Wednesday 1 March 2017

Neck Pain and Ice



I taught my first aid team how to take a history the other day and as I did so a little shockwave of warmth and contentment ran through me. You see, history taking is a game that patients like to play with doctors where we try to garner enough information to establish a diagnosis and patients do their best to obstruct that process.

Me: So, Mr X, how long have you had this pain in the neck?

MR X: Oh, a while.

Me: I see. Erm...any idea how long “a while” is? Are we talking weeks, months, years?

Mr X: Well, it started after I bought the new playstation.

Me: Riiiiiiight....I’m not quite sure when that was, Mr X.

Mr X: Well, you know, just after the TV.

Me giving up: OK, fine, fine. So what does the pain feel like, Mr X?

Mr X: Well, you know, it’s bad. Really sore.

Me: OK, yes, but you know how a burning pain is different to say, a stabbing pain? Which is different to an ache? Well, what does the pain feel like? Because that might help me to differentiate what the problem is.

Mr X: Well, it’s just bad really.

Me getting slightly high pitched: So I get that the pain is severe, but what I’m really trying to get at Mr X, is what the sensation feels like.

Mr X: Oh I see. Well it’s like a burning, stabbing, achey kind of pain really.

Mr X, this last in a helpful voice: But it’s really bad. Very sore.

Me: So, Mr X, do you have any previous medical complaints?

Mr X: No, none.

Me, nearly crying now: Are you quite, quite sure Mr X? Any idea why you might be on this cornucopia of medication then?

Now, I don’t want you to get the impression that doctors are impatient and intolerant individuals who bark questions at their patients and are never satisfied with the answers. No, indeed. We’re all lovely people. I, in fact, have a certificate of niceness! But the above conversation is one that will definitely be familiar to all of my colleagues so it was with a sweet sense of recognition that I saw very similar interactions being played out by my first aid team.

I had split the team in half and given one set of first aiders the scenarios and the others were to try and take a history from them using the SAMPLE (symptoms, allergies, medications, past medical history, last oral intake, events leading up to illness)  framework. It was so satisfying. I watched my first aiders struggling to gain the correct information from patients who decided entirely without prompting to be obstructive and withhold key nuggets of information. Perhaps my favourite moment was when I took on the role of the consultant on a post-take wardround (the consultant who reviews patients after admission and clerking by a junior doctor) and had various angry first aiders squawk, “Hey, you told me you had a pain in the neck, not in the buttock!” Welcome to hospital medicine lads. Welcome.

Joking aside, my first aid team are doing brilliantly. We’ve covered using splints, taking X-rays, history taking, wound and burn management, major trauma, managing severe allergies, and hypothermia and cold related injuries. I couldn’t be more pleased with them. But I wouldn’t be human if I hadn’t experienced a flicker of schadenfreude during the history taking...

That rather bold interlude aside, let’s talk about ice. As, I’m sure you’re aware, ice is the solid form of water. And as anyone who has ever had an iced drink will know, ice floats on top of water.




 Now this happens because ice is rather less dense than water and so it’s able to float. Think of water molecules as square dancers interacting with each other. In liquid water the music is playing and the dancers are gliding past each other, swinging their partners round and stripping the willow with glee. In ice, the music hasn’t started just yet so the dancers remain at a fixed distance from each other and they don’t move.


So what makes our icy square dancers so stand-offish? Well, water molecules have something called hydrogen bonds holding them together. In liquid water the hydrogen bonds are constantly breaking up and reforming, rather like our square dancers taking new partners. As water gets warmer, the particles within it have more energy so they move about more and break and remake the hydrogen bonds more frequently. The reverse happens as water gets colder. As water turns to ice, the water molecules stop moving about and stay still. The hydrogen bonds within the ice stop breaking and reforming and instead are fixed- just like the dancers when the music stops. Because the hydrogen bonds aren’t continually breaking and reforming, the water molecules are forced away from each other by the fixed and outstretched hydrogen bonds and thus the liquid water is denser than the ice because the molecules in liquid water can get closer together.

Now this is quite handy. If ice was denser than water it would sink to the bottom of our oceans and seas and these bodies of water would freeze from the bottom up. This would be rather a shame for all of the organisms that dwell at the bottom of our seas but it wouldn’t just be those organisms that suffered. Some scientists hypothesise that were the seas and oceans to freeze, they would reflect solar heat back out into space and in very little time our lovely home would turn into a massive ice ball.

The other rather nifty trait of ice is that it’s transparent. Light passes through ice to illuminate the water beneath. This enables photosynthesising organisms to make their home under the sea ice down here in the Southern Ocean whilst being protected from the wrath of the elements by the carapace of ice. The algae and young krill that live under the sea ice are a vital part of the food web of the Southern Ocean- without the sea ice these food webs could start to come apart and the cute little weddell seals and penguins might start to struggle.


Emperor Penguins



Emperor Penguins in the water


Now, you may wonder why the fate of a weddell seal is even remotely important to you. After all, that seal is a long, long way away. It never calls on your birthday and it certainly never sends you a Christmas card. All it does, in fact, is help to trap carbon that was in the atmosphere in its own body. Our friend the seal eats the krill, which feeds on the algae which strips carbon dioxide from the atmosphere. The southern ocean is a carbon sink of incredible importance and without the ice it might not do its job as well as it does. So if you’re opening a bottle of wine tonight, or perhaps enjoying a gin and tonic, I’d like you to raise your glass to the ice. Saving our planet, one cube at a time!

7 comments:

  1. Hi Helen,

    You say that if the ice sank, our oceans would freeze from the bottom up. If that's true, why don't they currently freeze from the top down?

    ReplyDelete
    Replies
    1. Hey, good question! So I have discussed with our resident oceanographer and apparently the answer is that ice is a very good insulator. So ice protects the water from the extreme cold of the air temperature and helps it to conserve heat in the water below the level of the ice. Does that make sense? Hx

      Delete
    2. Yes, it does. It's good to learn!

      Julia

      Delete
  2. Helen you should be an earth scientist 😊😊

    ReplyDelete
  3. Helen you should be an earth scientist 😊😊

    ReplyDelete
    Replies
    1. Thank you very much. I do love a bit of science. And it's forcing me to remember my school Chemistry and Physics lessons which is great!

      Delete
  4. Hi Helen, I'm a medical student at university of Nottingham and was wondering if you had a contact email address? I would love to get in touch regarding your work!

    ReplyDelete