POEM (per oral endoscopic myotomy)

Oesophageal POEM

Written Dr Cameron SCHAUER

 This is an information sheet about POEM: Peroral Endoscopy Myotomy.

You will have a diagnosis of achalasia or swallowing disorder or gastroparesis where this procedure has been recommended as a potential treatment option. A separate information sheet on achalasia can be provided to describe this condition, tests and all treatment options. 

What?

O-POEM (oesophageal per-oral endoscopic myotomy) was developed in 2008 as a minimally invasive method for the treatment of achalasia. Click for more information on achalasia

 5 years later, G-POEM (gastric per-oral endoscopic myotomy) was invented to treat gastroparesis. 

O-POEM: An endoscopic technique used for cutting of the oesophageal muscles and lower oesophageal sphincter (LOS) to relax this and allow food to flow more easily out of the oesophagus.

2 minute video:

G-POEM: A similar technique used to cut the pyloric muscle (the valve between your stomach and small bowel) to relax this to allow food to flow more easily out of the stomach. 

2 minute video:

How?

An electrical scalpel, 2mm long is passed through the gastroscope (a thin, 9mm, 1 metre long diameter tube) to make an incision (1.5cm long) in the lining of the tract. I create a tunnel within the wall of the oesophagus or stomach (between the inner lining of the tract and the outer muscle layer of the tract). The gastroscope is advanced into that tunnel, and the muscle of the oesophagus (O-POEM) or pylorus (G-POEM) cut full thickness to relieve the pressure. The entrance to the tunnel is then closed with temporary metal clips, so no leakage of contents can occur.

The procedure generally takes 60-90 minutes, completed under full general anaesthetic (you will be completely asleep, with a machine assisting your breathing).  

Why?

Cutting the overly tight and rigid oesophageal (O-POEM) or pyloric stomach (G-POEM) muscles may allow food to propel down more easily to relieve symptoms.

 Risks:

 POEM is minimally invasive and safe and serious complications are rare.

• Bleeding: bleeding can usually be stopped with coagulation during the case. Rarely, late bleeding can happen for up to 2 weeks after the procedure and would require a prolonged hospital admission and treatment including the requirement for blood transfusion. This may require surgery or interventional radiology to stop bleeding.
• Perforation: this is when a hole is made in the oesophagus or stomach wall and occurs <1% of the time. This may require a prolonged hospital stay or even surgery.
• Infection: 5 days of antibiotic are provided to reduce this risk. This may include lung infections from aspiration (food coming back down the wrong tube) and mediastinitis (<1%) in which fever and pain occur and intravenous antibiotics are required.
• Leak at the entry point due to dislodged clips. This is the most serious and feared complication. This is very rare and may require surgical assistance and a prolonged period of artificial feeding to allow things to heal.
• Reflux in O-POEM may occur 10-30% of the time, with the vast majority treated with omeprazole (ant-acid medication). If persistent reflux occurs despite this, anti-reflux surgery can be performed.

If you have a fever, vomit more than ½ cup of fresh red blood or have persistent tarry black stools I should be notified.

Outcomes:

What are the chances this fixes my swallowing problem?

 Success is variably defined in the research literature.

 It is important to understand that whatever intervention modality (balloon, surgery, POEM) you choose, the swallow you have may never be completely normal.

This is because the muscles in the oesophagus are not working properly. This means that food is not being propelled down in a synchronous, co-ordinated fashion, as would occur in a normal oesophagus. The interventions we perform are designed to disrupt the overly-tight muscles at the very bottom (the junction of the oesophagus and the stomach). We cannot intervene to “restart” the oesophageal peristalsis higher up. We don’t know why this condition has developed in the first place, whereby the nerves that supply these muscles have stopped working. Therefore how exactly things may be after the operation can also be difficult to predict.

However, with that said, in a study of POEM from New Zealand, success (resolution of swallowing issues) at 6 months was 93%, and 88% at 12 months. This is similar to literature in other countries.  

What may happen in the future?

As discussed above, it is difficult to know. For some patients, it may be the only intervention that is needed. In others, there may be recurrence of swallowing difficulty and repeated interventions may be required.

Sometimes, the junction can start to tighten again. In others, the upstream oesophagus completely stops working (“end-stage achalasia”) and further interventions are unlikely to help. Sometimes in these cases, an oesophagectomy (total removal of the non-functioning oesophagus) will be required.

In one study looking at 10 years of follow-up data, 27% of patients required some additional re-intervention due to recurrent symptoms.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7895648/

In another study, >90% had ongoing clinical success at 5 years of follow-up.

https://www.sciencedirect.com/science/article/abs/pii/S0016510721013481

Long term treatment success may be greater in patients who have not had other interventions prior (i.e. balloon dilation, Heller’s myotomy etc). In addition, it may be more successful if you have had the disease duration for a shorter period of time (i.e. so the remaining oesophagus is not so abnormal (i.e. very dilated).

Preparation for the procedure:

1. Take your usual medications. You will receive instructions regarding blood thinners separately which will need to be stopped.
2. 2 days before: have liquid diet only: clear soups, jelly, ice cream, yoghurt. Drink one litre of coca-cola (diet, zero or regular). This will help to dissolve foods sitting in the oesophagus or stomach (the oesophagus has to be completely clear to perform the procedure).
3. 1 day before: liquids only, and another one litre of coca-cola.

There may be special scenarios in which the instructions will be modified for you and my team will make this clear to you. Most often this will be that an additional day is required to the above regimen on a liquid-only diet due to a particularly severe condition).

 After the procedure:

It is common to have some chest or abdominal discomfort. You will be given pain relief. You will be admitted overnight to hospital for monitoring and pain relief as needed. You can have ice chips to keep the mouth moist, but we want you to have 24 hours with nothing to eat or drink to allow the operation site to heal. After this period, you will be given some water as a trial to drink. If this goes down without an issue, you can head home.

Some patients may feel completely fine and wish to go home after the procedure. This is OK, as long as you have someone at home to keep an eye on you.

On discharge you will be given a prescription for:

• Omeprazole 40mg twice daily for 3 months (to reduce acid and allow wounds to heal and prevent reflux)
• 5 days of antibiotics to prevent infection
• Anti-nausea medication as needed

You can resume normal activities as you wish 1 day after the procedure. It is best not to over-exert yourself but no harm will be done with things like heavy lifting, for example.

What happens afterwards:

Things can take some time to settle and improve. I will aim to see you in my clinic at 6 weeks post procedure to assess symptoms.

Preparing for your recovery

It is important to begin planning how you will manage after you are discharged home.

Eating and drinking

You will need to plan your meals for the first few days after your procedure, and shop accordingly.

To reduce discomfort and allow your stomach to heal, it is recommended you follow a modified diet.

• Initially you should drink only liquids, then advanced to a pureed then soft diet.
• As the swelling heals, you will be able to resume a normal diet.
• Eat slowly and chew food thoroughly
• Eat small, frequent meals to avoid putting to much pressure on your stomach.
• Eat sitting upright, try not to lie flat after meals

Examples of liquid and soft diets are below. This is a guide only. Some patients need longer at each step and this is absolutely OK.

Day 1 – A liquid diet only

Water only. 

Day 2-3 – Any liquids:

Liquid drinks such as water, juice and milk will be easiest to drink the first day, and you may find it useful to sip small amounts often.

Nutritious drinks are drinks which have more energy and/or protein than water, tea or coffee.

Milky drinks are a good source of energy and protein.

Powdered options:

• Milo, Horlicks, Bournvita, Ovaltine, Nesquik, drinking chocolate – made with milk
• Complan, Vitaplan, Sustagen, Ensure, Fortisip.

Ready to drink options:

• Standard full fat (dark blue top) or high protein (yellow or orange top) milk, soy milk or flavoured milk.
• Drinking yoghurts, fruit smoothies, Up & Go, Calci-trim Liquid Breakfast, Primo Extremo.

 Juice based drinks

These are a good source of energy and a suitable alternative for those who do not like milky drinks. Examples include:

• Fruit juices or drinks eg. Just Juice, Ribena, cordial, Raro/ Vitafresh
• Sports drinks eg. Mizone, Powerade.

What if I am “lactose free” or “dairy free”?

It is still important to consider nutritious drinks as a supplement to your diet. If you are lactose free consider using lactose free milk in place of standard milk. If you are dairy free it is best to choose soy milk or goats’ milk as these contain more protein and energy than other milks such as almond, rice or oat.

 Oral care

It is important to maintain good oral hygiene practices for your oral health.  This includes brushing teeth regularly and drinking water after a sugar sweetened drink.

Days 4-5 – A liquid & puree diet

Pureed meals can be made by cooking foods until soft and tender, and then blending them through a kitchen whiz or blender.
Adding sauces and gravies helps to moisten foods and makes it easier to swallow

Days 6-7 – A soft diet only

Food should be naturally soft or may be cooked to make sure it is soft enough. These foods can be chewed easily