Ileus

Paralytic Ileus is a condition where the intestines (small and large bowel) stop working.

How the bowel works.

  • The gut is a long tube from the stomach to the anus.
  • Food moves along that tube, being digested as it goes.
  • There are three main sections:
    • Small intestine – Mostly concerned with absorbing key nutrients directly;
    • Large intestine (colon) – Where microbes further digest the food, and water is reabsorbed;
    • Rectum – where stools are stored.

Peristalsis

  • Peristalsis is the mechanism that pushes food along.
  • Peristalsis consists of waves of muscle contractions around the bowel.
  • Peristalsis works like giant hand, squeezing the tube and stroking its contents towards the anus.
  • Peristalsis is largely Autonomic – this means that we don’t consciously need to tell which bit of gut to squeeze and move every time we digest a meal. It happens automatically.

Autonomic

There are sensors in the gut lining that are analysing the contents of the gut and acting accordingly – releasing enzymes, moving the food, or allowing it to stay put.

The Vagus Nerve sends signals to and from the autonomous systems in the brain and the gut.

Controlling the gut

  • We do develop a level of control of the last section of the gut, the descending and sigmoid colon, rectum and anus.
  • Conscious control allows us to hold in stools until an appropriate time when we can visit a toilet.
  • We can make ourselves defaecate if there are any stools in the rectum and last section of the gut.
  • Whilst we do not consciously control the rest of the gut, it is sensitive to our activity and mental condition eg, stress, or ‘fright or flight’.

Ileus

Ileus is a temporary stagnation of the gut. Sometimes called Paralytic Ileus.

  • Peristalsis stops
  • Loss of appetite
  • Food backs up into the stomach, or even the eosophagus
  • Bloated feeling
  • Unable to pass stools

Causes

  • Abdominal surgery
  • Infection inside the gut
  • Infection in the abdomen
  • Certain medications
  • Chemical or nutrient imbalances (especially potassiuim)
  • Pain
  • Kidney or lung disease

nb: A blocked bowel is a different condition.

Ileus and bowel cancer.

Ileus is not uncommon amongst people being treated for bowel cancer.

There are two main causes:

  • Abdominal surgery
  • Medication

Bowel cancer surgery is disruptive. Removing a tumour can have a significant impact on the rest of the gut and may cause ileus in different ways:

  • A typical resection removes a whole section of gut, not just the tumour;
  • A section of mesentery will be removed (this holds the gut in place and supplies blood, lymph and nerves);
  • The remaining sections of large intestine will be re-routed and lie in a different position in the abdomen;
  • The small intestine will be disturbed and repostioned;
  • Inflammation;
  • Post-operative infection
  • Anaesthetic and antibiotics can cause ileus.

Other treatments can also have an effect.

  • Chemotherapy
  • Steroids
  • Gut microbiome imbalances as a result of bowel prep or medication

Post-operative ileus

Following surgery, patients are kept in the ward until ready to go home. They are monitored for ileus and infection. Ileus is assumed to be absent if:

  • The patient passes stools.
  • A passage of wind (fart).

If it appears that ileus is a problem they may decide to feed the patient using a nasogastric tube whilst they wait for it to restart.

Getting the gut going again

The normal procedure is to wait and allow the gut to recover and settle itself. This may take 3 or 4 days.

There are things you can do to help it along.

As mentioned above, the gut is connected to the brain, and whilst we do not have free control over the way it works, the brain is aware of our behaviour and recognises patterns. It will trigger peristalsis and release of enzymes in response to aspects of your behaviour.

Here are some triggers that may help to stimulate the gut to start peristalsis again:

  • Learned behaviour – Going to the bathroom and sitting on the toilet can trigger peristalsis. This is what your mother was doing when you were potty trained;
  • Eating – For some people eating a meal triggers the emptying of the stomach in readiness for the incoming food;
  • Chewing – The act of chewing a food can trigger the digestion process as described above;
  • Favourite food – Just the thought or smell of a favourite food will quite literally get the juices flowing;
  • Routine behaviour – Some people are VERY regular in their bowel habit, eg, they go to the toilet at exactly the same time every day. Returning to this routine can be effective.
  • Coffee – Sometimes known as the ‘coffee pseudo-enema’, many people find that a strong cup of morning coffee will trigger a bowel movement. This may be due to some component of coffee, or the learned behaviour of a morning routine.
  • Activity – Moving around. Especially after a period of being bed-ridden;
  • Upright position – the effect of gravity can get things moving.

Complications

Sometimes the gut just won’t start again on its own.

  • Supplements – The well-known laxative Senna is a proven bowel stimulant;
  • Medications – There are a few medications that have the effect of triggering the emptying of the stomach and motivating peristalsis to move food through the gut, eg Domperidone;
  • Electrical stimulation – Giving the gut nerves an electrical stimulus – a bit like a defibrillator for the vagus nerve;
  • Surgery – Very rarely surgery is necessary to identify potential causes.

Occasionally we get a post from a member who has been sent home after surgery, but before the gut has restarted. The person maybe unaware that they have ileus. This can cause distress and usually lead to an emergency readmittance, IV nutrients and medical interventions to restart the gut.