Tessa Davis. Abdo Pain Week, Don't Forget the Bubbles, 2015. Available at:
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Education of the child and family of the physiology of constipation and mechanism of overflow soiling is important. Below are some tips, tricks, and generally things not to forget.
What other recommendations can I give?
You can mix the PEG 3350 with other fluids:
Use a foot stool:
If behavioural techniques fail, consider referral to a paediatric occupational therapist for further advice.
Where can I find a good information sheet?
Good information sheets:
Good websites to refer parents to:
Bracewell M, Bunce N. Movicol Paediatric Plain: A Treatment for Constipation in Children. Sussex Community NHS. 2009 July. https://gp.westernsussexhospitals.nhs.uk/wp-content/uploads/gpsiteweb/Leaflet11movicol-AssetID=354390&type=full&servicetype=Attachment.pdf
Sikirov BA. Primary Constipation: An underlying mechanism. Medical Hypotheses. 1989 February;28(2):71-73.
Lowery S, et al. Habit Training as Treatment of Encopresis secondary to Chronic Constipation. Journal of Pediatric Gastroenterology & Nutrition. 1985 June;4(3):397-401.
It may seem mundane, but successfully managing constipation can make a massive difference to the lives of families. Although it’s all about faeces; it can lead on to other issues including pain and social embarrassment. Time spent managing this can have a knock on effect on the whole family, as well as the patient.
Normal bowel movements vary with age:
|Age||Stools per day||Mouth to rectum time (hrs)|
|<3 months||2 to 3||8.5|
What happens to poo?
As stool goes round the colon and out to the rectum, water is reabsorbed. So by the end, it will be smaller and harder than it was when it was at the appendix (which is why colostomy bags initially have a watery output). Hard poo is sore to pass so children often don’t want to pass it at all. Therefore it collects, and stays in the bowel longer getting more and more impacted. If stools takes a longer time to pass through the colon, it will become harder and drier. So the treatment is based around adding water to it, and getting things moving.
There are 3 periods when children are prone to developing constipation: the introduction of solids; toilet training; and starting school. These all have the potential for defecation to be an unpleasant experience, prompting the child to consciously or subconsciously avoid repeating it.
This painful defecation can then leading to avoidance of defecation which results in stool accumulation in the rectum. The stool becomes harder and therefore more painful to pass. Chronic rectal distension leads to relaxation of the internal anal sphincter and semi-solid stool leaks or soiling. Finally, the rectum is unable to generate enough pressure to pass stool.
What causes constipation?
Causes can be split into functional and organic.
This is an umbrella term for difficult, infrequent, or incomplete defecation with no structural or biochemical cause. It accounts for 95% of constipation.
This is constipation associated with an organic condition which accounts for 5% of constipation. Organic causes are anatomic malformations; metabolic; gastrointestinal; neurological; connective tissue disorders; drugs; miscellaneous.
If functional accounts for 95% then we should know more about it – what’s the mechanism?
There are several mechanism for this:
What is reservoir constipation?
Reservoir constipation is where the stools collect in the bowel and start to get larger and larger.
This is commonly seen in 5-10 year old boys.
The history is often of passing a large diameter stool every 1-2 weeks. Often because it’s painful to pass these, children can be scared to pass stools and hold them in. This causes the rectum to stretch due to pressure on the rectum. Then the nerves in the wall of the rectum stretch causing a problem with the internal sphincter. A problem with the internal sphincter means that children may be able to hold onto their stools on the journey home (using their external sphincter) but then as soon as they relax at home they will get some soiling.
These children have a numb, toneless rectum which means that they then don’t realise when it’s time to pass stools.
Reservoir constipation can occur because children are too busy to poo, find the toilets too dirty to use (or not private enough), or are scared of pain.
There are other causes of constipation too. For example, there are some psychological causes of encopresis and also some neurological causes. Any clinical examination should be careful to look for neurological signs: check for spina bifida occulta, look for any sinuses or fissures; look for a patulous anus.