Sunday 24 November 2013

Stomachs in Reverse

Most of last week Beans and Bunny were not outside. Beans and Bunny were inside. Throwing up. The girls have recently been struck by stomach viruses. The dreaded "tummy bug". Bunny went first, throwing up on the walk to school. Then Beans a few days later, as we stood getting her hockey equipment out of the van in the arena parking lot. All over her rainboots (I know, thankfully she was wearing rainboots!). I used her water bottle to wash her off because clearly we weren't going to be using it for hockey that day. As a bonus we got to talk about scavengers again because the Ring-billed Gulls came to eat the eggs and toast that were now all over the lot.

This prompted a discussion between Bunny and I about viruses in general and her body's defenses against them. There's a few different tactics based on the type of virus - sometimes it's runny nose and coughing and sometimes it's vomiting (and we've been through them all) - for your body to try to rid itself of the virus. But what Bunny was really interested in was more the how - if food is supposed to go through your digestive system in a downward fashion, why does it all of a sudden go the other way and how is it doing that?

So, vomiting, throwing up, puking, blowing chunks (technically emesis) - is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. (Thanks wikipedia). And there's a ton of underlying reasons why it happens but regardless of the why, how the event itself happens is pretty consistent.

Your brain has a "vomit trigger" zone. It's in the fourth ventricle of your brain and is called the area postrema. The stimulation of this zone, by various methods, is what causes your body to start the expulsion routine.

These are from Gray's Anatomy (the book, not the show):
 

So there's a few ways to get this party started (although often this kind of ends the party) through chemoreceptors and that can be through blood-borne toxins and drugs, the vestibular system (which we talked about with motion sickness), cranial nerves through your pharynx (gag reflex), central nervous system (stress and psychiatric issues) and the enteric nervous system which tells your brain about the state of your gastrointestinal (GI) system. For Beans and Bunny it was that last one - irritation of the GI system through a viral infection - gastroenteritis, our tummy bug.

Once it's triggered it sends messages out to the rest of the body on how to react which results your body prepping itself for the big show - this happens quickly and gives you that "oh no, I'm going to puke" feeling. An amazing number of things happen simultaneously - you produce more saliva to protect your teeth from stomach acid, your lungs fill so that you don't breathe vomit later, you sweat and your heart rate increases. While all that is going on your small intestine starts to work in reverse and sweeps your digestive tract contents into your stomach, then your abdominal muscles contract forcing everything into your esophagus and then finally out your mouth. There are usually a bunch of sphincters (like one way valves) that prevent this from occuring randomly, but during this process they all relax. The stomach and esophagus themselves don't do much other than relax and provide an open pathway for exit. Bunny thinks this whole process is really cool, particularly the saliva protection thing, but overall it's still also really gross.




http://www.dizziness-and-balance.com/treatment/drug/emesis.html

There are two phases - the "retching" phase - where your abdominal muscles contract with the diaphragm and breathing muscles all together. Next is the "expulsive" phase - which is exactly as it sounds. Pressure has built up in the stomach thanks to the diaphragm and abdominal muscles. That pressure gets released when the esophagus releases what is usually a one-way valve and whoosh - eggs and toast in the parking lot. The only good part is that pressure release and some associated endorphins make you temporarily feel better.


As I have decided not to put in any pictures of people vomiting, here is a picture of Beans and Bunny enjoying a post-virus treat that did not end up in reverse. I am now living in a state of fear as it's only a matter of time...I know it's coming for me.






Monday 4 November 2013

Mummy's Tummy (Crohn's Disease Awareness Month)

This question has come up from both Beans and Bunny a lot because it is a part of our daily life, as chronic diseases tend to be, and while I answer as best I can, it is one of the few things there isn't a good answer for.  But it also comes up from a lot of other people too. Why doesn't my tummy work right? (OK, maybe the grown-ups don't say "tummy")

November is Crohn's and Colitis Awareness Month, so I thought it was a good time to make people aware - I have Crohn's Disease. I was diagnosed 13 years ago and I do my very best to lead a "normal" life with it. Day to day life with Crohn's doesn't get talked about a lot because the symptoms themselves are a bit awkward to talk about - pain, nausea, vomiting, diarrhea, blood, mucus - not to mention the scramble for bathrooms. There's no good way to put that stuff in a casual water-cooler conversation. So, in honour of the month here's a bit about what it is, what it does and why my tummy doesn't work quite right. 



Let's start from the very beginning, a very good place to start. When we sing we begin with Do Re Mi. When we talk Crohn's we begin with the digestive system (Yeah ok, it's hard to rhyme "digestive system", my apologies to Julie Andrews). Digestive systems are pretty important, and also pretty long. There are a bunch of sections that all do a specific job:



from: http://www.ccfc.ca 


Mouth
It eats stuff. Like, say, chocolate. Nom nom nom.

Esophagus
The tube that connects your mouth to your stomach. Yup, pretty much just a tube that contracts.

Stomach
The food gets together with stomach acid and enzymes and breaks down into smaller pieces. Bet it's higher up in your body than you thought it was! The stomach actually does very little absorption of nutrients.

Small Bowel (Small Intestine)
It has three parts and digests the food and absorbs the nutrients. This is pretty much the most important bit there is because without it you can't get the nutrition out of food. 
    - Duodenum (about 8 cm in length) 
    - Jejunum (can be around 3 metres long)
    - Ileum (can also be approximately 3 metres in length)

Large Bowel (Large Intestine/Colon)
It's called "large" because of it's diameter, not length and is usually about 1.5 metres long. It includes the rectum and anus, which we have probably all heard of (and giggled about). It's job is to get the water and salt out of stuff and then store the waste until it is time to get rid of it.

So, in your average person these all work together and process your food efficiently and everything moves through according to schedule (except maybe for that sketchy taco...). But in those of us with Crohn's disease, the body's immune system attacks the gastrointestinal tract resulting in a chronic inflammatory disorder. This is the part that is tricky answering - WHY? I don't know. No one knows. There isn't an answer yet - research shows interactions between environmental, immunological and bacterial factors in genetically susceptible individuals (which is the science equivalent of "we're not quite sure yet"). 

The inflammation can occur in any part of the digestive system and in all layers of the tissues. The intestines become inflamed and ulcerous, and leaves behind scar tissue, which causes narrowing of the intestines, blockages and all kinds of other super fun things. As well, because the immune system is involved it is a whole body experience - arthritis and other random inflammation is par for the course. 

This is an awesome video that explains it better than I ever could:



And this comic is quite possibly one of the best explanations of living with Crohn's I've ever read, particularly the part about pretending to listen while in pain and finding random bathrooms. 




The part that is hardest to answer to the girls is "will you get better". Bluntly - no, I won't. But with meds, diet and a bit of luck I can live with it, so that's alright then. The most important part of living with Crohn's is a sense of humour, and online support groups are full of funny pictures and "bathroom humour" because to live with something like this requires laughing at it, otherwise it has too much power. Especially during colonoscopy prep. So, while I often make separate meals and carry toilet paper wherever I go - I go everywhere and do everything and I hope that that is the part they remember.

Thanks for listening. Feel free to ask questions!

If you'd like to learn more about Crohn's, this is a very good place to start: