There are a lot of recurrent themes in this month’s edition (which has clearly shifted from being a monthly to a bimonthly publication). Podcast over on BroomeDocs.
My monthly summaries of the medical literature
Every month I select the best medical articles I have read and provide brief summaries and critical appraisals. Here are this month’s articles:
The paper you are most likely to hear about this month: antibiotics and abscesses
Talan DA, Mower WR, Krishnadasan A. Trimethoprim-Sulfamethoxazole versus Placebo for Uncomplicated Skin Abscess. The New England journal of medicine. 374(9):823-32. 2016. PMID: 26962903
Until now, the data on abscess management has been pretty clear: all you need is cold hard steel. No packing, and definitely no antibiotics. Has management just become much more confusing? This is a large, multi-center RCT comparing trimethoprim-sulfamethoxazole (320mg/1600mg MID for 1 week) to placebo in 1247 adult patients with acute abscess greater than 2cm in diameter. For the primary outcome of clinical cure at 7 days, the antibiotics group was better (80.5% versus 73.6%; absolute difference 6.9% 95%CI 2.1-11.7%; NNT = 14). There were also decreases in several secondary outcomes, such as new skin infections at other sites. However, there was an increase in GI side effects by about 7% (42.7% vs 36.1%). A cure rate of only 75% is really low and doesn’t represent the patients I see. This is probably because these are not simple abscess, with a median cellulitis area of 6.5×5.0cm, 20% of the cohort with a cellulitis area greater than 75cm2, and many patients “met other guideline criteria for antibiotics treatment”. (You can read some other opinions on REBEL EM, EM Nerd, and EM Literature of Note.)
Bottom line: This isn’t a game changing paper. It tells you to keep using antibiotics in the patients you are already using them in – complex abscesses with cellulitis – and doesn’t tell us a lot about the average abscess.
How ready are you for a mass casualty event?
Bhalla MC, Frey J, Rider C, Nord M, Hegerhorst M. Simple Triage Algorithm and Rapid Treatment and Sort, Assess, Lifesaving, Interventions, Treatment, and Transportation mass casualty triage methods for sensitivity, specificity, and predictive values. The American journal of emergency medicine. 33(11):1687-91. 2015. PMID: 26349777
I found this paper fascinating. I won’t get into detail about the performance of the scores, because the data is retrospective, and there is too much information that these scores use that would not be well recorded. However, I think this is a great study to read. I had never been exposed to a mass casualty triage system before, nor do I think I have been adequately trained in this aspect of emergency medicine. The algorithms are interesting. It’s worth a read.
Bottom line: Are you for a mass casualty event? This article might help
How do you tell if a patient needs more pain medication? Ask them
Chang AK, Bijur PE, Holden L, Gallagher EJ. Efficacy of an Acute Pain Titration Protocol Driven by Patient Response to a Simple Query: Do You Want More Pain Medication? Annals of emergency medicine. 2015. PMID: 26074387
I am strongly biased to like this study, because I was always thaught this is the way that pain medicine should be given (by Jerry Hoffman, I think). This is a prospective cohort of 215 adult patients presenting to the ED for acute painful conditions that the attending physician thought required an opioid. All patients received hydromorphone 1mg IV, followed by up to 3 more 1mg IV doses every 30 minutes driven entirely by their response to the question “Do you want more pain medication?” There were delays in administration of medication, so the max was actually 4mg over 4 hours. 205 of the 207 patients (99% 95%CI 97-100%) achieved pain control on 1 or more occasions during the study; 97% were either satisfied or very satisfied with their pain treatment. About 20% of patients wanted more pain meds at each interval. What can we learn from this study? The design of the study allows us to conclude that this method will leave most people satisfied with their pain control, and that almost everyone will reach a point where they don’t want any more analgesia. However, with no comparison, we have no idea if this technique is any better or worse than other methods. Personally, I am interested in how this would compare to patient controlled analgesia – which would require a larger upfront investment, but I think would be more tolerable for nursing workloads.
Bottom line: Asking patients is a reasonable method to determine if they need more analgesia
2 is not be better than 1 when in comes to needles
Martin SP, Chu KH, Mahmoud I, Greenslade JH, Brown AF. Double-dorsal versus single-volar digital subcutaneous anaesthetic injection for finger injuries in the emergency department: A randomised controlled trial. Emergency medicine Australasia : EMA. 2016. PMID: 26991958
Injections in the palm always seemed painful to me, so I always stuck with the double dorsal injection technique. I don’t remember why I changed, but my success rate is much better with the single palmar injection, so I’ve never looked back. The study: 86 adult patients in an RCT comparing a double-dorsal to a single-palmar injection technique for digital nerve block. There was no difference in the pain of injection between the two techniques (almost 4/10). The techniques were equally successful (65% success with double-dorsal and 72% with single-palmar). Really, none of those numbers are great.
Bottom line: Stick with the bloc you are used to – and maybe add some bicarb to get the pain on injection down?
Dumb and dumberer
Maltese F, Adda M, Bablon A. Night shift decreases cognitive performance of ICU physicians. Intensive care medicine. 42(3):393-400. 2016. PMID: 26556616
This is a prospective, randomized, cross-over study of 51 ICU doctors (27 residents, 21 attendings) who were randomized to either work a night shift or rest at home (and then were crossed over to the opposite group). Between 10am and noon the next day they went through a series of psychological tests. Not surprisingly, working memory, information process speed, and perceptual reasoning were all worse after a night shift. Cognitive flexibility was not statistically different. The clear issue with the study is we have no idea how these psychological tests translate into patient care, or whether the measured differences are actually clinically important differences.
Bottom line: Night shifts are hard. It’s hard to make good decisions at 4am. (One of many reasons I like the idea of casino shifts).
How safe is that treatment really?
Saini P, Loke YK, Gamble C, Altman DG, Williamson PR, Kirkham JJ. Selective reporting bias of harm outcomes within studies: findings from a cohort of systematic reviews. BMJ (Clinical research ed.). 349:g6501. 2014. PMID: 25416499 [free full text]
These authors attempt to examine the accuracy of reporting of harms in clinical trials. They identified trials that had been included in systematic reviews, and then evaluated each trial for how they reported harms (ie, harms measured and reported, harms not measured, harms measured but only partially reported, harms not even mentioned…). When looking at all Cochrane reviews, they found that the studies only partially reported or didn’t report harms at all 76% of the time. In a group a systematic review designed specifically to look at adverse events, 47% of studies still did not report or only partially reported a single primary harm outcome. This tendency of the literature has been discussed before. We tend to minimize our discussion of harms, which obviously skews our conclusions when looking at the entirety of the literature.
Bottom line: For every medicine you use, remember that the harms are probably greater than those reported in clinical trials
Clinical correlation required
Mark DG, Sonne DC, Jun P. False negative interpretations of cranial computed tomography in aneurysmal subarachnoid hemorrhage. Academic emergency medicine : official journal of the Society for Academic Emergency Medicine. 2016. PMID: 26918885
This is a chart review that identified 452 patients diagnosed with subarachnoid hemorrhage, and looked at the subset of 18 patients (4%) who were diagnosed by lumbar puncture after a normal CT. The supposedly normal CTs were then reviewed by 2 speciality neuro-radiologists, and in 9 of the 18 (50%) the neuro-radiologists thought there was evidence of bleed on the scan initially reported as normal. The false negative rate was 71% (5 of 7) for the scans done within 6 hours of headache. Of course, re-reading studies without the time pressures of a normal shift, especially when LPs have already shown blood (although these radiologists were blinded) might be easier.
Bottom line: Radiology isn’t perfect. Not all radiologists are created equal. This might still be the fatal flaw in the famous Perry study
But doc, it hurts A LOT
Body R, Lewis PS, Carley S, Burrows G, Haves B, Cook G. Chest pain: if it hurts a lot, is heart attack more likely? European journal of emergency medicine : official journal of the European Society for Emergency Medicine. 23(2):89-94. 2016. PMID: 25340995
Does the pain score correlate with the chance of MI? This is a secondary analysis of a data set collected for a prospective cohort study that included emergency department patients with suspected cardiac chest pain. They looked at the pain scores of the patients with a final diagnosis of MI, as compared with those who ruled out. Although there was a statistical difference, with the average pain in the MI group being 8/10 (interquartile range 5-8) and the non-MI group being 7/10 (IQR 6-8) (p=0.03), those numbers obviously don’t help clinically. This is reinforced by their analysis that showed the area under the receiver operating curve was 0.58, so essentially a coin flip. The amount of pain might have influenced the original physicians in terms of who was included in the dataset, which would skew these numbers.
Bottom line: The intensity of pain does not seem to help diagnostically in ACS.
Not the worry, that blurry vision and headache should be gone in … 90 days?
Kriz PK, Stein C, Kent J. Physical Maturity and Concussion Symptom Duration among Adolescent Ice Hockey Players. The Journal of pediatrics. 2016. PMID: 26781190
How long do pediatric concussion symptoms last? This is a prospective cohort of 145 patients aged 13-18 years who were referred to a sports medicine clinic. The mean symptom duration was 45 days (though with wide confidence intervals of +/- 49 days). About half (48%) of patients had symptoms for more than 28 days, and 13% had symptoms beyond 90 days. So perhaps concussion symptoms last longer than we usually counsel, but I worry about a significant selection bias here, as we don’t refer most kids with concussion to sport medicine clinics, and this is only 145 children from 3 clinics over 2.5 years. It probably represents the worst case scenario.
Bottom line: Some children will have prolonged concussion symptoms. Counselling and follow up instructions should keep this in mind
I have to say, the heart is what won me over when it comes to POCUS
Martindale JL, Wakai A, Collins SP. Diagnosing Acute Heart Failure in the Emergency Department: A Systematic Review and Meta-analysis. Academic emergency medicine : official journal of the Society for Academic Emergency Medicine. 2015. PMID: 26910112
This is a systematic review looking the diagnosis of congestive heart failure in the emergency department. Probably because CHF actually encompasses a few different underlying pathologies, their major finding was that no factors were good enough to single handedly rule in or rule out CHF. Some likelihood ratios: Audible S3 +LR 4.0, CXR signs of edema +LR 4.8, B lines on bedside US +LR 7.4, no B-lines -LR 0.16, and reduced ejection fraction on bedside echo +LR 4.1. (Remember you want a positive likelihood ratio of 10 or more to rule in, and a negative likelihood ratio of 0.1 or less to rule out.)
Bottom line: Ultrasound may be our best tool for diagnosing CHF, but no findings can be used in isolation to rule in or rule out the disease.
There are now bottles of water labeled “gluten free”
Zanini B, Baschè R, Ferraresi A. Randomised clinical study: gluten challenge induces symptom recurrence in only a minority of patients who meet clinical criteria for non-coeliac gluten sensitivity. Alimentary pharmacology & therapeutics. 42(8):968-76. 2015. PMID: 26310131
I get asked a lot about gluten, as I am sure many people do, not just by emergency medicine patients, but also friends and families. In this study they took 35 patients who had tested negative for celiac disease but self-identified as being gluten intolerant and in a double blind, cross-over design they exposed the patients to either gluten free or normal flour. 12 (49%) of the patients thought the gluten-free flour contained gluten – what you might guess if the guess was pure chance. I think the evidence is pretty convincing that gluten is not the issue for most people without celiac disease. These patients definitely have symptoms, but there are almost certainly other etiologies than gluten. I worry that the focus on gluten pushed by some ‘experts’ is doing patients a disservice.
Bottom line: In people without celiac disease, symptoms are not consistently reproduced by gluten.
The case of the killer iPhone
Tri JL, Severson RP, Hyberger LK, Hayes DL. Use of cellular telephones in the hospital environment. Mayo Clinic proceedings. 82(3):282-5. 2007. PMID: 17352363
These authors brought 2 telephones into different patient rooms and made phone calls while observing various medical devices. In total they did 300 tests of 192 difference devices in 75 patient rooms, and they were unable to document a single case of the cellular telephone interfering with medical equipment.
Bottom line: The ban on cel phones may be based on a myth?
Lawrentschuk N, Bolton DM. Mobile phone interference with medical equipment and its clinical relevance: a systematic review. The Medical journal of Australia. 181(3):145-9. 2004. PMID: 15287832 [free full text]
This is a systematic review looking at the question of mobile phone interference with medical equipment. They identified 8 studies that tested a total of 936 devices. (Studies ranged from 1994-2002, so technology may have changed since.) They found that interference did occur in as many as 6% of tests. However, essentially all of this interference occurred when the phone was within 1 meter of the device – so you probably have to be trying to cause interference, like they were in these studies, rather than just using phones normally. Also, the results of the interference were not recorded, so it’s difficult to know if any of it was clinically relevant. (Some brief interference on an ECG monitor is irrelevant, but I would care about a pacemaker that stopped pacing.)
Bottom line: This is a little more complex than the last paper indicated, but it appears phones are safe as long as they are more than a meter from medical equipment. (Although that might be hard in some of the cramped resuscitation rooms I have worked in.)
NSAIDs for 11/10 pain
Pathan SA, Mitra B, Straney LD. Delivering safe and effective analgesia for management of renal colic in the emergency department: a double-blind, multigroup, randomised controlled trial. Lancet (London, England). 2016. PMID: 26993881
This is a double blind RCT of 1644 adult patients with renal colic (1316 confirmed on CT) comparing morphine (0.1mg/kg IV) to diclofenac (75mg IM) to acetaminophen (1 gram IV). For a primary outcome of a 50% reduction in pain at 30 minutes, diclofenac was more effective than either morphine or acetaminophen, which weren’t different from each other (OR 1·35, 95% CI 1·05-1·73, p=0·0187). This means that 68% of the diclofenac group had a 50% reduction in pain, as compared to 61% with morphine and 66% with acetaminophen – not a huge absolute difference. One interesting number is that only 12% of the IM diclofenac group needed any rescue medication, so it might be possible to manage renal colic without ever starting an IV. Adverse events were statistically higher in the morphine group, but really quite low (1-3%) in all groups. Personally, I like a multimodal pain approach, and will probably continue to combine NSAIDS and opioids.
Bottom line: It might be true that NSAIDs are slightly more effective in renal colic
#FOAMed of the Month
This is a really short post on the Nurse Path, but I love it because it is a simple yet brilliant method for improving communication and patient safety. The key is that for medication checks, rather than reading out the dose and asking the person confirm ‘yes or no’, which could result in confirmation bias or error, you simply ask “what is this?” That forces the other person to slow down and actually read the medication out loud. I imagine this technique could also be used in another of other situations as well.
Cheesy Joke of the Month
Two orthopedic surgeons are on opposite sides of a lake.
One surgeon yells to the other, “How do you get to the other side?”
The other responds, “You are on the other side!”
A monthly collection of the most interesting emergency medical literature I have encountered.
Here is this month’s summary of my favorite reads from the medical literature…
Bronchiolitis – it will take your breath away
Willwerth BM, Harper MB, Greenes DS. Identifying hospitalized infants who have bronchiolitis and are at high risk for apnea. Ann Emerg Med. 2006;48:(4)441-7. PMID: 16997681
Its that time of year. Some children are beginning to hold their breath in anticipation of Christmas. Or, maybe that was an apneic spell from bronchiolitis? Which children are at risk? This is a retrospective cohort of 691 children less than 6 months old who were admitted to the hospital for bronchiolitis looking at risk factors associated with apnea. The authors found that full term babies less than 1 month old, preterm babies less than 48 weeks post-conception, and babies whose caregivers had already witnessed an apnea spell were at higher risk for further apnea spells. Overall 19 (2.5% 95%CI 1.7-4.3) children had apnea spells while admitted, and all 19 met one of the criteria above.
Bottom line: 2.5% is relatively low risk, but breathing is relatively important. I would have the pediatricians review the kids that fall into these categories.
More bronchiolitis and the need for oxygen
Cunningham S, Rodriguez A, Adams T. Oxygen saturation targets in infants with bronchiolitis (BIDS): a double-blind, randomised, equivalence trial. Lancet (London, England). 386(9998):1041-8. 2015. PMID: 26382998
This is a multi-center, randomized, controlled trial of children aged 6 weeks to 12 months admitted to hospital with bronchiolitis. This children were either placed on a standard sat probe or one that was altered so that a sat of 90% would display as 94%. Staff were instructed to provide oxygen to any child with a sat less than 94%. (94% seems like a pretty high target. I am more interested in whether we should be starting oxygen at say 92% or 88% or even lower.) I think they chose a pretty poor primary outcome: time to resolution of cough. For what it’s worth, it was equivalent, but did we really think oxygen could cure cough? Some secondary outcomes were also not affected, but none capture why I give oxygen. Oxygen is given when children are approaching the steep portion of the oxygen-hemoglobin dissociation curve to prevent precipitous drops, desaturations, and bad outcomes. The authors do report no change in ‘adverse events’, but if you look at the supplement, respiratory adverse events were things like cough and otitis media. Although I believe we probably over-treat bronchiolitis, this is another in a slew of papers that fails to actually prove that it is safe to withhold oxygen or discharge patients with low oxygen saturations.
Bottom line: Oxygen saturation is still an important parameter to monitor in bronchiolitis. We don’t know the ideal saturation to target.
Children inhaling salt water – no, not drowning, but bronchiolitis treatment
Silver AH, Esteban-Cruciani N, Azzarone G. 3% Hypertonic Saline Versus Normal Saline in Inpatient Bronchiolitis: A Randomized Controlled Trial. Pediatrics. 2015. PMID: 26553190
This is a randomized, double-blind, controlled trial from a single pediatric hospital comparing 4 ml of either 3% saline or 0.9% saline nebulized every 4 hours in 227 children under 12 months old with bronchiolitis. There was no difference in any of the many outcomes they measured, including length of stay, ICU admission, readmission, and objective respiratory findings. Of course, it’s possible that normal saline is more therapeutic than no treatment – but, come on, you know that nothing works in bronchiolitis.
Bottom line: No treatments work in bronchiolitis. Do you think we will ever come to terms with that?
It might just be the season, but it seems like I am obsessed with wheezing kids
Cronin JJ, McCoy S, Kennedy U. A Randomized Trial of Single-Dose Oral Dexamethasone Versus Multidose Prednisolone for Acute Exacerbations of Asthma in Children Who Attend the Emergency Department. Annals of emergency medicine. 2015. PMID: 26460983
I have covered dexamethasone versus prednisone for asthma before, but here is another RCT. In 245 pediatric patients (aged 2-16) with asthma, they compared a single dose of dexamethasone (0.3mg/kg) to prednisolone (1mg/kg) for 3 days. Their primary outcome was a PRAM score on day 4 and there was no difference between the two.
Bottom line: I will continue using the easier single dose dexamethasone over prednisone.
More shots fired in the continuing Roc versus Sux RSI battle
Tran DT, Newton EK, Mount VA, Lee JS, Wells GA, Perry JJ. Rocuronium versus succinylcholine for rapid sequence induction intubation. The Cochrane database of systematic reviews. 10:CD002788. 2015. PMID: 26512948
This one is going to ruffle a few feathers. Let’s start with the author’s conclusions: “Succinylcholine created superior intubation conditions to rocuronium in achieving excellent and clinically acceptable intubating conditions.” This is a cochrane review that includes 50 trials covering 4151 patients. For “excellent intubating conditions” succinylcholine was superior to rocuronium (RR 0.86 95%CI 0.81-0.92). The problem with this conclusion is the significant heterogeneity in the included studies. For me, the biggest concern is varying doses. In fact, the authors even conclude that if you use 1.2mg/kg of rocuronium (the appropriate dose for RSI) there was no difference between roc and sux. Unfortunately, they make the erroneous conclusion that sux is still better because it has a shorter duration of paralysis. In emergent airways, short paralysis is not a good thing.
Bottom line: Ignore the conclusions, rocuronium at a proper dose (1.2mg/kg) is a great paralytic for RSI.
One of my favorite myths to rant about – and apparently some very smart people out there agree with me
Swaminathan A, Otterness K, Milne K, Rezaie S. The Safety of Topical Anesthetics in the Treatment of Corneal Abrasions: A Review. The Journal of emergency medicine. 49(5):810-5. 2015. 26281814
I spoke about topical anesthetics for corneal abrasions at rounds earlier this year. (My handout from that talk can be found here.) This is a systematic review looking at the same topic. They identify 2 emergency department studies and 4 ophthalmology studies (after a procedure called photorefractive keratectomy – essentially a iatrogenic corneal abrasion) that prospectively evaluated the use of topical anesthetics for corneal abrasions. All the studies were small. Topical anesthetics resulted in no complications. Overall, topical anesthetics appear to be effective, with clinically and statistically significant pain score reduction in 5 of 6 studies.
Bottom line: Treat your patient’s pain. A short course of topical anesthetic is probably safe and almost certainly effective for corneal abrasions.
Acute HIV – a diagnosis I am probably missing
Early HIV infection presents as a mononucleosis-like infection, making it very difficult to diagnose. Although I generally dislike using the emergency department for public health screening, if HIV is not diagnosed during this initial stage, many years may pass before it is diagnosed, not only hurting the patient, but also putting their many contacts at risk. This is a letter to the editor describing a study where they retrospectively took all blood samples that were sent for epstein barr virus at Massachusetts General Hospital and tested them for HIV RNA. They found that 1.2% (7/563) has an acute HIV infection and another 0.8% (4/563) had chronic HIV.
Bottom line: This is well above the threshold for screening for HIV. Perhaps monospot and HIV testing should be paired?
1 more: Non specific viral illness or acute HIV?
Pincus JM, Crosby SS, Losina E, King ER, LaBelle C, Freedberg KA. Acute human immunodeficiency virus infection in patients presenting to an urban urgent care center. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. 37(12):1699-704. 2003. PMID: 14689354 [free full text]
Sticking with the same topic, these authors tested all patients presenting with viral symptoms and 1 or more HIV risk factors at their urban urgent care centre for HIV. (They were very broad with their HIV risk factors: any sexual contact, any injection drug use, any crack use, or any alcohol use in the last 2 months.) Of the 499 patients included, 5 (1.0%) were diagnosed with an acute HIV infection and another 6 (1.2%) were diagnosed with chronic HIV. They did not have any false positives.
Bottom line: Depending on your work environment, it may be worth screening for HIV in patients with viral illnesses.
It’s all about that aVL
Bischof JE, Worrall C, Thompson P, Marti D, Smith SW. ST depression in lead aVL differentiates inferior ST-elevation myocardial infarction from pericarditis. The American journal of emergency medicine. 2015. PMID: 26542793
Is that Inferior ST elevation indicative of STEMI? Or is it pericarditis? aVL might hold the key. This is a retrospective look at 3 different groups. Of 154 patients with a final diagnosis of inferior STEMI, all 154 had some degree of ST depression in aVL. Of the 49 patients with pericarditis, 49 had some degree of inferior ST elevation, but none had any ST depression in aVL. There was a third cohort with subtle inferior ST elevation (less than 1mm) but confirmed vessel occlusion on cath. Of these 54 patients, 49 had ST depression in aVL. The authors conclude that ST depression is highly sensitive for inferior STEMI and specific for pericarditis.
Bottom line: I will certainly look at aVL, but would love to see this repeated prospectively
If you want to read more about this and see some example ECGs, check out the blog post by senior author Dr Steve Smith: http://hqmeded-ecg.blogspot.ca/2015/11/new-paper-published-on-significance-of.html
Cold – the pure green coffee (ask Dr. Oz) of the brain
Another in the cold brain is not healthy brain category. This is a multicentre, randomized controlled trial of 387 adult patients (out of 2498 screened patients) with traumatic brain injury and persistently elevated ICP after sedation, elevation of the head of the bed, and mechanical ventilation. They were randomized to either get or not get hypothermia (target between 32 and 35 degrees Celsius for 48 hours.) The trial was stopped early for harm. Their primary outcome (neuro status based on the extended Glasgow outcome scale) was worse in the hypothermia group (OR 1.53 95%CI 1.02-2.30). Mortality was also worse (OR 1.45 95%CI 1.01-2.10). The biggest problem with the study was that they included patients up to 10 days after injury, which could just be too late for the magical power of cold to work.
However, I don’t think we should find this too surprising. Hypothermia has been tried for many conditions, including TBI, in the past with limited success. The general failure of hypothermia is one of the reasons to remain highly skeptical of those two small, biased trials that indicated that it worked in cardiac arrest. It may be reasonable to continue using hypothermia for the time being, but if anyone gets around to actually repeating the hypothermia versus placebo trial in cardiac arrest, we shouldn’t be surprised if it turns out to have no effect.
Bottom line: No hypothermia for trauma
Dual antiplatelets for stroke/TIA?
Wang Y, Pan Y, Zhao X. Clopidogrel With Aspirin in Acute Minor Stroke or Transient Ischemic Attack (CHANCE) Trial: One-Year Outcomes. Circulation. 132(1):40-6. 2015. PMID: 25957224
This is one of those trials that will get talked about, but I worry we will over apply the results. This is a large multicenter randomized trial in which 5170 Chinese patients with high risk TIA or minor CVA were randomized to either clopidogrel 75mg daily for 3 months plus aspirin 75 mg daily for 21 days or aspirin 75 mg daily for 3 months. The primary outcome of stroke at 1 year occurred in 10.6% of the combo group as compared to 14.0% of the aspirin alone group (hazard ratio, 0.78; 95% confidence interval, 0.65-0.93; P=0.006). Bleeding was the same in both groups. I think there are a few important caveats. First, you should question the generalizability of these results to your patients unless you work in China, because the rates of smoking in China are unlike those anywhere else in the world. Second, it is unlikely that the combination of ASA and clopidogrel has the same bleeding rates as ASA alone. That doesn’t fit well with previous studies or general experience. This should remind us that RCTs are usually not well designed to identify harms and will often over estimate the benefit to harm ratio.
Bottom line: I would not be changing my practice to include dual antiplatelet therapy based on this study alone.
Great ultrasound tip – try using both probes for IUP
Tabbut M, Harper D, Gramer D, Jones R. High-frequency linear transducer improves detection of an intrauterine pregnancy in first trimester ultrasound. The American Journal of Emergency Medicine. Article in Press. PMID:
Traditionally, we are taught to use a curvilinear abdominal probe when performing transabdominal ultrasound to detect first trimester pregnancy. This study looked at adding the high frequency linear transducer after failure to identify IUP with the standard transducer. Of 81 initial scans, 27 patients did not have an IUP visualised with the curvilinear probe. Of those, 9 (33%) were found to have an IUP by using the linear probe.
Bottom line: It’s probably worth trying the linear probe if you can’t see an IUP with the curvilinear.
Cricoid pressure: the evidence?
Algie CM, Mahar RK, Tan HB, Wilson G, Mahar PD, Wasiak J. Effectiveness and risks of cricoid pressure during rapid sequence induction for endotracheal intubation. The Cochrane database of systematic reviews. 11:CD011656. 2015. PMID: 26578526
This is a Cochrane review designed to look for any RCT evidence of the value of cricoid pressure in either emergent or elective airways. The review really says nothing of value, because there is no evidence to review. So why include it? Because sometimes it’s important to know that there is no evidence to review. If anyone ever gets too dogmatic on either side of the cricoid pressure debate, they should probably be ignored.
Bottom line: There is no evidence supporting the use of cricoid pressure. I abandoned it a long time ago, but I would be happy to see an RCT done to confirm or contradict my current practice.
Sex is better than flomax!
Doluoglu OG, Demirbas A, Kilinc MF. Can Sexual Intercourse Be an Alternative Therapy for Distal Ureteral Stones? A Prospective, Randomized, Controlled Study. Urology. 86(1):19-24. 2015. PMID: 26142575
By now, everyone should know that tamsulosin does not help patients with kidney stones, but that doesn’t mean we should give up on our patients. Is there anything else we can do to help? In this randomized, controlled study 75 adult patients with nephrolithiasis were randomized to either 1) being asked to have sex at least 3-4 times a week, 2) tamsulosin 0.4mg a day, or 3) usual care. There were no placebos (although if you can come up with a placebo version of sex I want to hear about it.) The mean time to stone expulsion was only 10 days (95%CI 4.2-15.8 days) in the sex group, versus 16.6 (95%CI 8.1-25.1 days) with tamsulosin and 18 (95%CI 15.5-23.5 days) with usual care (p=0.0001). I foresee a large number of men looking for medical notes explaining this therapy to their wives. Perhaps there may even be a few malingerers without stones looking to get this prescription?
Bottom line: Sex is good
When is dementia not dementia?
Djukic M, Wedekind D, Franz A, Gremke M, Nau R. Frequency of dementia syndromes with a potentially treatable cause in geriatric in-patients: analysis of a 1-year interval. European archives of psychiatry and clinical neuroscience. 265(5):429-38. 2015. PMID: 25716929
Dementia is a horrible diagnosis that we can’t do anything about. But is it always? In this retrospective review of patients admitted to hospital with dementia, the authors searched for reversible causes. Of the patients previously diagnosed with dementia, the authors were able identify a potentially reversible cause in 23%. Of the newly diagnosed dementia, 31% had potentially reversible causes. The common reversible causes included low B12, depression, alcoholism, and normal pressure hydrocephalus. I wouldn’t hang my hat on any of the numbers, given the retrospective nature of the trial, but this should serve as a reminder that we might be able to help some of these patients. If you can reverse dementia, that is a true save.
Bottom line: Some dementia is reversible. These causes should be searched for.
Dikembe Mutombo is wagging his finger – Block!
Riddell M, Ospina M, Holroyd-Leduc JM. Use of Femoral Nerve Blocks to Manage Hip Fracture Pain among Older Adults in the Emergency Department: A Systematic Review. CJEM. 2015. PMID: 26354332
My appraisal may be biased because I love nerve blocks, especially when I can do them with an ultrasound. This is a systematic review of randomized control trials asking the question: does the use of a femoral nerve block reduce pain, opioid use, delirium, or improve function in adults over 65 with an acute hip fracture. They found 7 RCTs covering a total of 224 patients – so the studies were small. Also, only one trial was placebo controlled. The remainder compared the nerve block to opioids. The authors appropriately did not perform a meta-analysis, as the studies were heterogenous, so a single numerical summary is not possible. The best summary is that the nerve block group consistently had both statistically and clinically significant reduction in their pain scores as compared to placebo, used less opioid, and had fewer complications.
Bottom line: Nerve blocks work great for hip fractures. We should be using these.
From Dikembe Mutombo to Mark Spitz
Browne KM, Murphy O, Clover AJ. Should we advise patients with sutures not to swim? BMJ (Clinical research ed.). 348:g3171. 2014. PMID: 24859900
I always find it a little frustrating when my non-medical friends ask me questions about medicine that seem really simple, but that I honestly can’t answer. What exactly did I learn in all those years of school? The most recent question was: “when can I started swimming again after getting stitches?” This is a review, if you can call a search that unearthed only a single case report a review, trying to answer that question. Yes, apparently in the entire medical literature there is a single reported case of a wound infection that occurred after swimming – and that was in a hospital rehab pool which is probably more likely to be colonized with strange bugs than your average swimming pool. The authors try to shape this into a practical answer, but I think the best answer we can give is “we don’t know”. Early showering after surgery has been shown to be safe, so maybe you could extrapolate from that.
Bottom line: There is much in medicine that we simply don’t know
Which is more important: rinsing your dishes before they go in the dishwasher, or rinsing out the inside of an abscess?
Chinnock B, Hendey GW. Irrigation of Cutaneous Abscesses Does Not Improve Treatment Success. Annals of emergency medicine. 2015. PMID: 26416494
I was never taught to irrigate abscesses in residency. It was only this year that I discovered that this has been suggested by numerous guidelines. But not so fast. This is a non-blinded RCT of 209 patients with cutaneous abscesses randomized to irrigation or no irrigation. There was no difference in the need for further treatment (I&D, antibiotic change, or admission) at 30 days between the 2 groups (15% vs 13%). Unfortunately a huge number of these patients were put on antibiotics (91% in the irrigation and 73% in the no irrigation group), which we know are unnecessary in most abscesses, but contaminate the results here.
Bottom line: This wasn’t common practice where I trained and we never saw many bouncebacks. I won’t start irrigating abscesses based on this.
Should the Bee Gees pause for a breath (at 30:2)?
“Well, you can tell by the way I use my walk, I’m a woman’s man. No time to talk… Ah,ha,ha,ha, stayin’ alive”. This is a large randomized controlled trial of 23,711 adult patients with out of hospital cardiac arrest comparing the standard 30:2 ratio of chest compressions to rescue breaths, to continuous chest compressions at 100/min with 10 asynchronous breaths a minute. The primary outcome of survival to hospital discharge was identical, 9.0% in the continuous chest compression group and 9.7% in the 30:2 group. Neurologically intact survival was 7.0% and 7.7% respectively. The biggest issue with the data is that everyone got extremely high quality CPR, and the compression fraction was almost identical in both groups, so it would have been difficult to demonstrate any difference.
Bottom line: Personally, I like continuous compressions with asynchronous breaths more, but this trial supports whatever you are comfortable with as long as you are doing high quality CPR.
A quick and easy rule out blood test for aortic dissection? Get real
Asha SE, Miers JW. A Systematic Review and Meta-analysis of D-dimer as a Rule-out Test for Suspected Acute Aortic Dissection. Annals of emergency medicine. 66(4):368-78. 2015. PMID: pubmed
This is a systematic review and meta-analysis looking to determine the diagnostic accuracy of D-dimer as a rule out test of aortic dissection. In total they found 5 studies including a total of 1600 patients. My first point of concern is that 1035 of those patients came from a single study, which could potentially dominate a meta-analysis, and that study was not designed to test the accuracy of D-dimer. In fact, the study enrolled 1455 patients, but only 1035 were counted in this meta-analysis, because the other patients never even had a D-dimer drawn. The results they present are pretty impressive, with a pooled sensitivity of 98% (95%CI 96-100%), specificity of 42% (95%CI 39-45%), negative likelihood ratio of 0.05 and positive likelihood ratio of 2.11. However, I would be very careful interpreting those results. Not only are the majority of the patients from a registry where D-dimer didn’t have to be drawn, but these were almost all patients admitted to CCUs, so very different from our ED population. Finally, although you would be using this test to try to avoid CTs, the poor specificity in a lower risk population could actually paradoxically lead to increased CT usage, much like D-dimer for PE.
Bottom line: This study isn’t enough to support D-dimer to rule out aortic dissection in the ED.
“Unreasonable haste is the direct road to error” – Moliere
Fanari Z, Abraham N, Kolm P. Aggressive Measures to Decrease “Door to Balloon” Time and Incidence of Unnecessary Cardiac Catheterization: Potential Risks and Role of Quality Improvement. Mayo Clinic proceedings. 2015. PMID: 26549506
An important lesson in unintended consequences. We know that short door to balloon times are important for STEMI patients. This is a study from a single hospital where they instituted a number of measures to decrease the door to balloon time. And it worked! Well – they managed to get the door to balloon time decreased by 15 minutes, which is excellent. However, it’s important to measure patient oriented outcomes and in this cohort the false positive STEMI rate rose from 7.7% to 16% and there was an increased mortality in this false positive group.
Bottom line: Inappropriate benchmarks can result in physicians rushing, more errors, and patient harms.
Don’t let an endotracheal tube make your patient worse
Kim WY, Kwak MK, Ko BS. Factors associated with the occurrence of cardiac arrest after emergency tracheal intubation in the emergency department. PloS one. 9(11):e112779. 2014. PMID: 25402500 [free full text]
Emergency physicians love procedures and intubation is one of our favorite. Sometimes this leads to us being a little overzealous about intubating very early, when an immediate airway is not necessary. This is a case control study of 41 critically ill adult patients that had a cardiac arrest after intubation (out of a total of 2404 critically ill patients who were intubated – or 1.7%.) Pre-Intubation hypotension (a systolic blood pressues ≤ 90) was independently associated with post-intubation arrest (OR 3.67 95%CI 1.58-8.55.) The case control design may not provide precise numbers, but I think this is a good reminder that some patients need good resuscitation before we attempt intubation.
Bottom line: Resuscitation before intubation in hypotensive patients
Cheesy Joke of the Month
There are two cows in a field. The first cow turns to the second and asks, “did you hear about the outbreak of mad cow disease?” The second cow responds: “Good thing I am a helicopter.”
#FOAMed of the month
Every month this section could probably just be filled with my favorite talks from SMACC. I will try to include some different FOAM in coming months, but these talks were so go that even though I listened to them live, I have listened to them all again at home. This is why I have been telling everyone who will listen they should join me in Dublin in June. The first tickets sold out very fast, but some more will go on sale December 1st at 5pm EST (if my math is right.)
For now, these talks were amazing:
Crack the chest. Get crucified. (John Hinds) – I know I have recommended this one before, but it is worth more than one watch.