenal accuracy at differentiating peripheral from central causes of vertigo. However, the performance of the test has mostly been validated by neurologists and otolaryngologist.

To qualify for a HINTS exam, patients must have AVS characterized by continuous dizziness and ongoing in the ED, nystagmus, and gait unsteadiness.

This retrospective chart review looked at how often a HINTS exam was appropriately performed and the sensitivity & specificity of the test at this single ED in Ontario. The authors point out that doctors did not get any specific training on the HINTS exam prior to this review.

A total of 2,309 patients presented with a primary complaint of vertigo or dizziness. Almost 20% got a HINTS exam! However almost all (96.9%) of them were performed inappropriately as it was not clinically indicated. In addition, many patients got both a Dix-Hallpike test and a HINTS exam… which should never happen as they are “intended in mutually exclusive patient populations.” 

In the end, the sensitivity & specificity of the test as performed was terrible.

What are we to conclude?

At this single ED, the HINTS exam performed poorly in untrained doctors who did the exam on the wrong patients.

They conclude that “additional training of emergency physicians may be required.” This is quite an understatement.

Of course, this study is far from perfect, but it serves as a cautionary tale.

This is not the only study suggesting a problem. A systematic review and metanalysis in 2020 concluded that “the HINTS exam, when used in isolation by emergency physicians has not been shown to be sufficiently accurate to rule out a stroke in those presenting with AVS.”

I do not think the HINTS exam is overly simple. Nor did I believe there are enough cases of vestibular stroke for an average emergency physician to develop and maintain proficiency with the exam. But perhaps I’m wrong… there are some very clever doctors who disagree with me.

Until such time we get further evidence, we should not be giddy over the HINTS exam.

 (** Addendum 28/4/2021: Please see comment section for feedback on my summary from Dr Peter Johns. He is a Canadian Emergency physician and vertigo guru. He wrote the book on vertigo... literally wrote the chapter in Tintinalli)

Covering

Dmitriew C, Regis A, Bodunde O, et al. Diagnostic Accuracy of the HINTS Exam in an Emergency Department: A Retrospective Chart Review. Acad Emerg Med 2021;28:387-393. [link to free full text]

 

 

Sunday, 21 February 2021

Compression Therapy to Prevent Recurrent Cellulitis of the Leg… way to go Bruce!


We’ve all seen them…

Those big red chronic oedematous legs that we diagnose as cellulitis. We start IV antibiotics and admit. But those same legs come back to the ED again and again…

Hummm... should we be doing something to prevent recurrent cellulitis in oedematous legs?

These investigators from the Public Hospital Bruce, Canberra, conducted a single centre non-blinded RCT of patients with chronic oedema of the leg and recurrent cellulitis. Participants were randomised to leg compression therapy vs. control.

The primary outcome was recurrence of cellulitis as diagnosed by GP’s or hospital physicians and confirmed by trial assessors. There were a bunch of secondary outcomes including measuring leg volume with the use of a perometer (huh?), quality of life, adherence to intervention etc.

Shortly after starting the trial, lymphoedema therapists who were aware of the group assignments noticed a potential large treatment effect and brought it to the attention of the Human Research Ethics Committee (HREC). Stopping rules were added to the study protocol. As expected, the trial was stopped early for efficacy.

In the end, 84 patients were enrolled with 23 episodes of recurrent cellulitis. There were 6 (15%) patients with cellulitis in the compression group and 17 (40%) in the control arm.

Wow… an absolute reduction of 25% or NNT of 4. This is crazy efficacy.

(Just in case you were curious, the perometer showed a between group difference of -240ml in leg volume over time.)

Critics of this trial could justifiably point out that it was really small, stopped early, and conducted at single centre.  But perhaps the biggest limitation was the diagnosis of recurrent cellulitis is subjective and it was adjudicated by those who were unblinded- potentially leading to bias.

Either way, these results are very compelling, in line with expert opinion and should be practice changing. As ED doctors, we don’t usually focus on preventative medicine. But this intervention will have much more effect than those countless tetanus immunisations we give away.

Looks like it’s time to get on the compression train.


Covering:

Compression Therapy to Prevent Recurrent Cellulitis of the Leg. N Engl J Med. 2020;383:630-9. [link to article]

Saturday, 20 February 2021

Short-Term Topical Tetracaine is Highly Efficacious for the Treatment of Pain Caused by Corneal Abrasions: A double-blind RCT


It seems to me that these researchers asked the wrong question. Most of us know that numbing up a corneal abrasion relieves pain. But the big question has always been is it safe to send patients home with topical anaesthetic. For decades, ophthalmologist have been telling us it is dangerous.  But lately, this dogma has been challenged with better quality research.

So if they didn't ask the right questions, then why was this study conducted and published in our peak emergency medicine journal?

It turns out we have never proven the efficacy of topical anaesthetics for outpatient treatment of simple corneal abrasions with an RCT. Go figure...

But, now we have.

This well conducted RCT out of a single ED in Oklahoma (yeeeehaaaaaaa!) randomised 111 patients to 2ml’s of tetracaine drops vs placebo to take home. The primary outcome was the overall NRS pain score at a 24-hour and 48-hour ED follow-up.

As expected, the tetracaine worked marvellously. Pain score was 1/10 in the tetracaine group and 8/10 in the placebo group. This is a huge difference with lots of pretty p values. The placebo group also gulped down more Vicodin than the those given tetracaine (don’t get me started…)

Unfortunately, we cannot make claims about safety with so few trial participants. A much larger study will be needed to find less common side effects. But the original studies that suggested harm are old and poor quality. It seems that the current best evidence suggests topical anaesthetics are probably safe and definitely effective for simple corneal abrasions.

But don’t be surprised if your local ophthalmologists disagree… it's hard to teach an old dog(ma) new tricks. 

 

Covering:

Shipman S, Painter K, Keuchel M, et al. Short-Term Tetracaine is Highly Efficacious for the Treatment of Pain Caused by Corneal Abrasions: A Double-Blind, Randomized Clinical Trial. Ann Emerg Med. 2020 Oct 27;S0196-0644(20)30739-3.    doi: 10.1016/j.annemergmed.2020.08.036 [link to article]

 

 

Thursday, 18 February 2021

Early Rhythm-Control Therapy in Patients with Atrial Fibrillation

Rate vs. rhythm control of atrial fibrillation has been a perennial question.


These investigators sough to determine if patients with “early atrial fibrillation” (<1 year since diagnosis) and cardiovascular conditions had better outcomes with rhythm control.

The was a behemoth study and worthy of publication in the NEJM.

2789 patients in 135 centres in 11 different countries in Europe were randomised to either rhythm control (antiarrhythmic drugs, ablation, & cardioversion) vs. usual care (mostly rate control but occasionally rhythm control to manage AF related symptoms.)

One primary outcome was a composite of death from cardiovascular cause, hospitalisation for heart failure and/or ACS. The other primary outcome was nights spent in hospital. There were lots of secondary and safety outcomes.

After a median 5 year per patient follow up time, the trial was stopped early due to efficacy at the 3rd interim analysis. There was an absolute decrease of 1.1 events per 100 person years for the first primary outcome. This may not seem like much of a treatment effect, but there are a lot of people out there with AF.

No study is perfect, and this one has some limitations. There were reasonably narrow inclusion criteria which limit generalisability. It probably excluded most symptomatic patients as they would not have been candidates to be randomised to “usual care.” In the manuscript, there is an entire column of author conflicts of interest- in small font no less! Cardiologist love to cosy up to industry….

Either way, this study will change the guidelines. And in speaking with my local electrophysiologist, this study has already changed practice. Cardiologists are pushing suitable patients with new AF towards a rhythm control strategy with antiarrhythmics and more ablations are being performed.

Of course, emergency physicians are not likely to prescribe antiarrhymics and certainly won’t do ablations (unless you want a friendly visit from a regulatory body). But it is good for us to know the overall strategy and we will be asked to be more aggressive with early rhythm control.


Covering:

Kirchhof P, Camm AJ, Goette A, et al. Early Rhythm-Control Therapy in Patients with Atrial Fibrillation. N Engl J Med. 2020;383:1305-16. [link to article]

Testicular Workup for Ischemia and Suspected Torsion in Pediatric Patients and Resource Utilisation: Everybody do the TWIST?

 


The TWIST score is a "validated" clinical decision instrument to aid in the diagnosis of acute testicular torsion.

TWIST sore?

Yes, I’ve never heard of it either… and I will probably forget about it very soon.

The TWIST score (0-7) is calculated by the presence of testicular swelling (2 points), hard testes (2 points), nausea/vomiting (1 point), high riding testes (1 point), and absent cremasteric reflex (1 point). Based on the score, patients can be stratified into high, intermediate, or low risk. I’ll spare you further details…

These authors sought to apply the TWIST score to a group of patients by performing a retrospective medical record review. They were looking at potentially decreasing formal ultrasound use, decreasing ED length of stay and ischemic time. (Methods for their chart review are absent however…)

Results?

77 patients were identified by ICD-10 codes. All 9 high risk patients had torsion. And it was absent in the 57 low risk patients. The authors claim the score could have reduced the need for ultrasound 75% of the time and reduced ischemia time.

Sounds great, but there are major problems with this study.

Retrospectively collected data is usually poor quality. The authors assumed data not recorded indicated absence of findings. Of course, this is nuts (sorry).

Regardless of prior studies, I don’t believe the TWIST score has face validity. The most important features in diagnosis of torsion are the appropriate age (usually adolescent) and the history. Sudden severe pain with vomiting and potentially a high-riding testicle is all you need. These patients should not be getting ultrasounds… just an immediate referral to the appropriate surgeon. A hard & swollen testicle is very common in orchitis and I can’t believe it wound be discriminatory. 

Of course, a clinical decision instrument should improve upon what we do already. These scores must be compared to clinician gestalt before being adopted. Otherwise we don’t know if they will underperform and cause harm.

Regardless of what Cubby Checker says, please don’t do the TWIST.

 

Covering:

Roberts CE, Ricks WA, Roy JD, et al. Testicular Workup for Ischemia and Suspected Torsion in Pediatric Patients and Resourse Utilization. J Surg Res. 2021;257:406-411. [link to article]