Articles of the month (January 2016)

Welcome to another edition of the First1oEM articles of the month – a collection of my favorite reads from the emergency medicine literature.

Location, location, location

Drennan IR, Strum RP, Byers A et al. Out-of-hospital cardiac arrest in high-rise buildings: delays to patient care and effect on survival. Canadian Medical Association Journal. 2016. [article]

This was a retrospective study looking at a cardiac arrest registry. They decided to look at the floor that you lived on to see if it impacted your survival from cardiac arrest (with the primary analysis looking above or below the 3rd floor). They found that living on higher floors was associated with an increased likelihood of death. In the raw numbers, 4.2% of patients living below the 3rd floor survived, compared to only 2.6% of those living on or above the 3rd floor (p=0.002). Survival above floor 16 was only 0.9%, and no one living above the 25th floor survived. The theory is that higher floors mean longer delays to EMS arrival, and therefore the ever important chest compression and defibrillation.

Bottom line: Choose your home wisely


 What’s the best antibiotic to bring on your trip to Las Vegas?

Geisler WM, Uniyal A, Lee JY. Azithromycin versus Doxycycline for Urogenital Chlamydia trachomatis Infection. The New England journal of medicine. 373(26):2512-21. 2015. PMID: 26699167

This is a randomized, controlled non-inferiority trial comparing azithromycin (1 gram PO once) to doxycycline (100mg PO BID for 7 days) in 587 adolescents with chlamydia infections. For the primary outcome of treatment failure at 28 days, there were no treatment failures in the doxycycline group as compared to 5 (3.2% 95%CI 0.4-7.4%) in the azithromycin group. Based on their assumptions, they could not establish the noninferiority of azithromycin in this group, although I imagine the result will vary greatly depending on local resistance patterns.

Bottom line: I will continue using doxycycline as my first line agent


 The Quixotic quest for the chest pain decision rule

Greenslade JH, Parsonage W, Than M. A Clinical Decision Rule to Identify Emergency Department Patients at Low Risk for Acute Coronary Syndrome Who Do Not Need Objective Coronary Artery Disease Testing: The No Objective Testing Rule. Annals of emergency medicine. 2015. PMID: 26363570

We would all love a good rule to use to send chest pain patients home. This is a secondary analysis of 2 prior prospective ED trials including a total of 2396 chest pain patients. They derive 3 different rules that are supposed to tell you which patients don’t need further testing after biomarkers and ECGs. (Of course, if you have listened to me in the past, you will know that stress testing is not helpful in our low risk chest pain patients.) I am not going to go into the rules themselves, because I think the study is too flawed to be helpful. Incorporation bias is the major downfall of this study. Classic cardiac risk factors are a large component of these rules, but previous research has consistently shown that having classic cardiac risk factors does not help predict whether a patient’s chest pain is ACS in the emergency department. So how could those risk factors possibly help in a decision rule? It’s because the definition of ACS included unstable angina and revascularization, both of which are subjective outcomes determined by the cardiologist, and the cardiologists had access to the risk factor information. A patient with 5 risk factors is more likely to be cathed, but that doesn’t mean the cath was necessary. Similarly, a patient with more risk factors is more likely to be given the diagnosis of unstable angina. The risk factors didn’t predict the diagnosis of ACS, they were the cause of it.

Bottom line: It is unlikely that we will find easy decision tools for chest pain patients, but for the time being we should be happy that most patients are so low risk that they should be sent home without stress testing.


 How prepared are you to run a neonatal resuscitation?

Yamada NK, Yaeger KA, Halamek LP. Analysis and classification of errors made by teams during neonatal resuscitation. Resuscitation. 96:109-13. 2015. [pubmed]

I like the idea here: these authors videotaped a total of 250 real neonatal resuscitations and reviewed the tape to determine how well the neonatal resuscitation algorithm was followed. Continuous quality improvement in our most stressful resuscitations makes sense. These authors report that 23% of the actions observed were errors as compared to the published algorithm. However, I don’t think the errors were truly important errors. The most common error was failure to have a cap to place on the child’s head – is that really essential in the first minutes of resuscitation of an apneic neonate? There were some important errors reported, though, with half of the 12 intubation attempts lasting longer than 30 seconds. Although I don’t think this study really demonstrates it, neonatal resuscitations are stressful and rapid paced, making errors probable. Mental practice and simulation are great tools to help prevent these errors, in my very biased opinion.

Bottom line: Quality improvement in your most stressful resuscitations is a good idea. 

If you want to review the newest NRP guidelines, you can see my post here.


Best treatment for pediatric gastro? Prevention

Soares-Weiser K, Maclehose H, Bergman H. Vaccines for preventing rotavirus diarrhoea: vaccines in use. The Cochrane database of systematic reviews. 11:CD008521. 2012. PMID: 23152260

This is a Cochrane systematic review of two different vaccines (monovalent versus pentavalent) for rotavirus. They identified 29 RCTs covering 101,671 infants for the monovalent vaccine and 12 RCTs covering 84,592 infants for the pentavalent vaccine. Unfortunately, most studies use the relatively non-sensical “rotavirus specific diarrhea” as an endpoint, but it definitely seems to be decreased (RR 0.33 95% CI 0.21-0.50 for the monovalent). All cause diarrhea was also decreased in the trials that looked at it, with an NNT of about 40 for any diarrhea and 100 to prevent a hospitalization. There was no change in mortality. They did not document an increase in adverse reactions, but efficacy studies often under report harms.

Bottom line: The rotavirus vaccine prevents serious diarrhea – maybe that’s an easier sell than the measles?


 Overtreatment and anticoagulation for atrial fibrillation

Hsu JC, Chan PS, Tang F, Maddox TM, Marcus GM. Oral Anticoagulant Prescription in Patients With Atrial Fibrillation and a Low Risk of Thromboembolism: Insights From the NCDR PINNACLE Registry. JAMA internal medicine. 175(6):1062-5. 2015. PMID: 25867280

With the rise of the new, expensive anticoagulants, we are beginning to see a push to get these agents started for atrial fibrillation patients in the emergency department, ignoring the tiny daily risk of stroke and the importance for long term monitoring that we cannot provide. This is a registry based study. Out of a total of about 360,000 atrial fibrillation patients in the study, 11,000 had a score of 0 on two major stroke scales. However, 25% of this extremely low risk population was on blood thinner contrary to current guidelines.

Bottom line: We over treat patients. For everything. Remember that studies are generally the best possible scenario for medications, and that results in the real world will be worse as we expand treatment to patients who would not have been included in the studies. (If you want to watch this happen in real time, just watch interventional treatment for stroke over the next few years.)


Zika

Fauci AS, Morens DM. Zika Virus in the Americas – Yet Another Arbovirus Threat. The New England journal of medicine. 2016. PMID: 26761185 [free full text]

This is a basic review of the Zika virus that is currently causing a significant pandemic through Central and South America, and has potentially been linked to a significant number of birth defects (microcephaly) in Brazil. Zika is another mosquito borne virus without a specific treatment (like Dengue or Chikungunya). The symptoms are described as a milder version of Dengue fever, with fever, myalgias, eye pain, and maculopapular rash. Treatment is supportive.

Bottom line: Another emerging illness to be aware of in the returned traveller.

The CDC has issued a travel advisory advising pregnant women to postpone travel to areas in which Zika transmission is occurring.


Can you really multitask?

Skaugset LM, Farrell S, Carney M. Can You Multitask? Evidence and Limitations of Task Switching and Multitasking in Emergency Medicine. Annals of emergency medicine. 2015. PMID: 26585046

Emergency physicians are masters of multitasking – or so we think. This review explains that most of what we think of as multitasking is really rapidly switching between tasks, and even if you are good at it, this task switching slows you down and results in error. Unfortunately, the solution promoted in most other fields – limiting interruptions – just isn’t feasible in emergency medicine. Some suggestions this review makes to help: prioritize tasks according to acuity, recognize when interruptions can be delayed or redirected, practice skills so they become automatic (and don’t add to cognitive load), and use mental frameworks or external brains to limit cognitive work. Of course, optimizing your departmental workflow to limit interruptions, especially at critical times, is also important.

Bottom line: There is no such thing as multitasking, just rapid task-switching.


 Should we add TXA to the water supply?

Fox H, Hunter F. BET 1: Intravenous tranexamic acid in the treatment of acute epistaxis. Emergency medicine journal : EMJ. 32(12):969-70. 2015. PMID: 26598634

This is another one of those situations that we have to make decisions in the absence of any real evidence. The authors of this review were unable to find any studies to answer their specific question about the use of IV TXA in acute epistaxis. However, they do note that there are a few studies that show benefit of oral TXA in epistaxis as well as the study of topical TXA that I have previously discussed in this newsletter. Furthermore, the use of intravenous TXA in elective sinus surgery seems to limit blood loss, and we all know about the evidence for IV TXA in trauma. So there is no direct evidence, but plenty of reasons we might guess it could help.

Bottom line: I have never used IV TXA for epistaxis, but use it topically all the time. You can bet if I have a patient with severe epistaxis, I will give it a shot.


 Much like TXA, I love skin glue

Bugden S, Shean K, Scott M. Skin Glue Reduces the Failure Rate of Emergency Department-Inserted Peripheral Intravenous Catheters: A Randomized Controlled Trial. Annals of emergency medicine. 2015. PMID: 26747220

Tape and tegaderm has always seemed like a rather ineloquent method of securing IVs to me. In this non-blinded RCT of 380 peripheral IVs, they compared standard tegaderm and tape to skin glue (1 drop at the skin insertion site and one under the hub – this can be seen in this video.) For the primary outcome of IV failure (infection, phlebitis, occlusion, or dislodgement) at 48 hours, the skin glue was better (17% failure vs 27%, absolute difference 10% 95%CI 2-18%). The study was underpowered to assess the components of the composite outcome, but most of the failures were dislodgement. I don’t follow people for 48 hours – but a 27% failure rate with usual care seems high to me. Also, skin glue is likely more expensive. However, an NNT of 10 to avoid another IV stick would probably be attractive to many patients.

Bottom line: Skin glue is an option for securing PIVs – maybe difficult ones you really care about?


 I love ultrasound for looking at things, but for breaking up clots?

Piazza G, Hohlfelder B, Jaff MR. A Prospective, Single-Arm, Multicenter Trial of Ultrasound-Facilitated, Catheter-Directed, Low-Dose Fibrinolysis for Acute Massive and Submassive Pulmonary Embolism: The SEATTLE II Study. JACC. Cardiovascular interventions. 8(10):1382-92. 2015. PMID: 26315743

This is a large prospective study, but I won’t get too much into the details because their primary outcomes were a bunch of surrogate markers rather than patient important outcomes. Why included it then? They used a novel device that uses ultrasound to try to break up the PE, and then gave tPA at the very slow rate of 1mg/hr. So far the lytics for submassive PE trials have shown some promise, but aren’t convincing. Alternate methods (non-bolus) of giving the medication might be the thing that tip the balance in favour of lytics. But mostly I wanted to include this article to bring up two excellent blog posts written by Josh Farkas about ultrasound guided thrombolysis and controlled thrombolysis of submassive PE.

Bottom line: My guess is that we will find that lytics are beneficial in submassive PE over the coming years, once we find the correct subset of patients and the best dose. (This is a big departure for me, because I am much more used to saying that things won’t work. That is almost always the safer bet.)


 Ondansetron and the dreaded QT

Moffett PM, Cartwright L, Grossart EA, O’Keefe D, Kang CS. Intravenous Ondansetron and the QT Interval in Adult Emergency Department Patients: An Observational Study. Academic emergency medicine : official journal of the Society for Academic Emergency Medicine. 23(1):102-5. 2016. [pubmed]

Droperidol, possibly the most useful medication I have never had the opportunity to use, was taken away because of what it could do to the QT interval, right around the time when ondansetron was coming to market. Then, as ondansetron was coming off patent, we found out that it prolonged the QT just like droperidol did. OK, I will take off my tin foil hat to write the rest of this. This is a prospective observational trial of 22 adult patients receiving ondansetron at a single hospital. They did ECGs at baseline and every 2 minutes for 20 minutes. The QT did lengthen by 20 msec (95% CI 12-26 msec), but this is almost certainly clinically insignificant. There were no adverse events.

Bottom line: Yes, ondansetron will prolong the QT. No, it won’t be a problem. (Maybe avoid it if the patient overdosed on methadone, lithium, and haldol and tells you he has a family history of congenital long QT syndrome.)


 But little Johnny just aint right

Nishijima DK, Holmes JF, Dayan PS, Kuppermann N. Association of a Guardian’s Report of a Child Acting Abnormally With Traumatic Brain Injury After Minor Blunt Head Trauma. JAMA pediatrics. 169(12):1141-7. 2015. PMID: 26502172

I’ve included papers on the low risk of significant head injuries in children with isolated vomiting and isolated loss of consciousness before. This time we will look at whether parental concern that their child is acting abnormally, in isolation, is indicative of blood in the brain. This is another secondary analysis of the PECARN database. Out of 43,399 children in the original study, only 1297 were reported as acting abnormally. Of those, 411 (32%) had abnormal behaviour as their only finding. Only 1 child of these 411 had a clinically significant injury (0.2% 95% CI 0-1.3%). Of the smaller subset who had CTs performed, 4 out of 185 (2.2%) had any sign of traumatic brain injury. So injuries were rare, even when the parents report the child is not behaving normally.

Bottom line: Once again, you have to evaluate the entire patient, not just single variables. Observation is probably a better test than CT.


 How good is the ECG for hyperkalemia?

Montague BT, Ouellette JR, Buller GK. Retrospective review of the frequency of ECG changes in hyperkalemia. Clinical journal of the American Society of Nephrology : CJASN. 3(2):324-30. 2008. PMID: 18235147 [free full text]

Remember memorizing the classic progression of ECG changes in hyperkalemia: peaked Ts, prolonged PR, flatted Ps, wide QRS, then the deadly sine wave? Well, forget it. This is a chart review that looks at the ECGs of 90 hyperkalemic patients. (This is actually a reasonable topic for chart review, given that both the potassium level and the ECG are likely to be objective and easily identified on the chart.) Only half of the patients had any ECG signs of hyperkalemia, and only 18% met their strict criteria (which meant peaked Ts that were documented to resolve as the potassium decreased.) Although the ECG was insensitive for hyperkalemia, that might not be the important question. I don’t care as much about the number of the potassium, but whether it is affecting the heart – and the ECG might be a better marker of cardiac outcomes, but we don’t know from this study.

Bottom line: The ECG is not sensitive for hyperkalemia.


 A guideline that say something sensical? I must be dreaming

Kearon C, Akl EA, Ornelas J et al. Antithrombotic Therapy for VTE Disease: CHEST Guideline. Chest. 2016. [free full text]

This is a new guideline from the American College of Chest Physicians covering antithrombotic therapy for VTE. The recommendation to know about: “For subsegmental PE and no proximal DVT, we suggest clinical surveillance over anticoagulation with a low risk of recurrent VTE (Grade 2C).” That’s right – they are suggesting NOT treating certain PEs! They also recognize the high false positive rate of CTPA, which I have discussed here before. When is a subsegmental PE likely to be a true positive? “We suggest that a diagnosis of subsegmental PE is more likely to be correct (i.e. a true-positive) if: (1) the CT pulmonary angiogram (CTPA) is of high quality with good opacification of the distal pulmonary arteries; (2) there are multiple intraluminal defects; (3) defects involve more proximal sub-segmental arteries (i.e. are larger); (4) defects are seen on more than one image; (5) defects are surrounded by contrast rather than appearing to be adherent to the pulmonary artery; (6) defects are seen on more than one projection; (7) patients are symptomatic, as opposed to PE being an incidental finding; (8) there is a high clinical pre-test probability for PE; and D-Dimer level is elevated, particularly if the increase is marked and otherwise unexplained.” The best way to avoid this dilemma all together is still to avoid ordering CTs in low risk patients.

Bottom line: Not all PEs are really PEs. Not all PEs require treatment.


 Speaking of which

Nielsen HK, Husted SE, Krusell LR. Anticoagulant therapy in deep venous thrombosis. A randomized controlled study. Thrombosis research. 73(3-4):215-26. 1994. PMID: pubmed

I may have included this one before. Its really the only RCT of anticoagulation for VTE that exists as far as I know. This is a prospective, randomized trial of 90 patients with proven, symptomatic DVTs comparing anticoagulation (heparin followed by warfarin) with an NSAID (phenylbutazone). All the patients had VQ studies performed, both initially and for follow up. About half of the patients had PEs (asymptomatically). There was no difference between the groups with regards to regression of DVT, recurrent DVT, or PE up to 60 days. In terms of mortality, there was one death in the anticoagulation group and none in the NSAID group. The only difference was that the anticoagulation group had an 8% rate of bleeding complications while they report no adverse events from the NSAID. Now this is a small and imperfect study – but quite amazingly, it’s the only real study of anticoagulation for VTE, and it’s negative!

Bottom line: In the only RCT of anticoagulation in DVTs (half of whom had PEs), there was no difference between using an anticoagulant or an NSAID. I know which I would prefer.


 You thought diagnostics was difficult? How about pain caused by analgesics?

Tabner A, Johnson G. Codeine: An Under-Recognized and Easily Treated Cause of Acute Abdominal Pain. The American journal of emergency medicine. 33(12):1847.e1-2. 2015. PMID: 25983269

I have no idea what to do with this one. They present 2 case reports of patients with abdominal pain in whom the ultimate diagnosis was sphincter of Oddi spasm secondary to codeine use. Both patients’ pain resolved rapidly with naloxone (400mcg), which is not one of my usual analgesics. But how should we use this information? I imagine that you could do a lot of harm trying to treat abdominal pain with naloxone. This is definitely an interesting diagnosis – and one that I have never seen, or at least recognized.

Bottom line: Maybe one more reason that codeine should not be used


 Back pain? Do we really have to talk about back pain? Ugh

Friedman BW, Dym AA, Davitt M. Naproxen With Cyclobenzaprine, Oxycodone/Acetaminophen, or Placebo for Treating Acute Low Back Pain: A Randomized Clinical Trial. JAMA. 314(15):1572-80. 2015. PMID: 26501533

It’s sort of frustrating that trial after trial comes out telling us nothing really works for low back pain. Obviously we need to do something for our patients. This is a randomized, double-blind, placebo controlled trial comparing naproxen plus placebo to naproxen plus cyclobenzaprine and to naproxen plus oxycodone and acetaminophen in adults with acute non-traumatic lumbar back pain. For the primary outcome of a scale measuring pain and function, there was no difference between the groups. There were more adverse effects in the cyclobenzaprine and oxydodone/acetaminophen groups. The biggest weakness of this study was that there was relatively poor compliance with all treatment regimens, but that makes it more like real life.

Bottom line: Naproxen monotherapy is probably better. Adding cyclobenzaprine or oxycodone/acetaminophen just increases adverse effects.


 Sir, you have a severe antibiotipenia – we need to start an infusion, STAT

The BLISS trial: Abdul-Aziz MH, Sulaiman H, Mat-Nor MB. Beta-Lactam Infusion in Severe Sepsis (BLISS): a prospective, two-centre, open-labelled randomised controlled trial of continuous versus intermittent beta-lactam infusion in critically ill patients with severe sepsis. Intensive care medicine. 2016. PMID: 26754759

This wasn’t even on my radar: should we be giving antibiotics (specifically beta-lactams) as a continuous infusion? I know, we all heard about time dependent versus dose dependent antibiotics in medical school, but I honestly thought that was useless pharmacological drivel, because the studies I have seen so far have indicated that dosing regimen doesn’t matter much when we are giving antibiotics. (Maybe because we are giving so many antibiotics to people who really don’t need them?) Anyhow, on to the study: this was a prospective, randomized, open-label study of 140 adult ICU patients with severe sepsis being treated with cefepime, meropenem, or piperacillin/tazobactam. They were randomized to either receive their antibiotics as a continuous infusion, or by the usual intermittent dosing. The primary outcome was clinical cure, and was lower in the continuous group (56% vs 34%; absolute difference 22% 95%CI 10-40%, p=0.011). Unfortunately, I’m not sure that is the most important outcome, and the study wasn’t powered for mortality, so there was no significant mortality difference despite the numbers being better in the continuous group.

Bottom line: Continuous administration of beta-lactam antibiotics is interesting, and definitely warrants further study focusing on mortality differences


 Want to see how quickly I can contradict myself?

Dulhunty JM, Roberts JA, Davis JS. A Multicenter Randomized Trial of Continuous versus Intermittent β-Lactam Infusion in Severe Sepsis. American journal of respiratory and critical care medicine. 192(11):1298-305. 2015. PMID: 26200166

Hold your horses. The previous study was open-label, but there is another, larger study that was double-blinded. This is a double-blind, double-dummy multi-center randomized controlled trial of 432 ICU patients with severe sepsis being treated with meropenem, ticarcillin-clavulanate, or piperacillin-tazobactam, again comparing continuous versus intermittent dosing. For the primary outcome, ICU free days alive at day 28, there was no significant difference between the groups (18 vs 20 day, p=0.38). 90 day mortality was also the same, 26% in the continuous group vs 28% with intermittent antibiotics (p=0.67). So was the previous study just an example of the bias that can occur with open-label studies, or might there be a small but real difference that these studies were just under-powered to detect?

Bottom line: This will require a massive trial to answer definitively. For now, intermittent dosing is just so much easier that it should probably remain the preferred method of antibiotic administration.


Cheesy Joke of the Month

Why did the scarecrow get an an award?

He was outstanding in his field


 

#FOAMed of the month

We vastly overestimate the benefits of many of the medications that we tell our patients are essential. As a result, you can hear many of the elderly coming well before you see them from the rattle of all the pills. A large percentage of emergency department visits are from medication side-effects, but most of these are misdiagnosed. So although this tool was designed more for family physicians, I think it probably has a role in emergency medicine as well

Medstopper: http://medstopper.com/

This is a tool developed by some very intelligent Canadian doctors (including the team behind another amazing FOAMed resource: The Best Science Medicine podcast) to help clinicians and patients make decisions about reducing or stopping medications. The thing I miss most about family medicine was the ‘drugectomy’: it was astounding how many patients would feel so much better just because we stopped a few of their less necessary or unnecessary medications.

Management of life-threatening hyperkalemia

A brief guide to the immediate management of severe hyperkalemia in emergency medicine and critical care

Case

An 82 year old man with a history of end stage renal disease, hypertension, coronary artery disease, and prior admissions for hyperkalemia is brought in by EMS with a history a 3 days of nausea, diarrhea, and fatigue, culminating in a witnessed collapse and a brief bout of bystander CPR. When the paramedics arrived on scene, he had a weak pulse and was only responding to painful stimuli. The ECG en route revealed a very strange appearing wide complex bradycardia, almost like a sine wave, and a VBG reveals a K+ of 9 mmol/L…

First10EM Hyperkalemia ECG K9.9 from Life in the Fastlane.jpg

#FOAMed Medical Education Resources (LITFL) / CC BY-NC-SA 4.0


Continue reading “Management of life-threatening hyperkalemia”

Articles of the month (December 2015)

A monthly collection of the most interesting emergency medical literature I have encountered.

Another month and another set of articles proving only that I probably should have spent more time Christmas shopping and less reading journals. Enjoy…

Peripheral thermometers mostly suck, but does it matter?

Niven DJ, Gaudet JE, Laupland KB, Mrklas KJ, Roberts DJ, Stelfox HT. Accuracy of Peripheral Thermometers for Estimating Temperature: A Systematic Review and Meta-analysis. Annals of internal medicine. 163(10):768-77. 2015. PMID: 26571241

I will start this month with a paper just for my friend Dr. Scott Kapoor. This is a systematic review and meta-analysis of 75 studies encompassing 8682 patients looking to compare the accuracy of peripheral thermometers to central thermometers. The peripheral thermometers are not very accurate, especially if you look at hypo or hyperthermia. If you take the core temperature as the gold standard, the peripheral thermometers had a pooled sensitivity and specificity of 64% (95%CI 55-72%) and 96% (95%CI 93-97%) respectively for fever. I don’t have access to the appendices to look at the raw data, but the authors report that all peripheral thermometers were equally bad, with axillary probably being the worst. So sorry Scott, it’s not just the temporal artery thermometers that don’t work, it’s everything peripheral. Luckily, for the vast majority of people being triaged, temperature is irrelevant. For patients you care about, you probably should recheck a core temp.

Bottom line: There is a very good chance peripheral thermometers will miss a fever.


If all your friends jumped off a bridge…

Douketis JD, Spyropoulos AC, Kaatz S. Perioperative Bridging Anticoagulation in Patients with Atrial Fibrillation. The New England journal of medicine. 373(9):823-33. 2015. PMID: 26095867 [free full text]

We frequently admit patients on anticoagulants who will require surgery or procedures that require their anticoagulants to be held. Should we be bridging these patients with some kind of heparin? This is a randomized controlled trial of 1884 adult patients with chronic atrial fibrillation and at least 1 CHADS2 risk factor undergoing surgery (excluding cardiac, neuro, and spinal surgeries). They were randomized to either bridging with dalteparin or placebo. Patients were excluded if the had a mechanical heart valve, recent stroke, or renal failure. The primary outcome of any arterial thromboembolic disease was noninferior, with 4 patients (0.4%) in the non-bridged group and 3 patients (0.3%) in the bridged group having events. Major bleeding was higher in the bridged group (29 patients (3.2%) versus 12 patients (1.3%) p=0.005 NNH=53). Minor bleeding was also increased (20% versus 12%, p<0.001, NNH=11).

Bottom line: This is probably the best evidence to date that the short term risk for atrial fibrillation patients off anticoagulation is low and that bridging therapy is harmful.

Steinberg BA, Peterson ED, Kim S. Use and outcomes associated with bridging during anticoagulation interruptions in patients with atrial fibrillation: findings from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF). Circulation. 131(5):488-94. 2015. PMID: 25499873 [full free text]

This is a retrospective look at a large atrial fibrillation patient registry. They looked at the 2803 patients with non-valvular atrial fibrillation who had an interruption in their anticoagulation, primarily for non-cardiac surgery or endoscopy. 77% of patients were not bridged as compared to 23% who were. Overall adverse events were higher in the bridging group (5.3% versus 2.8% p=0.01), primarily driven by excess bleeding complications. Stroke and MI were not different between the groups. Of course, patients were not randomized, so there were likely reasons that physicians chose to bridge some patients and not others, making any concrete conclusions difficult.

Bottom line: More evidence that bridging is not helpful

As a side note, if all my friends jumped off a bridge, you can bet that I would too. My friends are all sane and mostly intelligent. If they were jumping off a bridge, there is probably a very good reason to do so, like the bridge is on fire or there is rapidly approaching school of flying sharks with lasers on their heads. Also, even if they happened to die, who wants to live in a world where all your friends just died jumping off a bridge?


OK, those were boring topics. Let’s move on: anyone have a VIP guest in the department this holiday season?

Straube S, Fan X. The occupational health of Santa Claus. Journal of occupational medicine and toxicology (London, England). 10:44. 2015. PMID: 26692887 [free full text]

Sadly, this article was a little boring even for a Christmas spoof – but have you ever considered the extreme occupational hazards of Santa Claus? Don’t be surprised if he ends up in an ED near you sometime soon.


Christmas: so many new toys, with so many small parts. It’s the perfect storm for foreign bodies in the airway

Eren S, Balci AE, Dikici B, Doblan M, Eren MN. Foreign body aspiration in children: experience of 1160 cases. Annals of tropical paediatrics. 23(1):31-7. 2003. PMID: 12648322

This is a retrospective review of 1160 children (under 15 years of age) who underwent bronchoscopy for foreign bodies. Almost 2/3rds of the patients with foreign bodies had negative radiography. (There is obviously a selection bias here, because these are only the children in whom the clinicians were concerned enough to perform a bronchoscopy). I will also note that this is an interesting population, because 38% of the foreign bodies were watermelon seeds. However, with a good story, xray is clearly not good enough to exclude foreign bodies.

Bottom line: It is often a difficult sell, but if a child has a good story for aspiration, they probably need a bronchoscopy.


 High flow nasal oxygen in the ED

Bell N, Hutchinson CL, Green TC, Rogan E, Bein KJ, Dinh MM. Randomised control trial of humidified high flow nasal cannulae versus standard oxygen in the emergency department. Emergency medicine Australasia : EMA. 2015. PMID: 26419650

This is an unblinded prospective randomized control trial comparing high flow nasal oxygen to standard care (nasal prongs or face mask) in 100 adult emergency department patients with shortness of breath, a respiratory rate over 24 and an oxygen saturation less than 94%. There were 2 primary outcomes, which is not good from a trial design perspective. For the outcome of a reduction in respiratory rate by 20% within 2 hours, the high flow nasal group was better (66.7% vs 38.5%, p=0.005). For the outcome of an escalation of ventilation requirement, the reported outcomes are less clear, because they included being changed from face mask to high flow nasal oxygen as an “escalation of care”, even though this trial is supposed to be determining if it is any better. Two patients in each group required non-invasive positive pressure ventilation, and one patient was intubated. So I would say there was no change in patient oriented outcomes except the single intubation, and a single outcome is just not enough to draw any conclusions from.

Bottom line: Not a lot to go on here, but it doesn’t look like high flow nasal oxygen will be worse than usual care.


 One step closer to forgetting antibiotics in diverticulitis

Isacson D, Thorisson A, Andreasson K, Nikberg M, Smedh K, Chabok A. Outpatient, non-antibiotic management in acute uncomplicated diverticulitis: a prospective study. International journal of colorectal disease. 30(9):1229-34. 2015. PMID: 25989930

I have previously talked about the few RCTs indicating that antibiotics might not help in diverticulitis. It is an interesting topic, so I will include new evidence as I find it. This is a prospective cohort of 155 adult patients diagnosed with acute uncomplicated diverticulitis who were managed as outpatients without antibiotics, just pain control and a diet progressing from liquids back to full, as tolerated. Of the 155 patients, only 4 patients (2.5%) failed this outpatient management strategy – which isn’t much different from what you would expect if they had been treated with antibiotics. The biggest problem with this data set is that it doesn’t represent consecutive patients. 66 patients with uncomplicated diverticulitis were seen during the study period but were not enrolled, so there could be some selection bias. There was no control, so antibiotics could have lowered complication rates further – but for the 97.5% of patients without complications, it doesn’t seem that antibiotics were necessary.

Bottom line: A little more evidence indicating that antibiotics may be unnecessary for diverticulitis after all.


 How do fish get high? Seaweed

Vandrey R, Raber JC, Raber ME, Douglass B, Miller C, Bonn-Miller MO. Cannabinoid Dose and Label Accuracy in Edible Medical Cannabis Products. JAMA. 313(24):2491-3. 2015. PMID: 26103034 [free full text]

With legal marijuana on the horizon in Canada, there are many questions we need to be asking about its use. One very basic question is: at current marijuana dispensaries, how accurate are labels with regards to THC content? Individuals were sent out to buy marijuana in San Francisco, Los Angeles, and Seattle, and the THC content was analyzed by liquid chromatography. Of 75 total samples, 13(17%) were accurately labelled, 17(23%) were under-labelled (contained more THC than the label stated), and 45 (60%) were over-labelled. Errors were frequently large, up to 55% under labelled and 99% over labelled. Combined with confusion over appropriate doses, highly concentrated doses in edibles, and differing rates of absorption, dosing errors make it more likely that marijuana users will end up in the ED.

Bottom line: Active ingredients in marijuana products are not well regulated or labelled on available products.


Monthly poll: Who would want this ENT surgeon as their own doctor?

Leopard DC, Williams RG. Nasal Foreign Bodies: A Sweet Experiment. Clinical otolaryngology : official journal of ENT-UK ; official journal of Netherlands Society for Oto-Rhino-Laryngology & Cervico-Facial Surgery. 40(5):420-1. 2015. PMID: 25639608

There are many techniques to get foreign bodies out of children’s noses, but what do you do if they don’t work? Well, if it’s a hard candy, you may not need to do anything. This (presumably bored) ENT surgeon placed 5 different candies in his own nose (Fizzers, Tic Tac, Smarties, Skittles, and Polo mints) and then had the second author perform rhinoscopy every 5 minutes. All 5 candies were completely dissolved in less than an hour. I will let you perform your own critical appraisal of these methods.

Bottom line: Watchful waiting may be reasonable for children with hard candies in their noses.

(In case you were wondering, I would happily take this chap as my doctor)


Alcohol by mouth can make you vomit. On the other hand, alcohol in the nose…

Beadle KL, Helbling AR, Love SL, April MD, Hunter CJ. Isopropyl Alcohol Nasal Inhalation for Nausea in the Emergency Department: A Randomized Controlled Trial. Annals of emergency medicine. 2015. PMID: 26679977

This is a randomized trial of a convenience sample of 80 adult patients presenting to the emergency department with a chief complaint of nausea and/or vomiting. Patients were instructed to inhale from a pad of either saline or isopropyl alcohol (the same wipes you would use on the skin before starting an IV) immediately, then 2 and 4 minutes later. Although investigators covered the label of the wipe, I’m pretty sure blinding was eliminated the instant the patient took a sniff. Nausea was measured on a scale of 0 to 10, but only for the first 10 minutes. At the start of the study, patients rated their nausea as a 6/10. At 10 minutes, the saline group still rated their nausea as 6/10 whereas the alcohol group rated theirs as 3/10 (absolute difference 3, 95%CI 2-4 p<0.001). We don’t know what happened after 10 minutes, which is a major limitation. Some other major limitations of this data are the lack of blinding and potential selection bias in a convenience sample.

Bottom line: Maybe inhaling from alcohol wipes decreases nausea

Hines S, Steels E, Chang A, Gibbons K. Aromatherapy for treatment of postoperative nausea and vomiting. The Cochrane database of systematic reviews. 4:CD007598. 2012. PMID: 22513952

Although I was completely unaware of this therapy for nausea, apparently it has been studied before. This Cochrane review found 6 RCTs and 3 non-randomized controlled trials looking at aromatherapy for nausea and vomiting. When compared to placebo, they found that isopropyl alcohol vapour inhalation reduced the number of patients requiring rescue antiemetics (RR 0.30 95%CI 0.09-1.0, p=0.05 so technically not significant), however it was less effective in reducing nausea than standard anti-emetic medications.

Bottom line: Probably shouldn’t be first line, but if I’m huffing alcohol in the break room, it may be because I caught the gastro that’s going around.

For some more on this topic, you can read about it on Academic Life in Emergency Medicine


Nerves were meant for blocking

Flores S, Herring AA. Ultrasound-guided Greater Auricular Nerve Block for Emergency Department Ear Laceration and Ear Abscess Drainage. The Journal of emergency medicine. 2015. PMID: 26589558

This is just a case report, but considering the frequency with which we see ear injuries, and the difficulty of achieving good local anesthesia, having a ultrasound guided nerve block in your back pocket is a great tool. In this article they specifically identify and anesthetize the greater auricular nerve, but a superficial cervical plexus block will get you the same coverage and might be easier. These nerve blocks only cover the posterior aspect of the ear, so you may have difficulty if the injury is more anterior. They can also miss the top of the ear.

Bottom line: Nerve blocks are fantastic for many things in the ED, especially when using ultrasound guidance.

Don’t have access to this paper? You could read about the ultrasound guided superficial cervical plexus block on NYSORA. You could also watch a video on the superficial cervical plexus block on the ultrasound podcast.


We have many effective treatments for hyperkalemia – kayexalate just isn’t one of them

Hagan AE, Farrington CA, Wall GC, Belz MM. Sodium polystyrene sulfonate for the treatment of acute hyperkalemia: a retrospective study. Clinical nephrology. 85(1):38-43. 2016. PMID: 26587776

The evidence behind the use of sodium polystyrene sulfonate (kayexalate) for hyperkalemia is poor. This is a chart review looking at 501 patients who received SPS for hyperkalemia. The chart review methods make it difficult to assess the true effect, but on average after SPS administration, the potassium decreased by 0.93mEq/L. That sounds reasonable, until you realise that the drop occurred over about 8 hours and that most of these patients were given other medications as well. The really concerning part of this paper is that there were 2 cases of bowel necrosis, a known side effect of SPS.

Bottom line: A little more evidence that reinforces my current practice – I don’t use kayexalate to treat hyperkalemia in the ED.

Want to read a little more about the original studies on kayaexalate? Check out this post by Anand Swaminathan on R.E.B.E.L.EM.


Newer is always better, right?

Navarro V, Dagron C, Elie C. Prehospital treatment with levetiracetam plus clonazepam or placebo plus clonazepam in status epilepticus (SAMUKeppra): a randomised, double-blind, phase 3 trial. The Lancet. Neurology. 15(1):47-55. 2016. PMID: 26627366

We all know the downsides of phenytoin in seizures – so it makes sense that researchers are looking at newer (but more expensive) agents. In this industry-funded, randomized, double-blind prehospital trial, they compared clonazepam plus levetiracetam (Keppra) to clonazepam plus placebo in 203 patients with status epilepticus (a seizure lasting more than 5 minutes). The trial was stopped early because an interim analysis revealed no chance that levetiracetam would turn out to be superior to placebo.

Bottom line: Don’t start changing your status epilepticus algorithms yet

Mundlamuri RC, Sinha S, Subbakrishna DK. Management of generalised convulsive status epilepticus (SE): A prospective randomised controlled study of combined treatment with intravenous lorazepam with either phenytoin, sodium valproate or levetiracetam–Pilot study. Epilepsy research. 114:52-8. 2015. PMID: 26088885

This paper complements the last. This is a prospective randomized trial of 150 patients with status epilepticus comparing valproate, phenytoin, and levetiracetam (all in addition to lorazepam). There was no statistical difference between the groups. Because of the small numbers, this is the kind of trial that could miss a clinically significant difference just because it wasn’t statistically different (type 2 error).

Bottom line: Again, there is no reason to abandon our tried and true and cheap medication yet


 Has it been cold enough for leaky gas powered heaters yet?

Hampson NB. Myth busting in carbon monoxide poisoning. The American journal of emergency medicine. 2015. PMID: 26632018

I couldn’t resist this paper – it had “myth” in the title and who doesn’t love carbon monoxide? There isn’t much to say about the the methods, as there were none, but there are a few important review points:

  1. Carbon monoxide levels do not correlate with symptoms and should not be the primary driver of emergency care
  2. A venous blood gas is just as good as an arterial gas for measuring CO levels
  3. CO is very stable in blood samples. You don’t need to rush an iced sample to the lab. In samples of anticoagulated blood, CO levels didn’t change over the course of a month. So this test could be done as an add-on if you forgot to order it initially

Bottom line: Read the three points above – stop trying to just skip to the red text to get your answers quickly

This paper was also covered on the poison review


NOT EMERGENCY MEDICINE, but in headlines everywhere

Jacobs IJ, Menon U, Ryan A et al. Ovarian cancer screening and mortality in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS): a randomised controlled trial. The Lancet. 2015. [free full text]

“Ovarian Cancer Screening Could Reduce Deaths By As Much As 20 Percent”. That is the first headline I encountered, but there are many many more. Expect to hear about this from patients, family, and friends alike. But what did the study actually show? This is a massive prospective trial that randomized 202,638 women into one of two screening protocols or a control group. Like so many cancer trials, the authors unfortunately started the trial very confused and made their primary outcome the factitious ‘disease specific mortality’ instead of all cause mortality. THEY DON’T EVEN REPORT ALL CAUSE MORTALITY! How can you tell if an intervention saves lives if you don’t measure mortality? Disease specific mortality only tells you that there might be changes in what someone happened to write on a death certificate (almost never supported by an autopsy), so is clearly not a patient oriented outcome. That is such a fatal flaw that it is hardly worth noting that there was a significant selection bias (in that healthy individuals are much more likely to volunteer for a study like this), that they had to alter the study protocol part way through, and that if you use the primary statistical outcome listed in the original trial design none of the outcomes were statistically significant. So throw this one into the trash heap, but be prepare for a lot of questions about how this could be the next big thing.

Bottom line: We need to get cancer researchers to start measuring and reporting all cause mortality. Our patients are being confused and harmed by the statistical misinformation that results from the fictional concept of ‘disease specific mortality’

You can read a much more through an intelligent review of this paper by the amazing Casey Parker on Broome Docs.


Cheesy joke of the month

What do you get if you eat Christmas decorations?


Tinsilitis!


#FOAMed of the month

A few videos that demonstrate why you should have a PEEP valve already attached to every BVM you use in the ED (rather than hidden in an RT office somewhere):

Lung Recruitment by Apneic CPAP by George Kovacs via EMCrit

PEEP your glove by George Kovacs

Amazing PEEP 1 –  BVM by AIME

Amazing PEEP 2 – ETT by AIME

Oxygenation – Understanding your BVM Device 2 by George Kovacs

When I started this month’s articles, I only planned on including the videos on the PEEP valve, but then Dr. Kovacs had to release one of the best awake intubation videos ever made. In the end, fully awake, he will show you his own carina:

Airway topicalization for an awake carina selfie

So bottom line of all this, follow George Kovacs and AIME on youtube