More than 21 000 people per year in the UK have a stoma formed (Elliston et al, 2019), often due to conditions such as:
- Inflammatory bowel disease (IBD)-Crohn's disease or ulcerative colitis
- Bowel cancer
- Diverticulitis
- Bowel obstruction
- Ischaemic bowel
- Abdominal trauma.
A stoma is an opening that connects part of the bowel to the outside of the body, so waste products can be excreted into an external bag attached to the skin. The bowel consists of the large and small intestine. The large intestine (otherwise known as the colon) is made up of the caecum, ascending colon, transverse colon, descending colon, sigmoid colon and rectum. Its main functions include: the absorption of water, electrolytes and short-chain fatty acids and moving colonic contents towards the rectum for defaecation. The small intestine consists of the duodenum, jejunum and ileum. The average length of the small intestine is 3–5m, with an even larger surface area due to its surface folds, villi and microvilli. Its main functions are to digest food and absorb fluid, electrolytes and nutrients (Lomer, 2014; Collins et al, 2017).
The surgery involved to form a stoma will usually be to remove the diseased part of the bowel or to provide a period of rest for a section of the bowel (for example, to recover from inflammation). Therefore, stoma formation may be permanent or temporary.
Two types of stoma are commonly seen in district nursing: a colostomy, where the large intestine is connected to the skin opening, and an ileostomy, where the ileum, the last part of the small intestine, is connected to the skin opening. Table 1 outlines the different colostomy and ileostomy that may be formed. Table 2 demonstrates the surgeries that may be performed to form these stomas.
Table 1. The different colostomy and ileostomy that can be formed
| Types | Procedure |
|---|---|
| Loop colostomy | The colon is sutured to the abdomen and there are two openings: one for intestinal waste and one for mucus produced by the gastrointestinal tract |
| End colostomy (also known as a Hartmann's procedure) | The sigmoid colon and upper rectum are removed, an end colostomy is formed |
| Double−barrel colostomy | Both ends of the colon are brought out onto the abdomen |
| Temporary or loop ileostomy | A loop of the small intestine is brought to the skin, and the colon and rectum remain in situ. This is usually reversed 8–10 weeks later. |
| End ileostomy | The colon and rectum are removed, and the end of the small intestine is brought through the skin |
| Continent ileostomy | An internal pouch is created, and the stoma is connected to a valve implanted in the skin, which can be emptied using a catheter |
Table 2. Surgeries that may be performed to form colostomies and ileostomies
| Type | Procedure |
|---|---|
| Right hemi-colectomy | Right half of the colon is removed |
| Left hemi-colectomy | Left half of the colon is removed |
| Abdomino−perineal resection | Rectum and anus removed; colostomy formed |
| Anterior resection | Removal of cancer in the rectum |
| Sigmoid colectomy | Sigmoid colon removed; two ends joined together. |
| Hartmann's procedure | Sigmoid colon and upper rectum removed; end colostomy formed |
| Total colectomy | Entire colon removed, permanent ileostomy or small bowel will be joined to rectum |
| Pan proctocolectomy | Colon, rectum and anus removed; permanent ileostomy formed |
Short bowel syndrome (SBS) occurs when a patient has less than 200 cm of their small intestine (Cuerda et al, 2021), which affects the body's ability to maintain nutrients, fluid and electrolytes when on a normal diet (O'Keefe et al, 2006).
This article will look at dietary measures to help support patients with stomas, particularly those at risk of nutrient deficiencies due to high-output ileostomies or SBS.
Discussion
Fluids
Dehydration is common in patients with ileostomies, particularly those who have had large amounts of their ileum removed, and this can result in a readmission to hospital with dehydration or acute kidney injury (AKI) (Bakewell, 2017).
Postoperatively, the most common losses seen in ileostomy patients are fluids and sodium. Within the first 6–8 weeks, patients may lose 1200–2000 ml fluid and 120–200 mmol sodium/day. However, after approximately 8 weeks, the ileum usually adapts to absorb and fluid losses tend to reduce (Lomer, 2014).
Contrary to normal physiological function, patients with high-output ileostomies are discouraged from drinking additional fluids to improve hydration. This is due to the hypotonic nature of fluids such as water, tea and cordials, meaning patients can lose more fluid from their stomas than they consume. Patients with high-output stomas, producing >1500 ml/day (Arenas et al, 2015), are advised to limit hypotonic fluids and take an additional 1000 ml from an oral rehydration solution (ORS) to help replace electrolytes. This is detailed in the European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines, which recommends an ORS and fluid restriction for those who have borderline dehydration or sodium depletion (Cuerda et al, 2021).
Including an oral rehydration solution containing 90 mmol/L sodium, 20 g glucose, 3.5 g sodium chloride and 2.5 g of sodium bicarbonate is often advised (O'Keefe et al, 2006); however, for those with SBS, maximum sodium absorption occurs with a mixture of 120 mmol/l sodium chloride and 30 mmol/L of glucose (Cuerda et al, 2021). The addition of salt to meals may also help with sodium levels (Cuerda et al, 2021).
Examples of rehydration solutions include St Mark's solution or over the counter products such as Dioralyte™. However, Dioralyte should be made up to double the strength (10 sachets in 1L) to ensure it contains adequate sodium levels.
St. Mark's Solution can be made at home with the following ingredients:
- One level 5 ml teaspoon salt
- Six level 5 ml teaspoons of glucose powder
- One heaped 2.5 ml spoon of sodium bicarbonate
- Mixed in 1L water (St, Mark's Hospital, 2014).
Fluids are discouraged from being taken with meals, ideally avoided 30 minutes before and after eating, to reduce gastric fluid production which can increase fluid losses (St. Mark's Hospital, 2014). Types of fluids should also be considered, as fizzy drinks can cause excess gas in stoma bags and, therefore, patients may choose to limit or avoid these.
Fibre
It is common for patients to be advised to follow a low-residue (low-fibre) diet in the first 6–8 weeks following both colostomy and ileostomy formation. However, after this time period, there are few strong clinical trials to support any particular diet (Mitchell et al, 2021).
Dietary fibre can be described as a form of complex carbohydrate, found in plant products such as vegetables, wholegrains, pulses, nuts and seeds. Unlike other forms of carbohydrates, fibre is not digested nor absorbed in the small intestine but passes through to the large intestine to be broken down and add bulk to stools. It helps to regulate our bowel movements and diets that are high in fibre have been linked to reducing the risk of diabetes, bowel cancer and helping to lower cholesterol (British Nutrition Foundation, 2018).
Following this 6–8-week period, patients should be encouraged to aim to return to a healthy, balanced diet with plenty of fruit and vegetables if a normal stoma output volume/consistency has been achieved (Lomer, 2014). Fibre tolerance will be individual and some patients may easily return to a diet high in fibre, whereas others may have to reintroduce these foods at a slower rate, or limit some altogether. For patients with ileostomies, there are certain foods that should be taken with caution, as they risk causing a blockage of the stoma (Table 3). Further dietary advice focuses on adjusting foods depending on stoma function, for example, avoiding foods which cause more gas or odour (Table 3).
Table 3. Foods that may affect ileostomies
| Stoma obstructives | Gas producing |
|---|---|
| Apple peel | Beans/pulses |
| Sweetcorn | Cabbage |
| Beansprouts | Broccoli |
| Dried fruit | Cauliflower |
| Nuts | Alcohol |
| Mushrooms | Onions |
The addition of soluble fibre to enhance absorption in the intestine for ileostomy or SBS patients is not recommended (Cuerda et al, 2021). For patients who have had surgery for cancer, constipation may occur due to medication use, reduced activity or poor diet and fluid intake. Ensuring that patients with constipation have adequate dietary fibre and fluids can help to improve gastrointestinal (GI) function (Doughty, 2005).
Dated research looking at patients with ileostomies who have a persistent high-output (>1.5 L per day) suggest that a low-fibre diet may need to be followed long-term, as this has been shown to improve output consistency and volume (Silvester et al, 1995). Despite its use in clinical practice, there is little current evidence to support this and clinicians/dietitians usually base this on anecdotal evidence (Mitchell et al, 2021). The following is advised in the ESPEN guidelines(Cuerda et al, 2021) to help control output and support nutritional status:
- Chew all food thoroughly (40 chews per bite)
- Eat smaller meals more often, eating the most nutritious food first
- Limit fluids with meals
- Separate solids and liquids at meals-eat solids first as they slow digestion.
Micronutrients
De Oliveria et al (2018) noted that many patients, particularly those with ileostomies, restrict their dietary intake, putting them at risk of micronutrient deficiencies.
A patient's ability to absorb nutrients will also depend on how much of their small bowel is remaining, and if their colon has been removed or not. Most nutrients are absorbed in the first 100-150 cm of the small intestine (except for bile acids and B12, which are absorbed in the terminal ileum). As a result, there is evidence that patients with SBS experience a higher prevalence of micronutrient deficiencies (Lomer, 2014). Patients with SBS may have a normal diet, use enteral or parenteral nutrition to supplement this or as their sole nutrition source. The length of bowel remaining and area of resection often dictates which nutritional support is required:
- A 100–200cm small intestine may be managed with oral diet and fluid management
- A <100 cm jejunum requires long-term parenteral fluid and electrolyte replacement
- A <75 cm requires long-term parenteral nutrition, fluid and electrolyte replacement
- A <50 cm jejunum plus colon requires long-term parenteral nutrition (TPN), fluid and electrolyte replacement (Nightingale and Woodward, 2006).
For patients with a preserved colon, a diet higher in complex carbohydrates and lower in fat (but including medium-chain triglycerides), may be of benefit. However, deficiencies in fat-soluble vitamins A, D, E and K and fatty acids should be monitored. For patients without a colon, the fat to carbohydrate ratio is deemed to have less importance. The removal of lactose is not advised unless a lactose intolerance has been confirmed (Cuerda et al, 2021).
Supplementation of micronutrients, often over the recommended dose, is required to manage deficiencies (American Gastroenterological Association, 2003) and clinical signs, symptoms and biochemical measures of trace element deficiency (or toxicity) should be regularly evaluated (Cuerda et al, 2021). Monitoring biochemistry is also important to assess hydration levels in patients with ileostomies.
Following a total colectomy, the absorption of other nutrients should be unaffected, as the absorptive capacity of the small intestine remains intact. An estimated 3–9% of patients have vitamin B12 deficiency, and some patients may find absorption of bile acids are also affected. This is thought to be due to reduced absorptive capacity due to ileal involvement, inadequate dietary intake or bacterial overgrowth. As the ileum contains B12 receptors and bile salt transporters, those patients who have had ileal resection often have B12 deficiency and fat malabsorption. Fat malabsorption may lead to steatorrhea (loose, oily and light-coloured stools/output) and deficiencies in fat-soluble vitamins A, D, E and K (Borwell, 2009; Matarese, 2013).
Pharmacological
In addition to dietary management, medications are often required for patients with ileostomies to help control ileostomy output by slowing transit time, resulting in improved nutrient absorption. The use of H2-receptor antagonists or proton pump inhibitors (PPIs) may be used to reduce faecal weight and sodium excretion. This is especially useful during the first 6 months after surgery for patients with a stoma output exceeding 2 L/day; however, they may also be prescribed for long-term management (Cuerda et al 2021; National Institute for Health and Care Excellence (NICE), 2022). Antimotility medications can be used to decrease intestine transit time, which can decrease stoma output and reduce nutritional losses (Mackowski et al, 2015). A common medication used for this is loperamide hydrochloride, which may be given in higher than recommended doses (>16 mg/day), and sometimes in conjunction with codeine phosphate (Mackowski et al, 2015; NICE, 2022). For patients with an intact colon but <100 cm of their jejunum remaining, Cholestyramine may be prescribed to bind to unabsorbed bile acids, which may contribute to symptoms of diarrhoea. In addition to this, supplements to replace vitamin/mineral deficiencies may be prescribed (NICE, 2022).
Soluble tablets, liquids, capsules or uncoated tablets are more suitable for stoma patients, as they dissolve at a faster rate. If patients are using tablet or coated forms, the stoma bag contents should be checked for any remnants. Medications containing sorbitol preparations should also be used with caution as they have laxative side effects (NICE, 2020).
Psychological impact
Stoma formation is a major surgery and involves a great deal of aftercare and skills needed to be learnt by the patient, therefore, the correct support and follow-up is vital. Stoma nurses play a crucial role in teaching skills, such as stoma care and changing stoma bags, and research has shown that the early promotion of stoma-management skills improves the psychological adjustment that is required following a stoma formation (O'Connor, 2005). Further studies also suggest that this should be continued upon hospital discharge, as the need to acquire all practical skills for stoma care within the short period of hospitalisation may lead to psychological distress and stressful preparation for discharge (Persson and Hellstrom, 2002; Readding, 2005; Fulham, 2008). Despite these suggestions, experiential literature has shown that this does not always occur due to staff shortages and increased workloads (Di Gesaro, 2012).
There have been several studies that have looked into the psychological effect that stoma surgery can have on a patient and conclude that it can often lead to a series of physical and psychological stresses, as well as maladjustment and poorer health outcomes (Broadbent et al, 2003; Di Gesaro, 2012). Patients with a stoma may also have higher levels of depression than those without (Von et al, 2007).
The type of surgery should be considered when offering psychological support, as several clinical studies have reported that patients who have emergency stoma surgery may have greater difficulties adjusting to the sudden body image change and functional loss, due to the patients having little time to anticipate or accept their future living with a stoma (Cotrim and Poteiria, 2008; Fulham, 2008). These findings emphasise the importance of nurse assessment of patients' mental health and the need to provide relevant psychosocial care for patients following stoma surgery.
Conclusion
Health professionals in the community-including both nurses and dietitians-can play a key role in supporting patients to achieve a balanced diet, avoiding nutritional deficiencies, achieving optimal stoma output consistency and preventing dehydration. Despite there being guidelines and published researched on stomas and dietary advice, it is thought that much of these recommendations come from expert opinion, rather than strong clinical evidence, which has been highlighted in two separate reviews by Mitchell et al (2020; 2021).
In a recent scoping review, Mitchell et al (2021) recognised that there is an abundance of literature on dietary management and ileostomy but suggests that stronger studies need to be concluded to support the evidence base (Mitchell et al, 2021). This presents similar findings to an earlier study by de Oliviara et al (2018), who found few papers that discuss both the nutritional status of patients with stomas or the effect diet may have.
Mitchell et al (2020) also found that there needs to be better collaboration between healthcare professionals providing high-quality dietary advice for patients with stomas, as inconsistencies across advice were given. ESPEN guidelines state that dietary management for patients with intestinal failure or SBS should be guided by a dietitian who is an expert in this field (Cuerda et al, 2021).
Anecdotally, it is clear that diet manipulation, fluid and electrolyte management is vital, particularly in patients with ileostomies and those with little remaining small intestine. However, a stronger evidence base should be built to support this patient group in the future.