The BREACH

Reviews and summaries of the latest Emergency Medicine research papers. We try to cover 10 of the best articles each month. Please visit our website for written summaries and to search past editions: www.the-breach.com

April 17th, 2019    

49. Right ventricle myocardial infarction

 

Background: A case report in 1974 was the first to mention right ventricle (RV) infarction as a distinct entity, noting that patients with this pathology exhibit "a unique clinical and haemodynamic syndrome". This is because the resulting weakness of the RV makes the patient's cardiac output extremely preload sensitive. They often present in shock and even if they are normotensive initially, giving GTN can precipitate a severe drop in blood pressure or even trigger cardiac arrest. These are an important group of patients to identify!

 

 

Thygesen K, Alpert J, Jaffe A, et al. Fourth universal definition of myocardial infarction. European Heart Journal 2019;40(3):237-269

 

 

The paper: This is another nugget from the 4th Universal Definition of Myocardial Infarction, published last year. It highlights the necessity of obtaining recordings from supplemental leads in certain patients. They note that an RV infarct is very rarely isolated but usually occurs as part of an inferior STEMI (Up To Date suggests 30-50% of inferior STEMIs have this complication). Supplemental leads V3R and V4R are placed on the right side of the chest, opposite the standard V3 and V4. ST elevation >0.5mm in either of these supplementary leads is considered diagnostic of RV infarction. Other ECG changes suggestive of RV infarction include ST elevation in aVR or V1, but several experts recommend deploying the supplemental leads in every case of inferior MI, because missing an RV infarct can be devastating for the patient.

 

 

The bottom line: Be aware of RV infarction as a potential complication of inferior STEMI and actively look for it by deploying supplemental leads. Don't give GTN to these patients! They need IV fluids in the first instance.

 

 

Note: Amal Mattu (Cardiology EM consultant at University of Maryland, USA and producer of the excellent ECG Weekly) suggests looking for the following triad to identify patients at risk of RV infarction...

- Chest pain
- Hypotension
- No crackles on auscultation

You need all three because the other main differential for MI + shock is flash pulmonary oedema.

 

 

Expert commentary:
"This is really great learning, and the triad is easily memorable."
(Dr Robert Tan, ED Consultant)

 

 

More FOAMed on this topic:
Life in the fast lane
Dr Smith's ECG blog (to take things to the next level)
ECG weekly - not quite FOAMed but (I think) the best ECG resource around and it's pretty inexpensive

 

April 10th, 2019    

48. Needle-less anaesthesia for mucosal lacerations

Background: It is difficult to treat oral mucosal lacerations in children. They are often terrified, in pain, and won't remain still enough to allow safe delivery of local anaesthetic or fine suturing. Lidocaine can either be injected locally or used in a nerve block, but both of these options are tricky in the paediatric population. The authors of the current paper present a novel approach to achieving satisfactory local anaesthesia.

 

Nickerson J, Tay ET. Dripped lidocaine: a novel approach to needleless anesthesia for mucosal lacerations. J Emerg Med 2018;55(3):405-7

 

The paper: A case series of 3 children (aged 2, 8 and 15) who presented with lip lacerations. Each received local anaesthesia by dripping 1% lidocaine into the wound at a rate of 1 drop per second until the wound was saturated with solution. Adequate anaesthesia was achieved after around 5 minutes, and each wound was sutured closed with minimum discomfort. The authors hypothesised that the increased blood supply of the oral mucosa meant that the lidocaine was readily absorbed by the wound and surrounding tissue.

 

The bottom line: If you have a child with an oral mucosal laceration that needs closing, try dripping lidocaine onto the wound to achieve local anaesthesia.

 

Note: I have personally tried this 3 times (bringing our 'collective case series' to 6!). Twice it worked like a charm. In the last case, there was some discomfort, but I was able to inject some more lidocaine to eliminate this - the drips certainly helped reduce the pain of injection.

 

Expert commentary:
"This technique is useful as LAT gel cannot be used on mucus membranes. The only potential risks are swallowing the solution and reaching the maximum dose for weight. Incidentally, there is no hard-and-fast rule about who can close lacerations across the vermilion border - it's purely about the competence of the practitioner and the agreement of the patient / parent."
(Dr Dwynwen Roberts, ED Consultant)

 

"This is a potentially amazing idea, especially in needle phobic children, ADHD, ASD, etc."
(Dr Mohsin Jafri, Paediatric Consultant)

April 4th, 2019    

47. Ultrasound for diagnosing retinal detachment

 

Background: Retinal detachment is one of several sight-threatening conditions seen in the ED. Flashes and floaters are often the first sign that something is amiss, and the standard ED workup involves slit lamp examination and fundoscopy. However, subtle abnormalities are difficult to pick up on fundoscopy, especially in the non-dilated eye. In the FOTO-ED study (2011), ED physicians only performed fundoscopy in 33 out of 350 appropriate cases, and they missed the diagnosis in every one (confirmed by photos taken of the fundus at the time of examination).

Is there a better way to check the back of the eye? The first observational trial of ocular ultrasound in the ED (17 years ago in 2002) found it to be very accurate and since then many more trials have appeared. The average 'bench-to-bedside' period is often quoted as 17 years - has the time come for ocular ultrasound to become common practice?

 

 

Gottlieb M, Holladay D, Peksa GD. Point-of-care ocular ultrasound for the diagnosis of retinal detachment: a systematic review and meta-analysis. Acad Emerg Med 2019;00:1-9

 

 

The paper: A systematic review that found 11 observational studies with a total of 844 patients. Ocular ultrasound was performed by ED physicians on patients with suspected retinal detachment, and their findings were compared to final ophthalmology diagnosis. They found that ultrasound was 94.2% sensitive and 96.3% specific for the diagnosis of retinal detachment.

 

 

The bottom line: Ocular ultrasound is both sensitive and specific for the diagnosis of retinal detachment and, with training, is probably a better examination tool than fundoscopy for this condition.

 

 

Note: The Royal College of Ophthalmologists (2010) recommend immediate referral if the patient has "visual field loss or fundoscopic signs of detachment or vitreous haemorrhage". They recommend indirect ophthalmoscopy within 24 hours if there is "no visual field loss, normal visual acuity and normal fundoscopic exam" (i.e. reported flashes and floaters only)...

So where does ocular ultrasound fit into this? If your patient has normal visual acuity and no field deficit, perform ultrasound. If there are signs of detachment, refer them immediately; if not, they can be seen the following day.

 

March 30th, 2019    

46. Can we suture dog bite wounds closed?

 

Background: The traditional teaching is to leave dog bite wounds open, allowing them to heal by secondary intention or having them closed in theatre after a thorough wash-out. The idea was that this reduced the risk of infection. The studies that led to this approach, however, have many methodological problems and are at least 30 years old. Recent research has looked at primary closure.

 

 

Paschos NK, Makris EA, Gantsos A, Georgoulis AD. Primary closure versus non-closure of dog bite wounds. A randomised controlled trial. Injury 2014;45(1):237-40

 

 

The paper: An RCT involving 168 consecutive patients with dog bite injuries. Each had their wounds cleaned using high-pressure irrigation and iodine and each received a course of prophylactic antibiotics. They were randomised to have their wounds sutured closed or left open, and were followed up at weeks 1 and 4 post-injury to determine the rate of infection and the cosmetic appearance of the wound. The overall infection rate was 8.3%, and there was no significant difference between the two groups. The cosmetic appearance at 4 weeks (independently assessed by a surgeon using the Vancouver Scar Scale) was significantly better in the sutured group.

 

 

The bottom line: This study is probably the best evidence to date (it's hard to see how they could have improved this type of trial - you can't blind the clinicians!). If dog bite wounds are carefully cleaned and debrided, and if they are not too large or complicated, it seems reasonable to close them in the ED.

 

March 27th, 2019    

45. Martial arts technique to control bleeding

 

Background: Blood loss is the leading preventable cause of death from trauma. The first, and often most effective, method of achieving haemostasis is manual compression. It is tiring to maintain pressure, however, and there are personal safety concerns about direct contact with bleeding wounds. Tourniquets are useful for extremity haemorrhage, but they are not always immediately available and take some time to apply (an average of one minute in simulations, even if the volunteers had one to hand). The authors of the current paper hypothesised that a martial arts technique could be adapted to compress major arteries and reduce blood loss.

 

 

Slevin JP, Harrison C, Da Silva E, White NJ. Martial arts technique for control of severe external bleeding. Emerg Med J 2019;0:1-5

 

 

The paper: A black belt in Brazilian Jiu-Jitsu was recruited to teach the 'knee mount' positions (see image on blog site) to the study authors, who then performed each on 11 healthy volunteers while using ultrasound to measure mean arterial blood flow velocity (MAV) in the arteries affected. MAV was significantly decreased during compression of the brachial and femoral arteries, but not the abdominal aorta. No one was injured during the study.

 

 

 

The bottom line: This is only a proof-of-concept study, but offers a potentially faster and more efficient technique for quickly reducing blood loss from an extremity wound.

 

 

Expert commentary:
"Perhaps a little limited in its application to ED but likely of interest to our paramedic colleagues. Another learning point from this is that if people performing Jiu-Jitsu present with signs suggestive of limb ischaemia or groin/axillary pain, we should consider damage to underlying vascular structures in these areas."
(Dr Robert Tan, ED Consultant)

 

March 24th, 2019    

44. Which features show us a child is not septic?

 

Background: Paediatric sepsis guidelines and decision aids are numerous, but tend to focus (rightly) on maximum sensitivity so no septic child is missed. There is of course a risk of over-diagnosis and over-treatment, but in real life we instinctively use features of wellness to reassure us that a child does not have sepsis. This gestalt develops throughout a doctor's career and can be difficult to pin down and analyse. This paper attempted to do just that by gathering expert opinion to identify a consensus on which features reduce the probability of sepsis.

 

 

Snelson E, Ramlakhan S. Which observed behaviours may reassure physicians that a child is not septic? An international Delphi study. Arch Dis Child 2018;103:864-867

 

 

The paper: A modified Delphi technique was used to survey nearly 200 paediatric consultants in two rounds with the question: "What activities or behaviours do you feel are reassuring and significantly reduce the likelihood that a febrile child has possible sepsis?" Three behaviours were reported as reassuring by over 90% of respondents:

1. Being actively energetic (e.g. running, jumping or similar)
2. Being talkative, chatty, babbling or cooing (age appropriate)
3. Playing
4. Eating (>70%)

The least reassuring behaviours were showing fear of the clinician and using an electronic device ('iPhone positive' may not be a reliable sign in kids)

 

 

The bottom line: This is the first attempt at defining wellness in febrile children. It suggests that being energetic, talkative, playing and eating are reassuring features that contribute to clinician gestalt.

 

 

Expert commentary:
"This is a very interesting study, something we constantly do in Paediatric ED but something I have difficulty teaching ("Well children look well," is commonly said but is difficult to define). This study shows the importance of looking at the child's behaviour both in a cubical and in the waiting room, and of observing them over time."
(Dr Emily Goodlad, Paediatric Consultant)

 

 

"I strongly agree with these findings. In kids, even tonsillitis can trigger the 'sepsis 6' protocol. As a paediatrician, seeing the child as a whole - smiling, playing, running around - is vital and helps us to decide the management."
(Dr Mohsin Jafri, Paediatric Consultant)

 

March 19th, 2019    

43. Is it time to retire the ABCD2 score for TIA?

 

Background: In the early 2000s, three studies were combined to develop the ABCD2 decision rule for predicting the short-term risk of stroke following a TIA (Age, Blood pressure, Clinical features, Duration of symptoms and Diabetes). These were retrospective studies using registry data. The current paper was actually the first to attempt to externally validate this rule prospectively and remains the largest ED-based study to date.

 

 

Perry JJ, Sharma M, Sivilotti MLA, et al. Prospective validation of the ABCD2 score for patients in the emergency department with transient ischemic attack. CMAJ. 2011;183(10):1137-45.

 

 

The paper: A prospective multi-centre cohort study involving 2,056 patients with a diagnosis of TIA. Each had an ABCD2 score calculated and each was followed up at 7 and 90 days to determine whether they had had a stroke or any further episodes of TIA. The final diagnosis had to be confirmed by at least two independent neurologists. An ABCD2 score of 0 or 1 was found to be 100% sensitive, but few patients fell into this category. Taking the usual UK cut-off, a score of 3 was 92% sensitive and 33% specific for predicting stroke, while a score of 4 was 66% sensitive and 57% specific (these numbers did not change significantly from 7 to 90 days). They also found that the score was calculated incorrectly in the ED in 33% of cases. The commonest error was not scoring unilateral weakness if this was mentioned in the history but was no longer present on examination.

 

 

The bottom line: The ABCD2 score is inaccurate as a predictor of imminent stroke. The cut-off of 4 was not particularly sensitive or specific in this large prospective study.

 

 

Notes: It seems as though national guidelines are slowly being updated as a result of this study (and others)...

 

 

"Patients with suspected TIA should have a full diagnostic assessment urgently without further risk stratification." (Royal College of Physicians (2016)

 

 

"If a person has had a suspected TIA within the last week, give aspirin 300mg immediately and arrange urgent assessment (within 24 hours) by a specialist stroke physician... Discuss the need for admission if the person has had more than one suspected TIA or they may be unable to attend." (NICE Clinical Knowledge Summary, updated 2017)

 

 

Risk stratification should be based on clinical features only... High-risk symptoms are unilateral motor weakness or speech disturbance; moderate-risk symptoms are unilateral sensory changes, painless visual loss, diplopia or ataxia (paraphrased from the Canadian Association of Emergency Physicians Stroke Best Practice Recommendations 2018)

 

March 16th, 2019    

42. Are steroids effective for acute gout?

Background: The two medicines recommended by NICE for acute gout are NSAIDs and colchicine. The main problem with NSAIDs is that they are contraindicated in many patient groups - the elderly, those with bleeding disorders, stomach ulcers, renal insufficiency and liver dysfunction to name a few. Colchicine is not always a great choice either, frequently causing diarrhoea. I've had patients come into the room saying, "Don't prescribe that medicine that gives me the s**ts!"... Is there another option?

 

Billy CA, Lim RT, Ruospo M, et al. Corticosteroid or nonsteroidal antiinflammatory drugs for the treatment of acute gout: a systematic review of randomized controlled trials. J Rheumatol. 2018;45:128-136

 

The paper: A systematic review that found 6 RCTs comparing steroid to NSAIDs for the treatment of acute gout. These trials covered a total of 817 patients. They found no significant difference between the two drugs in terms of pain relief, time to resolution of pain, or requirement for additional analgesics. There was also no difference in rates of GI bleeding, although nausea, vomiting and indigestion were commoner in the NSAID group. Hyperglycaemia was commoner in the steroid group.

 

The bottom line: This review found no significant difference between steroids and NSAIDs for acute gout, though they did see more side effects with NSAIDs. Steroids seem to be a reasonable treatment choice, unless your patient is diabetic.

 

Note: the most common dosing regimen for steroids in the studies was oral prednisolone 30mg daily for 5 days

 

Expert commentary:
"Please also be aware that prednisolone is a risk factor for and can trigger peptic ulcers."

(Dr Robert Tan, ED consultant)

March 11th, 2019    

41. When can traumatic lacerations be closed?

 

Background: When are you happy to suture a traumatic laceration closed? 6 hours? 12? Longer? The 'Golden Period' used to be 6 hours, but many clinicians have moved away from this, particularly for wounds on the face or neck. A literature search of this topic turns up many papers, but most are quite small, observational and retrospective in approach. Still, the collective force of these has been to push back the 'golden period' beyond 6 hours, but no one really knows what the magic number should be. What we are most interested in, of course, is the risk of infection. This paper has some answers for us.

 

Quinn JV, Polevoi SK, Kohn MA. Traumatic lacerations: what are the risks for infection and has the 'golden period' of laceration care disappeared? Emerg Med J. 2014;31(2):96-100.

 

 

The paper: This was the largest multicentre prospective cohort study of consecutive lacerations in the ED. From an initial group of 3,957, a total of 2,663 patients completed follow up (which is pretty good for a wound care study). In each case, data on 27 variables were collected at the time of treatment. The patients were reviewed or spoken to after 30 days to determine whether an infection had developed and whether they were happy with the cosmetic result. The authors suggested that it would become cost effective to give prophylactic antibiotics when there was a greater than 5% chance of infection. Those variables associated with a significantly increased infection rate (>5%) were diabetes, lower extremity lacerations, contaminated wounds and lacerations greater than 5cm. Interestingly, time from injury to wound closure made no difference to infection rate in this study (3% if under 12 hours, 1.2% if over 12 hours - numbers were not sufficiently high to make this significant).

 

The bottom line: This large study found no evidence that closing older wounds increases the risk of infection. Infections were commoner in diabetic patients, those with leg wounds, large wounds (>5cm) and contaminated wounds.

 

Expert commentary:
"This is useful and hopefully diminishes the incorrect belief that antibiotics are always required - they should be prescribed only to high risk patients or for high risk wounds. Also, giving antibiotics should not replace proper cleaning and if required debridement (to fresh edges) of the wound."

(Dr Dwynwen Roberts, ED consultant)

 

March 5th, 2019    

40. Steroids for viral-induced wheeze?

Background: The use of steroids in preschool children with a viral-induced wheeze is a bit of a grey area. Our local protocols are silent on the issue, and I know that paediatricians differ in their approach. A large RCT by Panickar et al in 2009 found no difference in any clinically relevant outcome between prednisolone and placebo, but this study has been criticised for including children as young as 10 months, many of whom were likely to have had bronchiolitis. The current study directly addresses the issue of age and seeks to clarify this ongoing question.

 

The paper: A single-centre RCT involving 605 children aged 2-6 years old who presented to the ED with wheeze and symptoms or signs of a viral URTI. There was a range of severity represented in the study (assessed using the Pulmonary Score, which is similar to the Paediatric Asthma Score but briefer and not yet validated). However, children with oxygen saturations <92%, cardiac disease or prematurity were excluded. Half were given prednisolone and half placebo. The primary outcome was length of hospital stay, while secondary outcomes included reattendance, readmission and salbutamol usage. There were no differences in any of the secondary outcomes, but median length of stay was significantly shorter in the prednisolone group (6hr vs 9hr with placebo). Subgroup analysis showed that prednisolone was most effective in those with severe symptoms (pulmonary score >5), where median length of stay was 5 hours shorter than placebo (10hr vs 15hr). Interestingly, family or personal history of atopy did not affect outcomes in this study. (The Lancet Respiratory Medicine, January 2018)

 

The bottom line: This study provides some evidence that prednisolone is effective at reducing the symptoms of viral-induced wheeze in children aged 2-6.

 

Note: SIGN guideline 153 (the Scottish Intercollegiate Guidelines Network, for the uninitiated), written in conjunction with the British Thoracic Society in 2016, recommends oral steroids for preschool children with moderate or severe wheeze, but cautions against prescribing multiple courses in children with frequent episodes.

 

Expert commentary:
“In this study giving prednisolone only reduced hospital stay by 3 hours, so for for children who are well enough to go home the benefits of steroids do not outweigh the risks. After reading this paper I personally prescribe steroids only to those who have severe wheeze or have a strong personal or family background of atopy – 3 hours less in hospital does not seem worth it!”

(Dr Emily Goodlad, Paediatric consultant)

 

Expert commentary:
“The younger the child, the more cautious you have to be about prescribing steroids. Personally, I only give prednisolone to children aged 1-2 if I’m happy they don’t have bronchiolitis and they have shown a clear improvement with salbutamol (but are still struggling a little).”

(Dr Mohsin Jafri, Paediatric Consultant)

 

Note: Please see also this post in The BREACH from August on dexamethasone vs prednisolone for asthma exacerbations in children

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