Maybe clothing technology really hasn’t gotten better

Early in the 20th century, explorers were busy trying to reach the poles and climbing mountains, simply because they were there. The casual observer from modern times must wonder how they were able to tolerate such cold temperatures without the high-tech fabrics available today. The mental images of Amundsen, Scott, Peary, and other cold weather explorers are often viewed as men laden with incredibly bulky furs and wool garments. How on earth could they achieve anything wearing that kind of clothing?

Credit: National Geographic/The Wildest DreamThat question has particular merit when considering the legacy of George Mallory and Andrew Irvine. They died in 1924 while attempting to summit Mt. Everest, almost 3 decades before Hillary and Norgay were able to do it successfully. Mallory’s remains were found in 1999 at 8157m, and his clothing was removed for testing before he was buried. After 3 years of intense study using multiple methods, they were finally able to definitively say what he was wearing.

But that only answers part of the question. Now that we know what he was wearing, was it enough to keep him warm but still allow freedom of movement needed to climb mountains? To test this, they simply replicated the fabrics, which were layers of silk, cotton, and wool. This was then covered with an outer layer of gabardine, faithful to the original made by Burberry.

(As an aside, many readers may not be aware of Burberry’s prowess in making clothing for polar expeditions. Like Abercrombie and Fitch, the clothing you can buy today is nothing in comparison to the rugged outdoor items one used to be able to purchase.)

So with that part answered, all that was left was for someone to climb Everest wearing the replica clothing. And Graham Hoyland did just that in 2006. He didn’t summit, but he did learn that the fabrics were light, comfortable, and more importantly, warm enough to use during the day. They were not, however, thick enough to survive a bivouac on the mountain in his opinion.

The part that made the outfit ingenious was the different fabrics of the alternating layers. This allowed decreased the friction between the layers, allowing movement with much less energy expenditure. This was demonstrated when tests comparing Scott’s to Amundsen’s layered garments showed a 20% decrease in said energy doing the same activity when more “slippery” fabrics were used (silk and furs versus wools). The same scientist also showed that Mallory’s fabrics would have been able to protect all the way down to -30C in calm weather.

Sadly, calm weather they did not have. A blizzard came upon them as they approached the summit, and they were last seen on one of the Three Steps. Whether this storm made them turn back or not, it certainly would have predisposed them to hypothermia. As to whether Mallory and Irvine actually summitted? We may never know, unless someone finds Howard Somervell’s camera with proof.

While these findings have done away with the myth that Mallory’s expedition was ill-prepared (based on photos from base camp), what they really show is that modern synthetic fabrics have only incrementally made gains in thermal protection, weight, and function. The argument can be made that tailoring them to fit properly is as important as the material itself.

I wouldn’t try to climb Everest in any modern garment made by Abercrombie or Burberry though.

Mountain Clothing and Thermoregulation: A Look Back
http://www.ncbi.nlm.nih.gov/pubmed/22441098

Additional Readings
http://www.alpinejournal.org.uk/Contents/Contents_2007_files/AJ%202007%20243-246%20Hoyland%20Clothing.pdf
http://www.independent.co.uk/news/world/asia/mystery-at-the-top-of-the-world-did-george-mallory-make-it-to-the-summit-of-everest-before-he-died-2063196.html
http://news.bbc.co.uk/2/hi/science/nature/5076634.stm
https://dspace.lboro.ac.uk/dspace-jspui/handle/2134/9716
http://thewildestdream.com/

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More Discharges With HEART

Although, the observed improvements are probably more a result of their preposterously high initial admit rate.

The HEART score, already evangelized in multiple venues, is a tool for risk-stratifying chest pain patients in the Emergency Department.  Its advantage over other, competing scores such as GRACE and TIMI, is its specific derivation intended for use in the Emergency Department.  This trial, of note, is one of the first to do more than just observationally report on its effectiveness.  These authors randomized patients to the “HEART Pathway” or “usual care”.  The HEART Pathway was a local decision aid, combining the HEART score and 0- and 3-hour troponin measurements.  Patients with low-risk HEART scores (0 to 3) were further recommended to treating clinicians for discharge from the Emergency Department without additional testing.  The primary outcome was rate of objective cardiac testing, along with other secondary outcomes related to resource utilization.  Patients were also followed for 30-day MACE, with typical endpoints for cardiovascular follow-up.

With 141 patients each arm, the cohorts were generally well-balanced – specifically with regard to TIMI score >1 and accepted cardiovascular comorbidities.  Stunningly, 78% of the usual care cohort was hospitalized at the index visit.  Thus, the mere 60% hospitalized in the HEART pathway represented a massive improvement – and, such difference likely played a role in the 57% vs. 68% reduction in objective cardiac testing within 30 days.  17 patients suffered MACE, all at the index visit – and, even though the trial was not powered for safety outcomes, none occurred in the “low risk” patients of the HEART cohort.

The authors go on to state strict adherence to the HEART pathway could have eked out an additional 6% reduction in hospitalization.  Certainly, in a nearly 80% admit rate environment, scaling back to a 54% rate is an important reduction.  But, considering only 6% suffered an adjudicated MACE, there remains a vast gulf between the number hospitalized and the number helped.  Some non-MACE patients probably derived some benefit from their extended healthcare encounter as a result of better-tailored medical management, or detection of alternate diagnoses, but clearly, we can do better.

“The HEART Pathway Randomized Trial – Identifying Emergency Department Patients With Acute Chest Pain for Early Discharge”

Fracture Fridays: Three Planes (re-post)

The case

A 15 year old skateboarder totally screws up a rail grind. After posting his wipeout to YouTube his friends call his mom, who notices that he has been unable to walk on his ankle – probably because of how ridiculously swollen it is.

swollen ankle

A gnarly swollen ankle

You get an XRay, because that’s what you do…

Ankle XRay

The ankle X-Ray you just got

The Diagnosis

Hmm, doesn’t look that bad right? Right? OK, this is an educational blog, so yes, it is bad. This is a big deal fracture. In fact it is a Salter-Harris IV fracture of the distal tibia. AKA the dreaded Triplane Fracture.

The fracture plane of this triplane fracture

The fracture plane of this triplane fracture

Why is it so bad? Well, aside from being accountable for 10% of the intra-articular ankle fractures in patients with open physes. Boys predominate, probably because they like to do things like rail grind on their skateboards. The peak age is 12-15 years. The fracture itself involves three planes:

  • Transverse through the physis
  • Sagittal through the epiphysis
  • Coronal through the distal tibial metaphysis

This diagram may help.

3D representation of the planes of the triplane fracture

3D representation of the planes of the triplane fracture

The main concern is not growth arrest, but rather the stability of the articular surface itself. That should lead you to assume (correctly) that these fractures generally need to be stabilized in the OR. More on that in a minute (of your reading time).

Management

As you can see from the initial X-Ray the initial findings are not 100% obvious in many cases. However it is still important to get them first (after applying the Ottawa ankle rules of course) as is a high level of association with concomitant fibula fractures. Normal ankle X-Rays show the ‘telephone’ sign, where the tibia and fibula (the handset) sit above the talus (the telephone base).

A normal looking ankle X-Ray

A normal looking ankle X-Ray

Asymmetry, and disruption to this normal orientation suggests a fracture. This is one fracture where a CT scan can be helpful, especially with the new 3D reconstruction modalities. Establishing the plane of disruption can be very helpful for your orthopedic colleagues.

Standard CT views in a triplane fracture

Standard CT views in a triplane fracture

A really cool 3D reconstruction of a triplane fracture

A really cool 3D reconstruction of a triplane fracture

In general orthopedists will first pursue closed reduction. Then, if a residual fracture gap of >2 mm exists surgical fixation is generally necessary. The likelihood of successful closed reduction (without need for surgery) is actually more likely if there is >3 mm of displacement initially. That doesn’t mean that you don’t have a role in the ED. Ater a careful neurovascular assessment you can provide pain medicines (these hurt quite a bit) and if transfer to another facility is warranted, place a posterior splint. These fractures should be seen urgently (within 24 hours) by an orthopedist.

For more information check out:

Ortho Bullets – Triplane Fractures

eMedicine – Triplane Fractures

Analysis of tibial fracture CTs

The post Fracture Fridays: Three Planes (re-post) appeared first on PEM Blog.

John Hinds on Airway at #RCEMBelfast

Screen Shot 2015-03-27 at 10.17.15

We managed to grab John Hinds after his fantastic talk on airway management in the ED at the RCEM Spring CPD conference.

At a time in which EM is establishing its position in airway management and developing strategies to advance care for patients in the Resuscitation room John gave us some fantastic advice on his approach to RSI. He talked about establishing strong working with Anaesthetics and ITU and working together to promote best patient care.

There were loads of take home messages including the importance of an RSI checklist (every time), issues around drugs choices for RSI and not only having a plan for the can’t intubate can’t ventilate scenario but most importantly ensuring it can be implemented swiftly and effectively.

Enjoy the podcast!

 

Osteosarcoma

Osteosarcoma

We all know that when you “hear hoofbeats, think of horses” and when you “see stripes, think of zebras.”  Unfortunately, the horses and zebras often look similar.  While tachypnea is most often due to a viral process like Bronchiolitis, or a Pneumonia, we must stay vigilant for it being one of those Subtle Signs of Heart Failure.  Keeping a keen eye and ear on alert for these zebras is part of what our job demands.  A child presenting with Back Pain should catch your attention just like a the child complaining of persistent leg pain.  While it is most likely innocuous, it could also be a zebra getting ready to stampede: Osteosarcoma.

 

Osteosarcoma: Basics

  • In the USA, cancer is the second leading cause of death in children.
    • Leukemia leads all other cancers – ~50 per 1,000,000 (CDC Stats)
    • Osteosarcoma incidence – ~5 per 1,000,000 (CDC Stats)
  • Osteosarcoma is the most common primary bone tumor in patients < 40 years of age. (Haddox, 2015)
    • Other important primary bone tumors = Ewing and Chondrosarcomas
  • High rates of metastasis.
  • Vast majority of osteosarcomas in children are High Grade. (Gorlick, 2010)
  • Survival has improved with advances in surgical, chemotherapeutic, and radiation care.
    • Before 1970’s, 5-year survival was < 20%.
    • Now it approaches 70%.
    • Generally, children have a better prognosis compared to patients 18-40 years of age. (Haddox, 2015)

 

Osteosarcoma: Presentation

  • Peak frequency = onset of puberty
  • Location:
    • Most arise in the intramedullary space of the metaphysis. (Gorlick, 2010)
      • Most often in the long bones of the lower extremities.
      • ~50% involve the knee (Distal Femur and Proximal Tibia)
      • Proximal Humerus is next most common site.
    • Possible relationship with Growth Plates.
    • In older pts, it is more common in the axial skeleton.
      • Spine involvement only in 4-5% of cases.
  • Primary complaint = Pain.
    • Often insidious
    • Pain with activity is most common complaint.
      • Just like everything else that hurts… it hurts more when you use it.
      • Growing Pains” is often the original misdiagnosis.
    • May present with limp due to pain.
    • Larger lesions may present with palpable mass.
    • Uncommon to have night sweats, fever, or other systemic symptoms initially.
    • Pathologic Fracture (Lee, 2013)
      • Can cause the initial presentation (5 – 12%)
      • Can also develop during treatment
      • Associated with poorer prognosis.
  • Appearance on Radiographs
    • Lytic and blastic bone lesion
    • “Sunburst” appearance
    • Periosteal elevation related to soft tissue mass producing “Codman’s Triangle.” (Gorlick, 2010)
  • Metastasizes to the Lungs and other Bones primarily.

 

So the next time you see the pre-teen who is complaining of knee pain after running in gym and you really want to blame “growing pains” or a minor strain… just pause and consider that those hoofbeats you hear are actually those of the stampeding Osteosarcoma Zebra.

 

References

Haddox CL1, Han G2, Anijar L1, Binitie O3, Letson GD4, Bui MM5, Reed DR3. Osteosarcoma in pediatric patients and young adults: a single institution retrospective review of presentation, therapy, and outcome. Sarcoma. 2014;2014:402509. PMID: 24976784. [PubMed] [Read by QxMD]

Vijayakumar V1, Lowery R1, Zhang X1, Hicks C1, Rezeanu L1, Barr J1, Giles H1, Vijayakumar S1, Megason G1. Pediatric osteosarcoma: a single institution’s experience. South Med J. 2014 Nov;107(11):671-5. PMID: 25365431. [PubMed] [Read by QxMD]

Botter SM1, Neri D2, Fuchs B3. Recent advances in osteosarcoma. Curr Opin Pharmacol. 2014 Jun;16:15-23. PMID: 24632219. [PubMed] [Read by QxMD]

Lee RK1, Chu WC, Leung JH, Cheng FW, Li CK. Pathological fracture as the presenting feature in pediatric osteosarcoma. Pediatr Blood Cancer. 2013 Jul;60(7):1118-21. PMID: 23281226. [PubMed] [Read by QxMD]

Kim HJ1, McLawhorn AS, Goldstein MJ, Boland PJ. Malignant osseous tumors of the pediatric spine. J Am Acad Orthop Surg. 2012 Oct;20(10):646-56. PMID: 23027694. [PubMed] [Read by QxMD]

Gorlick R1, Khanna C. Osteosarcoma. J Bone Miner Res. 2010 Apr;25(4):683-91. PMID: 20205169. [PubMed] [Read by QxMD]

The post Osteosarcoma appeared first on Pediatric EM Morsels.

Sesiones de los PAC: Convulsiones en pediatría

Nuestra sesión del mes de marzo nos la ha ofrecido Aitor Larramendi, médico del PAC de Iztieta y ha tratado sobre las convulsiones en los niños; un tema que, afortunadamente, no vemos a menudo pero que cuando nos toca nos genera bastante agobio. Aitor nos ha hecho un buen repaso sobre las causas más frecuentes atendiendo a la edad del paciente pediátrico y uno todavía mejor sobre su tratamiento en nuestro ámbito. Yo creo que nos puede resultar muy útil. Además, os adelanto que volverá en breve con alguna otra cosa bien interesante también relacionado con nuestros pacientes más pequeños...¡es que la pediatría sí que es el pan nuestro de cada día!
Mila esker, Aitor!