December 27, 2014

2014: Year In Review

I had a great time writing blog posts this year.  In 2014, there were 52 posts put up on the blog (not counting this one).  Maybe there are some that you missed, or need to find again. 

The most popular posts:
1. Chuck Yeager Voice - this one almost doubled the page views of second place...
2. MRSA is not a river in Africa
3. Giving NTG to an Inferior MI.  People still think I’m a maniac for my point of view on this one… (The first part of that topic is a scenario.)

Speaking of stuff I hate besides adenosine, there are also articles about Peroxide, Rats, and the term “Sober and Competent” (plus Part II).

I shared a few stories about my egregious mistakes and bad habits, hopefully to stop you from doing the same dumb things.  They include vicious, wild Three-Legged Labs, the story of the guy who was Shot in the Calf, why I stopped Wearing Uniforms Home, and why I need to stop Prejudging Calls.  There are also stories of Medics Getting Hurt, evil medication Ampules, and another story of another guy who was Shot in the Groin without getting a hole in his pants.

I try to orient my posts to prehospital knowledge: skills and information that a medic needs but that a doctor or nurse wouldn’t need (as much).  Even so, there are topics that I think prehospital personnel don’t have a firm grasp of.  So I’ve written posts about why Pancreatitis should be treated better, the different kinds of Aphasias, Leadership Traits, how ECG Filters work, my opinion of How a 12-Lead Should Be Laid Out, a discussion of Rare Syncope Causes, why I think the phrase ‘Children Aren't Little Adults’ is trite and meaningless, and my thoughts on when patients are Fakers/Malingerers.  There are posts about what I think are the prehospital world’s Good Journals and Blogs, basic Ethics, Three Reasons for Noncompliance among your subordinates, and the importance of being in a career that requires Expertise.

But I really like to focus on prehospital skills.  So I talked about Establishing Good Habits, Making Decisions in Advance, with Part II, and a post about communication that could have been called Don't Tell Me Your Problems; Tell Me What You Want.  I talked about how history taking is kind of like a Tree of Knowledge, the Power of WTF, my feeling on Family Riders (TL;DR is NO), my thoughts on Field Training, and even whether it makes sense to make Left and Right Turns.  I posted about how to give Big Room Reports, Telling Family Grandpa is Dead, and the prevalence of Acting in EMS (at least on my ambulance).  Other posts include What Equipment to Bring into a call, how to handle Advance Directives (we do really bad at this), different stages of Agitation, and the first Five Actions on an MCI.  Going on, we discussed Bulletproof Vests (I’m not a fan), the reasons for Single Car Crashes, why I hate approaching Slumper Cars, and how to write Narratives.  Finally, I also gave my untested idea about Distracting Injuries, ranted about Giving Your Expert Opinion, and the fact that I can’t do anything about Bumsicles.

By the way, in the interest of balance, the least read posts of 2014 were:
     51. Expertise
They aren’t bad, especially the expert opinion and advance directive posts.  You should take a minute and read them…


Have a good one, and a better 2015.  Happy New Year.
Try to keep your NYE party under control...
(By Bird33ou [Public domain], via Wikimedia Commons)

December 20, 2014

I Hate H2O2 (Sometimes)

I was working special event duty this weekend.  A lady presented to the first aid room after a minor fall onto concrete.  She abraded her knees, fairly deeply.  Some of the abrasion could even be described as lacerations.  One of the other medics jumped to it.  He busted open a bottle of 3% hydrogen peroxide, poured it over the lady’s knee wounds, dried it all with a 4x4, and bandaged it all up.

Did he do the right thing for that patient?
I need to put this here so that the next pic isn't the one that constantly shows...
Hydrogen peroxide (H2O2) was used as an antiseptic in this case.  The difference between an antiseptic and an antibiotic is that an antibiotic is usually directed at killing specific bacteria.  An antiseptic is designed to kill or impede most microorganisms – bacteria, fungi, and viruses.  Several antiseptic categories exist, but common ones are alcohols (ethanol), biguanides (chlorhexidine), bisphenols (triclosan), chlorine compounds, iodine compounds, and hydrogen peroxide.  One of the most common antiseptic soaps uses triclosan.  When you swipe an alcohol prep or iodine prep on an arm, you’re using the alcohol as an antiseptic.

Those antiseptics are used externally, though.  Most aren’t designed to be poured into an open wound.  What if an antiseptic kills bacteria, but it also kills human skin cells?  Are there studies that can help us?

In lab conditions, hydrogen peroxide appears to work to kill bacteria.  It works best on Gram-positive bacteria, but when catalase is present (like in living tissue), hydrogen peroxide becomes less effective.(1, 2)  Some studies did not find that hydrogen peroxide messes with wound healing.  For example, Gruber’s group (3) found that peroxide lengthened the healing time of wounds.  This is probably because bullae formed in the wounds, suggesting that hydrogen peroxide should be avoided with new epithelium.  Lineaweaver, et al.,(4) found that wound healing was not inhibited in rats, but this study also found that microorganism load didn’t change a whole lot, either.  Two other studies did not show that hydrogen peroxide was effective as an antiseptic.(5, 6)  One final study on fetal tissue indicates that hydrogen peroxide may increase scarring (7).

So, in short, hydrogen peroxide does not appear to work well as an antiseptic.  This makes sense when you think about it – its not like surgeons pour 3% hydrogen peroxide over incisions, right?  Ever seen an ED physician pour a bottle of peroxide into a laceration before s/he sutures it up?  Nope.  They use clean water irrigation to clean wounds.
"Uh, yeah.  I'm going to need about 15 gallons of hydrogen peroxide, STAT!"
Shotgun wound by DiverDave (Own work) [CC BY-SA 3.0], via Wikimedia Commons

In addition, there seems to be some questions as to whether H2O2 affects wound healing or not.  It appears to be cytotoxic.  So if there is questionable efficacy, plus controversy regarding healing rates, why use it?

Use soap and water.  Copious irrigation with clear water.


For me, hydrogen peroxide is really good for one thing – loosening dried blood, especially on equipment and white shirts.  There are calls after which I pour a bottle of peroxide all over the pram.  The bubbles show where the blood is, plus loosens it up so I don’t have to scrub it off as extensively.  It seems to really help in tight little seams and other hard to reach places.  I also use it to loosen up blood stains on a white shirt.  I’ve not had a shirt ruined since starting to dab with peroxide.



1. Brown CD, Zitelli JA. A review of topical agents for wounds and methods of wounding. J Dermatol Surg Oncol 1993;19:732-7.
2. McDonnell G, Russell AD. Antiseptics and disinfectants: Activity, action and resistance. Clinical Microbiology Reviews 1999;12(1):147-79.
3. Gruber RP, Vistnes L, Pardoe R. The effect of commonly used antiseptics on wound healing. Plast Reconstr Surg 1975;55(4):472-6.
4. Lineaweaver W, Howard R, Soucy D, et al. Topical antimicrobial toxicity. Arch Surg 1985;120(3):267-70.
5. Leyden JJ, Bartelt NM. Comparison of topical antibiotic ointments, a wound protectant and antiseptics in the treatment of human blister wounds contaminated with Staphylococcus aureus. J Fam Pract 1987;24(6):601-4.
6. Lau WY, Wong SH. Randomised, prospective trial of topical hydrogen peroxide in appendectomy wound infection. Am J Surg 1981;142:393-7.
7. Wilgus TA, Bergdall VK, Dipietro LA, Oberyszyn TM. Hydrogen peroxide disrupts scarless fetal wound repair. Wound Repair Regen  2005;13(5): 513–9. 

December 6, 2014

Expertise

I’m kind of an amateur dinosaur nerd.  What can I say, I’ve liked paleontology since I was a kid.  Anyway, I was surfing through some paleontology blogs, as I have been known to do on a Saturday, and found a post about a paleontologist who was sorting through bones in Ottawa’s Canadian Museum of Nature.  Mental Floss had the story, also. Without getting deep into Mesozoic detail, the bones were classified as two genera similar to triceratops.  The paleontologist, Dr Nick Longrich, reanalyzed the bone fragments and decided that they were actually two different genera of Canadian dinosaurs that were previously believed to only come from the American southwest.*
There are apparently blatantly obvious differences between all of these animals...
Ceratopsidae Skulls, to Scale by Danny Cicchetti (Own work) [CC-BY-SA-3.0], via Wikimedia Commons    
It isn’t all that uncommon for something like that to happen.  Here is another post where a PhD student stumbled upon a previously undescribed sauropod (long neck big dinosaur) genus sitting in a box in London’s Natural History Museum.

I don’t actually know a lot about classifying fossils.  It seems incredible to me that an expert can look at the curve of a bone, or the shape of an opening on a bone fragment, and know that they are holding a new genus of dinosaur.  Think about the time one has to spend, the investment in knowledge, and the experience level needed to be able to do that.  That is an incredible amount of deep, deep expertise needed for that job.  You also hear about this kind of expertise in relation to art appraisal, where an expert can look at details and name the artist – based on friggin’ brush stroke patterns.  Pilots can feel something wrong with their aircraft, based on how it is handling at that moment, in those conditions. 

I wish I had a job like that where expertise is necessary.

Oh, wait.  I do.

I can tell sick-not-sick in a glance from a dozen feet away from a patient.  I can tell, with reasonable accuracy, what kind of call I am going on based on the address and time of day.  I know what particular streets offer for traffic patterns at different times.  I know the interiors of a hundred different buildings, and the best place to access each.  I know how to bring the calm to the chaos.  I know how to intubate a person at floor level in a dark, dirty, cramped room.  I can tell the difference between sinus and AFib at a glance.  I can look at a pile of medications, know what they were prescribed for, and know which the patient hasn’t been taking.  I know my way around the intestinal underground tunnels of stadiums, airports, and other big buildings.  I know if that family member right there is going to be a problem.  I can listen to breath sounds, watch a patient breathe, and feel a pulse to generally know if the patient will need their breathing to be assisted on the way to the hospital.  I know whether it is worthwhile to start an IV in the car, or wait til after extrication.  I have a sense of who needs restrained before anything even happens.  I know the right way to cut a down coat (get it wet first, so the down doesn't explode everywhere).  I know when a house is dangerous.  I know how to calm a frightened child.  I know how to calm a frightened adult.  I know how to give a biophone report so as to get what I want.  I know how to communicate with a team of providers and other personnel to manage emergencies.  I know how to manage an MCI. 

What things do you know?


*A link to find the published paper is here.