The technology

The Insides System (The Insides Company) is a chyme reinfusion system designed to help people with high-output fistulas or stomas after bowel surgery. The system aims to infuse the effluent of the fistula or stoma into the distal gut.

The system works by chyme and intestinal fluid being pumped back into the distal intestines using an Insides Driver. The driver is a handheld battery‑powered device that connects magnetically to the Insides Pump found in the stoma bag. The driver powers the pump to refeed the content of the stoma bag back into the distal intestine. An Insides Tube is inserted into the distal intestine and connected to the Insides Pump as a tube to transport chyme. Five driver speed options are available to allow the person to control the rate of infusion manually, depending on tolerability and viscosity.


The company is not aware that there are other devices commercially available for reinfusing a fistula or stoma with chyme losses back into the distal gut. In clinical practice, chyme can be reinfused manually using a collection container, syringe, filter and tube. This is time‑consuming and labour intensive for staff because they have to manually collect the bowel contents and interfere with the stoma appliance (Kittscha 2016). The company claims that the device will allow an earlier return to oral feeding and could potentially reduce the need for parenteral nutrition and the length of stay in hospitals because of reduced risks of complications such as dehydration, malnutrition and loss of the gut microbiome. One expert noted that there is no evidence of any effect of changes to the microbiome. The company also claims that it could reduce the risk of liver and kidney damage. One expert added that the system is also likely to reduce the use of intravenous supplementation. At present, there is very limited published evidence to support the company's claims.

Current care pathway

Some conditions, including bowel cancer, diverticular disease and inflammatory bowel disease may need surgery that involves creating a stoma or fistula. The stoma or fistula will be created after intestinal resection when restoring bowel continuity is not possible. The stoma or fistula could be placed temporarily or permanently. People would be observed for signs of high output after stoma formation. If output persists, parenteral nutrition or enteroclysis would be needed to compensate for a persons' nutritional and fluid losses for a period of time. Often these people are in a high dependency unit in hospital. Some people may be discharged with home parenteral nutrition or distal enteral tube feeding depending on their nutrition status and ability to continue treatment at home.

The European Society for Clinical Nutrition and Metabolism (ESPEN) guideline on clinical nutrition in the intensive care unit (2019) states that in specific situations with high-output stoma or fistula, chyme reinfusion should be evaluated and performed if adequate.

Population, setting and intended user

The Insides System is intended for people with acute severe intestinal failure (type 2) after bowel surgery and people with persistent high-output double enterostomy and enteroatmospheric fistula whose small bowel is separated into 2 segments through a stoma or open wound. The technology is likely to be used by healthcare professionals such as nurses in specialist centres for treating intestinal failure.


Technology costs

The Insides System is a treatment consisting of loaned equipment and consumables, which need monthly refills. For people with type 2 intestinal failure with an enterostomy or people with type 2 intestinal failure with an enteroatmospheric fistula, the first month costs £2,400 (excluding VAT) and the subsequent months cost £1,900 (excluding VAT).

There are no maintenance costs and the patient is sent all the necessary equipment monthly to do chyme reinfusion. All maintenance costs are covered in this including any replacements. Clinicians may withdraw patients from using The Insides System at any time during treatment.

Costs of standard care

The intravenous delivery of nutrients and water (parenteral nutrition) is standard care for intestinal failure. When a person's condition has stabilised, home parenteral nutrition and ongoing maintenance care could be done at home with support from community healthcare teams.

One expert noted that people with intestinal failure can also self-administer distal enteral tube feeding or fistuloclysis (Teubner et al. 2004).

The company claimed that the average cost of home parenteral nutrition is between £4,447 and £5,212 per month per person. This includes additional medicines, nursing, products for home parenteral nutrition fluid bags, deliveries and ancillaries. One expert estimated that the current cost of home parenteral nutrition is about £75,000 per year (on average £6,250 per month). There will be costs associated if parenteral nutrition is delivered in hospital.

Resource consequences

The device has been used in 11 NHS trusts. Clinical experts said that The Insides System would be an additional option to standard care for intestinal failure management such as parenteral nutrition or would potentially replace distal enteral tube feeding.

The technology could be resource releasing if it leads to shorter hospital stays and improved outcomes for patients through improved nutrition management. However, its effect on treatment decisions and length of hospital stay has not been explored. The technology may free up nurses' time in hospital because patients can control the infusion themselves.

One expert said that training would be the same as for distal enteral feeding. The company said that training is needed to ensure patients are able to operate reinfusion themselves, including how to control the frequency and the speed of reinfusion.