Summary of Best Evidence for the Dietary Management in Patients with High-Output Ileostomy

Introduction

Temporary ileostomy is a versatile procedure used in both emergency and elective surgical settings. It is vital for managing acute conditions such as perforated or obstructed colorectal cancer (CRC), and it is also commonly employed in elective rectal cancer surgeries like anterior resection to protect the anastomosis. In China, it is estimated that approximately 100,000 new ileostomies are created each year, contributing to a cumulative total of around 1 million cases to date.¹ In the management of CRC or inflammatory bowel disease (IBD), ileostomy may be necessary, involving the exteriorization of an ileal segment through the skin to eliminate feces either temporarily or permanently.²

The creation of a stoma disrupts the natural passage of chyme and effluent through the gastrointestinal tract, thereby impacting the absorptive process. Ileostomy, located at the terminal ileum, significantly impairs absorptive capacity in the postoperative phase, reducing the absorptive surface area of the intestine, leading to the excretion of undigested food and substantial loss of digestive fluids. Furthermore, increased fluid and electrolyte loss through the stoma raises the risk of malnutrition, with an incidence rate ranging from 40% to 79.09%.^3–5 High-output stoma (HOS) is a significant postoperative complication among these patients, leading to early readmission rates between 12.9% and 43%.^6,7 A high-output stoma is typically defined as a stoma output exceeding 2 liters per day, though some clinicians use a threshold of 1.5 liters over 24 hours.⁸ HOS can cause severe complications such as dehydration, electrolyte imbalances, and acute renal failure.⁹ Infusion-based therapies are crucial for managing water and electrolyte imbalances. However, individuals with ileostomies are often advised to adjust their diet to manage their condition effectively.¹⁰ Evidence suggests that dietary modifications can significantly reduce stoma output in patients with HOS.^10–12 The ostomy diet plays a vital role in maintaining normal stool characteristics post-surgery, as stool volume, frequency, and consistency are greatly influenced by dietary intake¹³. The primary goal of dietary management is to reduce stool volume and improve its consistency.

However, in China, there is currently a lack of systematic evidence-based recommendations for the dietary management specifically tailored to patients with high-output ileostomies. This study employs evidence-based nursing methodology to systematically search, evaluate, extract, and synthesize the best available evidence for the dietary management in patients with high-output ileostomy. The primary aim is to provide healthcare professionals with a comprehensive reference for developing the effective dietary management protocols for this patient population.

Materials and Methods

Problem Establishment

The research question was formulated using the PIPOST model developed by the Shanghai Fudan University Evidence-based Nursing Center.¹⁴ The model identifies patients with preventive ileostomies as the target population, with interventions focusing on evaluation, prevention, screening, and management of nutrition. The application of evidence involves healthcare professionals and nutritionists, with outcomes measured by the incidence rate of malnutrition. The evidence is applied in gastrointestinal surgery wards and stoma clinics, and the types of evidence include best practices, evidence summaries, guidelines, systematic evaluations, expert consensuses, and original research.

Retrieval Strategy

Following the “6S evidence model“ evidence pyramid,¹⁵ a comprehensive literature search was conducted across various databases, including UpToDate, BMJ Best Practice, GIN, NICE, SIGN, NGC, MedLive, clinical guide networks, RNAO, Cochrane Library, JBI, PubMed, Web of Science, CINAHL, CNKI, and Wanfang Database. Additional searches were performed on websites of relevant associations such as WCET, UOAA, CSPEN, ESPEN, and ASPEN. The search used keywords like “Ileostomy/Stoma”, “diet*/Food/nutrition/dietary management/nutrition management”, combining free-text terms and MeSH, tailored to each database. The search covered all available literature from the inception of each database to January 2024. An example of the PubMed search strategy is provided in Table 1.

Table 1 Literature Search Strategy of PubMed

Literature Inclusion and Exclusion Criteria

Inclusion criteria focused on literature about adult patients (≥18 years) undergoing ileostomy surgery, addressing dietary or nutritional management. Eligible research types included clinical decisions, guidelines, evidence summaries, expert consensuses, systematic reviews, and original research closely related to the topic, with studies in Chinese or English. Exclusion criteria included guideline interpretations or protocols, duplicate publications, studies failing quality assessment, those with incomplete information, or where the full text was unavailable.

Quality Assessment and Evidence Grading

Quality assessment was conducted using standardized tools appropriate for each literature type. Guidelines were evaluated using the updated 2017 AGREE II tool.¹⁶, classifying them into three grades based on their standardized scores across six domains: Grade A for guidelines with all domains scoring ≥60%, Grade B for those with ≥3 domains scoring ≥30% but some <60%, and Grade C for those with ≥3 domains scoring <30%. Systematic reviews were assessed using the JBI Critical Appraisal Checklist for Systematic Reviews (2016 version),¹⁷ and expert consensuses and opinions were evaluated using the JBI Critical Appraisal Checklist for Text and Opinion Papers (2016 version).¹⁷ UpToDate from authoritative databases was directly considered high-quality evidence. Two researchers independently evaluated all included literature guidelines, with disagreements resolved through consultation with a third arbitrator experienced in evidence-based methodology and clinical practice. When conflicting evidence arose, priority was given to evidence-based, high-quality, and most recently published literature. The 2014 version of the JBI Levels of Evidence and Grades of Recommendation system was used to grade evidence and formulate recommendations. Evidence was classified into five levels based on the type of original research, with Level 1 representing the highest quality and Level 5 the lowest. An expert panel, comprising an evidence-based nursing expert, two stoma care nursing specialists, a nutritionist, and a gastrointestinal surgery medical expert, evaluated the evidence for effectiveness, feasibility, appropriateness, and clinical significance, determining recommendation strengths as either Grade A (strong) or Grade B (weak).

Results

Literature Search Results

The initial literature search yielded 1982 articles, which was reduced to 1865 after removing duplicates. After initial screening, 61 articles were selected for full-text review, and 18 articles were ultimately included: 2 clinical decisions,^18,19 5 guidelines,^20–24 3 expert consensuses,^25–27 6 expert opinions,^28–33 and 2 evidence summaries.^34,35 The literature screening process is illustrated in Figure 1, and the general characteristics of the included literature are presented in Table 2.

Table 2 Characteristic of Included Literature (n=18)

Figure 1 Flowchart of Literature Screening. Abbreviations: RNAO, Registered Nurses’ Association of Ontario; ASCN, Association of Stoma Care Nurses UK; WOCN, Wound, Ostomy and Continence Nurses Society; UOAA, United Ostomy Associations of America; ETN, Enterostomal Therapy Nurses Network Group of Ontario for Rapid Recovery Surgery; JBI, Joanna Briggs Institute; CNKI, China National Knowledge Infrastructure; VIP, China Science and Technology Journal Database.

Quality Evaluation of Included Literature

The quality of the included literature was assessed using standardized tools. Clinical decisions were directly incorporated as high-quality evidence from authoritative databases. Guidelines were evaluated using the AGREE II tool, and expert consensuses and opinions were assessed using the JBI Critical Appraisal Checklist for Text and Opinion Papers, both deemed relatively high quality. Evidence summaries were analyzed by tracing and evaluating the original literature, with specific assessment criteria applied. The detailed quality assessment results are summarized in Tables 3–5.

Table 3 Quality Evaluation of Included Guidelines (n=5)

Table 4 Quality Evaluation Results of Expert Consensuses (n=3)

Table 5 Quality Evaluation Results of Expert Opinion (n=6)

Evidence Synthesis

The research team analyzed and extracted 30 pieces of best evidence, focusing on five key aspects of dietary management for patients with preventive ileostomy: nutritional risk screening, monitoring and assessment, strategic dietary guidance, dietary behavior guidance, and health education and follow-up. These themes provide a comprehensive framework for managing dietary needs in this patient population (Table 6).

Table 6 Evidence Summary of the Dietary Management in Patients with High-Out Stoma

Discussion

Comprehensive Nutritional Risk Screening and Assessment

The ileostomy is pointed at the terminal ileum, and due to the reconstruction of the gastrointestinal tract, the physiological function of the ileocecal valve in regulating the emptying of the small intestine is lost.³⁶ This results in an increased propulsive rate of the small intestine, with food being rapidly expelled through the small intestine. The reduced contact time between nutrients and the intestinal mucosa leads to impaired nutrient absorption,³⁷ which can easily lead to progressive malnutrition in patients, necessitating comprehensive nutritional risk screening for all patients undergoing ileostomy surgery.^25,26,38,39 The Nutritional Risk Screening 2002 (NRS 2002) tool, with its high sensitivity and specificity, is recommended for nutritional risk screening in hospitalized patients.^25,26,39 An NRS 2002 score ≥3 indicates nutritional risk and necessitates further nutritional status assessment.⁴⁰ For a more comprehensive nutritional assessment, the Patient-Generated Subjective Global Assessment (PG-SGA) is widely recognized and recommended.²⁵

Regular implementation of nutritional risk screening and current nutritional status assessment serves multiple crucial purposes. It enables timely identification of individuals at risk of malnutrition, facilitating early intervention with individualized, targeted nutritional therapy plans. Furthermore, it allows for dynamic evaluation of nutritional intervention efficacy and refinement of nutritional plans. This approach contributes significantly to the effective implementation of nutritional management strategies and the improvement of clinical outcomes for patients.

Current guidelines do not specify precise screening frequency. Therefore, clinicians should tailor the frequency of nutritional risk screening and assessment to individual patient circumstances, ensuring continuous nutritional surveillance throughout the entire course of diagnosis and treatment.

Precise Monitoring and Assessment of Stoma Output

The normal output volume for an ileostomy ranges from 600 to 1200 mL/day, influenced by fluid intake and food digestion.²⁹ High-output stoma (HOS) is defined as an output exceeding 1500 mL/day for two consecutive days.⁶ Patients typically exhibit weight loss, dry mouth, thirst, reduced urine output, and decreased blood pressure.⁴¹ Regular monitoring of patients’ weight and blood pressure and dietary intake is crucial, and after discharge, the patient should be monitored once every three months. The creation of an ileostomy reduces the surface area of the absorbable intestinal segment, and a large amount of water is expelled without being reabsorbed by the colon, which can easily lead to dehydration and water-electrolyte disturbances in patients, and may induce acute and/or chronic kidney damage.⁴¹ Therefore, maintaining the patient’s fluid balance is extremely important. It is recommended to use a measuring cup to accurately record the patient’s urine volume and stoma effluent, and to observe the color and consistency of the effluent. Daily monitoring of dietary intake is also advised, along with keeping a food diary to closely track which foods do not cause discomfort, which foods are difficult to digest, and which foods produce odors.

Urinary electrolytes are typically easier to identify early electrolyte disturbances than serum tests, as normal physiological homeostatic mechanisms maintain serum electrolyte concentrations, and the urea/creatinine ratio only increases when dehydration is severe. So in the early postoperative period, it is recommended to monitor serum urea, electrolytes, creatinine, and random urine sodium concentration every 1–3 days. For hospitalized patients with stable conditions, weekly monitoring is sufficient. Post-discharge, these parameters should be assessed every 2–3 months.

Stool samples should be collected for Clostridioides difficile toxin testing in cases of high output, to rule out potential diseases outside of the stoma.⁶ Patients with ileostomies are at risk of vitamin B12 deficiency, as B12 is a large molecule vitamin primarily absorbed in the terminal ileum and colon. Its absorption and metabolism require intrinsic factor in the gut; when there is a deficiency or dysfunction of intrinsic factor, B12 from food cannot be absorbed. Consequently, Annual blood tests for vitamin B12 levels are recommended to prevent deficiency.³²

Optimizing Dietary Structure to Reduce Stoma Output

The restoration of intestinal function following ileostomy typically requires 4–6 weeks. In the immediate postoperative period, a low-residue, low-fiber diet is recommended to alleviate intestinal edema, promote better digestion, and facilitate intestinal function recovery.^21,28 Spicy and high-fat foods may induce diarrhea and/or reflux.²⁸ Therefore, a low-fiber, low-residue, low-fat, and mildly-seasoned diet is advised for 4–6 weeks post-surgery.

During the early postoperative phase, patients should avoid raw fruits and vegetables. For the first six weeks, cooked or canned fruits are preferred to reduce the risk of diarrhea. In the early postoperative period, the intestine is often in an inflammatory and edematous state, making large food particles difficult to digest and potentially increasing stoma output.^10,32 Consequently, high-fiber, viscous, or difficult-to-digest foods such as nuts, corn, celery, asparagus, popcorn, coconut, or mushrooms should be avoided for 6–8 weeks post-surgery. Dietary fiber can be gradually reintroduced as gastrointestinal function improves.

Reports indicate that approximately 20–40% of ileostomy patients experience dehydration postoperatively, which is one of the most common causes of early readmission (within 30 days post-surgery).^42–44 Patients with high-output stomas (HOS) may experience intense thirst when water and sodium are depleted. This can lead to increased consumption of hypotonic fluids such as water, tea, coffee, fruit juices, alcohol, or dilute saline solutions. This not only increases stoma output but also exacerbates sodium loss, further intensifying thirst.

For patients with stoma output exceeding 1.5–2.0 L/day, it is crucial to limit hypotonic fluid intake to 0.5–1.0 L/day to prevent further output increases.²⁹ Due to the coupled absorption of sodium and glucose in the intestine, patients are advised to consume glucose-electrolyte solutions. For patients with moderately elevated stoma output (1–1.5 L/day), fluid intake restriction (<1.5 L/day) and dietary salt supplementation can help compensate for sodium loss.²⁹

Limiting the intake of foods high in simple sugars (eg, candy, honey, jam, jelly) and high-sugar beverages (eg, fruit juices, sodas) can reduce stoma output and mitigate the risk of dehydration.¹⁰ Ileostomy patients are prone to both dehydration and impaired sodium and potassium absorption. Therefore, the consumption of fluids containing electrolytes (sodium and potassium) with low sugar content is recommended.^10,28

Adequate fluid intake is crucial for ileostomy patients to maintain fluid balance. Therefore, it is recommended that these patients increase their daily fluid intake by at least 500–750 mL above the average recommended intake for the general population. Preferred fluids include water, broth, vegetable juices, and certain sports drinks. In cases of persistent high stoma output (>1.5 L/day), the use of soluble fiber supplements or antimotility agents should be considered. Soluble fiber can increase the viscosity of intestinal contents, while antimotility drugs slow intestinal transit time, both of which can thicken feces and reduce watery output, thereby preventing dehydration and electrolyte imbalances.³²

High-volume liquid stools may lead to leakage and peristomal skin irritation. Patients should be encouraged to consume foods that thicken stool, such as butter, cheese, rice, bananas, pasta, potatoes, noodles, and marshmallows. These foods can help increase output consistency by slowing intestinal transit time.^32,41

Standardizing Dietary Behaviors to Prevent and Manage Postoperative Complications

Ileostomy patients face a higher risk of stoma obstruction compared to colostomy patients due to the smaller diameter of the ileal lumen (<2.5cm). This necessitates specific dietary modifications to mitigate this risk. Patients are advised to consume small quantities of potentially obstructing foods and chew thoroughly. Common “obstructive foods” include popcorn, coconut, mushrooms, black olives, high-fiber vegetables, corn, nuts, celery, foods with skin, dried fruits, and meats with casings. The introduction of new foods should be gradual, beginning 6–8 weeks post-surgery. It is recommended to introduce one new food item every three days in small quantities, while monitoring for any adverse reactions. This approach allows for a gradual increase in dietary variety while minimizing the risk of stoma obstruction.³¹

Intestinal gas in ileostomy patients can result from the consumption of gas-producing foods, carbonated beverages, and certain dietary behaviors.²¹ It is advisable to limit or avoid gas-producing foods such as carbonated drinks, legumes, onions, beer, spinach, bean sprouts, and coffee. Patients should also avoid using straws, talking while eating, and chewing gum to reduce air ingestion. Maintaining regular meal times and avoiding long intervals between meals can help reduce gas production.²¹

Consuming smaller, more frequent meals throughout the day can help reduce stoma output. A balanced diet encompassing a variety of fruits, vegetables, lean proteins, and grains is crucial to ensure adequate nutrition.²¹ Hydration between meals, rather than with meals, can reduce the risk of stoma obstruction. Limiting fluid intake 30 minutes before and after meals, and avoiding rapid water consumption with meals, can help manage stoma output.²⁹ Consuming larger portions at breakfast and lunch, with a lighter dinner and restricted evening fluid intake, can reduce nocturnal stoma output and improve sleep quality.¹⁰

Vitamins and trace elements play vital roles in maintaining normal metabolism, physiological functions, and promoting growth and development. Due to the lack of colonic reabsorption and high stoma output, ileostomy patients may not obtain sufficient micronutrients from their diet alone. Therefore, oral supplementation with multivitamins and minerals such as iron, calcium, liquid magnesium, zinc, manganese, and selenium is recommended to prevent malnutrition due to micronutrient deficiencies.²⁸

Emphasize Health Education and Enhance Follow-Up Care

The majority of ileostomy patients with nutritional risks or malnutrition are unable to fully improve their nutritional status during short hospital stays, with many still experiencing malnutrition at discharge. Therefore, it is recommended that patients with postoperative nutritional risks or malnutrition continue to receive nutritional therapy for 4–8 weeks post-discharge. The use of standard formula oral nutritional supplements (ONS) is advised, along with regular follow-ups and monitoring of nutritional status.^25,26 Nutritionists or specialized stoma nurses should provide nutritional counseling to patients.³⁸

Stoma specialist nurses should intensify follow-up care, with a recommendation for continuous monitoring of intake and stoma output for 4 weeks to reduce the risk of dehydration and electrolyte imbalances. Concurrently, healthcare professionals should prioritize patient education prior to discharge. Patients and their families should be informed about the importance of adequate daily fluid intake. They should be taught how to accurately record intake/stoma output and recognize signs and symptoms of dehydration and fluid-electrolyte imbalances. The importance of seeking prompt treatment when these symptoms occur should be emphasized to mitigate the risk of fluid-electrolyte imbalances.¹⁸

Conclusion

This study synthesizes the current best evidence for the dietary management of patients with high-output ileostomies, emphasizing a systematic approach that includes nutritional risk screening, postoperative monitoring, dietary guidance, and follow-up care. This evidence-based process aims to standardize the dietary management, thereby improving patient outcomes and quality of life.