Preoperative Enteral Nutrition and Surgical Outcomes in Adults with Crohn's Disease: A Systematic Review

AGA Clinical Practice Update on Diet and Nutritional Therapies in Patients With Inflammatory Bowel Disease: Expert Review

DESCRIPTION

Diet plays a critical role in human health, but especially for patients with inflammatory bowel disease (IBD). Guidance about diet for patients with IBD are often controversial and a source of uncertainty for many physicians and patients. The role of diet has been investigated as a risk factor for IBD etiopathogenesis and as a therapy for active disease. Dietary restrictions, along with the clinical complications of IBD, can result in malnutrition, an underrecognized condition among this patient population. The aim of this American Gastroenterological Association (AGA) Clinical Practice Update (CPU) is to provide best practice advice statements, primarily to clinical gastroenterologists, covering the topics of diet and nutritional therapies in the management of IBD, while emphasizing identification and treatment of malnutrition in these patients. We provide guidance for tailored dietary approaches during IBD remission, active disease, and intestinal failure. A healthy Mediterranean diet will benefit patients with IBD, but may require accommodations for food texture in the setting of intestinal strictures or obstructions. New data in Crohn's disease supports the use of enteral liquid nutrition to help induce remission and correct malnutrition in patients heading for surgery. Parenteral nutrition plays a critical role in patients with IBD facing acute and/or chronic intestinal failure. Registered dietitians are an essential part of the interdisciplinary team approach for optimal nutrition assessment and management in the patient population with IBD.

METHODS

This expert review was commissioned and approved by the AGA Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPU Committee and external peer review through standard procedures of Gastroenterology. The best practice advice statements were drawn from reviewing existing literature combined with expert opinion to provide practical advice on the role of diet and nutritional therapies in patients with IBD. Because this was not a systematic review, formal rating of the quality of evidence or strength of the presented considerations was not performed. Best Practice Advice Statements BEST PRACTICE ADVICE 1: Unless there is a contraindication, all patients with IBD should be advised to follow a Mediterranean diet rich in a variety of fresh fruits and vegetables, monounsaturated fats, complex carbohydrates, and lean proteins and low in ultraprocessed foods, added sugar, and salt for their overall health and general well-being. No diet has consistently been found to decrease the rate of flares in adults with IBD. A diet low in red and processed meat may reduce ulcerative colitis flares, but has not been found to reduce relapse in Crohn's disease. BEST PRACTICE ADVICE 2: Patients with IBD who have symptomatic intestinal strictures may not tolerate fibrous, plant-based foods (ie, raw fruits and vegetables) due to their texture. An emphasis on careful chewing and cooking and processing of fruits and vegetables to a soft, less fibrinous consistency may help patients with IBD who have concomitant intestinal strictures incorporate a wider variety of plant-based foods and fiber in their diets. BEST PRACTICE ADVICE 3: Exclusive enteral nutrition using liquid nutrition formulations is an effective therapy for induction of clinical remission and endoscopic response in Crohn's disease, with stronger evidence in children than adults. Exclusive enteral nutrition may be considered as a steroid-sparing bridge therapy for patients with Crohn's disease. BEST PRACTICE ADVICE 4: Crohn's disease exclusion diet, a type of partial enteral nutrition therapy, may be an effective therapy for induction of clinical remission and endoscopic response in mild to moderate Crohn's disease of relatively short duration. BEST PRACTICE ADVICE 5: Exclusive enteral nutrition may be an effective therapy in malnourished patients before undergoing elective surgery for Crohn's disease to optimize nutritional status and reduce postoperative complications. BEST PRACTICE ADVICE 6: In patients with IBD who have an intra-abdominal abscess and/or phlegmonous inflammation that limits ability to achieve optimal nutrition via the digestive tract, short-term parenteral nutrition may be used to provide bowel rest in the preoperative phase to decrease infection and inflammation as a bridge to definitive surgical management and to optimize surgical outcomes. BEST PRACTICE ADVICE 7: We suggest the use of parenteral nutrition for high-output gastrointestinal fistula, prolonged ileus, short bowel syndrome, and for patients with IBD with severe malnutrition when oral and enteral nutrition has been trialed and failed or when enteral access is not feasible or contraindicated. BEST PRACTICE ADVICE 8: In patients with IBD and short bowel syndrome, long-term parenteral nutrition should be transitioned to customized hydration management (ie, intravenous electrolyte support and/or oral rehydration solutions) and oral intake whenever possible to decrease the risk of developing long-term complications. Treatment with glucagon-like peptide-2 agonists can facilitate this transition. BEST PRACTICE ADVICE 9: All patients with IBD warrant regular screening for malnutrition by their provider by means of assessing signs and symptoms, including unintended weight loss, edema and fluid retention, and fat and muscle mass loss. When observed, more complete evaluation for malnutrition by a registered dietitian is indicated. Serum proteins are no longer recommended for the identification and diagnosis of malnutrition due to their lack of specificity for nutritional status and high sensitivity to inflammation. BEST PRACTICE ADVICE 10: All patients with IBD should be monitored for vitamin D and iron deficiency. Patients with extensive ileal disease or prior ileal surgery (resection or ileal pouch) should be monitored for vitamin B12 deficiency. BEST PRACTICE ADVICE 11: All outpatients and inpatients with complicated IBD warrant co-management with a registered dietitian, especially those who have malnutrition, short bowel syndrome, enterocutaneous fistula, and/or are requiring more complex nutrition therapies (eg, parenteral nutrition, enteral nutrition, or exclusive enteral nutrition), or those on a Crohn's disease exclusion diet. We suggest that all newly diagnosed patients with IBD have access to a registered dietitian. BEST PRACTICE ADVICE 12: Breastfeeding is associated with a lower risk for diagnosis of IBD during childhood. A healthy, balanced, Mediterranean diet rich in a variety of fruits and vegetables and decreased intake of ultraprocessed foods have been associated with a lower risk of developing IBD.

Perioperative nutrition in the setting of pediatric inflammatory bowel disease

BACKGROUND

Optimization of nutrition prior to inflammatory bowel disease (IBD)-related surgery could improve outcomes. The aim of this study was to assess the perioperative nutrition status and management of children undergoing intestinal resection for treatment of their IBD.

METHODS

We identified all patients with IBD who underwent primary intestinal resection. We identified malnutrition using established criteria and methods of nutrition provision at various time points (preoperative outpatient evaluation, admission, and postoperative outpatient follow-up) for elective cases (who underwent their procedure at a scheduled admission) and urgent cases (who underwent an unplanned surgical intervention). We also recorded data on postsurgical complications.

RESULTS

A total of 84 patients were identified in this single-center study (male sex: 40%, mean age: 14.5 years, Crohn's disease: 65%). Thirty-four patients (40%) had some degree of malnutrition. Prevalence of malnutrition in the urgent and elective cohorts was similar (48% vs 36%; P = 0.37). Of these patients, 29 (34%) were noted to be on some type of nutrition supplementation prior to surgery. Postoperatively, BMI z scores increased (-0.61 vs -0.42; P = 0.0008), but the percentage of patients who were malnourished did not change from preoperative status (40% vs 40%; P = 0.10). Despite this, use of nutrition supplementation was only noted in 15 (17%) patients at postoperative follow-up. Complications were not associated with nutrition status.

CONCLUSION

Utilization of supplemental nutrition decreased postprocedure despite no change in malnutrition prevalence. These findings support the development of a pediatric-specific perioperative nutrition protocol in the setting of IBD-related surgery.

Preoperative Exclusive Enteral Nutrition Is Associated With Reduced Skin and Soft Tissue and Intra-abdominal Infections in Patients With Crohn's Disease Undergoing Intestinal Surgery: Results from a Meta-Analysis

BACKGROUND

Malnutrition is an independent risk factor for adverse postoperative outcomes and is common among patients with Crohn's disease (CD). The objective of this meta-analysis was to precisely quantify the association of preoperative exclusive enteral nutrition (EEN) and total parenteral nutrition (TPN) with surgical outcomes in patients undergoing intestinal surgery for CD.

METHODS

PubMed, Embase, and Scopus were queried for comparative studies evaluating the impact of preoperative nutritional support on postoperative outcomes in patients undergoing surgery for CD. Random effects modeling was used to compute pooled estimates of risk difference. Heterogeneity was assessed using I2.

RESULTS

Fourteen studies, all nonrandomized cohort studies, met inclusion criteria for studying EEN. After pooling data from 14 studies (874 EEN treated and 1044 control patients), the relative risk of intra-abdominal septic complications was decreased 2.1-fold in patients receiving preoperative EEN (relative risk 0.47, 95% confidence interval [CI], 0.35-0.63, I2 = 0.0%). After pooling data from 9 studies (638 EEN treated and 819 control patients), the risk of skin and soft tissue infection was decreased 1.6-fold (relative risk 0.63; 95% CI, 0.42-0.94, I2 = 42.7%). No significant differences were identified in duration of surgery, length of bowel resected, or operative blood loss. Among the 9 studies investigating TPN, no significant differences were identified in infectious outcomes.

CONCLUSIONS

Preoperative nutritional optimization with EEN was associated with reduced risk of infectious complications in CD patients undergoing intestinal surgery. Preoperative nutritional support with EEN should be considered for optimizing outcomes in CD patients requiring bowel resection surgery.

ECCO Topical Review: Roadmap to Optimal Peri-Operative Care in IBD

BACKGROUND AND AIMS

Despite the advances in medical therapies, a significant proportion of patients with inflammatory bowel diseases [IBD] require surgical intervention. This Topical Review aims to offer expert consensus practice recommendations for peri-operative care to optimize outcomes of IBD patients who undergo surgery.

METHODS

A multidisciplinary panel of IBD healthcare providers systematically reviewed aspects relevant to peri-operative care in IBD. Consensus statements were developed using Delphi methodology.

RESULTS

A total of 20 current practice positions were developed following systematic review of the current literature covering use of medication in the peri-operative period, nutritional assessment and intervention, physical and psychological rehabilitation and prehabilitation, and immediate postoperative care.

CONCLUSION

Peri-operative planning and optimization of the patient are imperative to ensure favourable outcomes and reduced morbidity. This Topical Review provides practice recommendations applicable in the peri-operative period in IBD patients undergoing surgery.

British Dietetic Association consensus guidelines on the nutritional assessment and dietary management of patients with inflammatory bowel disease

BACKGROUND

Despite increased awareness of diet and nutrition being integral to the management of patients with inflammatory bowel disease (IBD), there are gaps in the knowledge of IBD healthcare providers regarding nutrition. Furthermore, high quality evidence on nutritional assessment and dietary management of IBD is limited. A Delphi consensus from a panel of experts allows for best-practice guidelines to be developed, especially where high quality evidence is limited. The aim was to develop guidelines for the nutritional assessment and dietary management of IBD using an eDelphi online consensus agreement platform.

METHODS

Seventeen research topics related to IBD and nutrition were systematically reviewed. Searches in Cochrane, Embase®, Medline® and Scopus® electronic databases were performed. GRADE was used to develop recommendations. Experts from the IBD community (healthcare professionals and patients with IBD) were invited to vote anonymously on the recommendations in a custom-built online platform. Three rounds of voting were carried out with updated iterations of the recommendations and evaluative text based on feedback from the previous round.

RESULTS

From 23,824 non-duplicated papers, 167 were critically appraised. Fifty-five participants completed three rounds of voting and 14 GRADE statements and 42 practice statements achieved 80% consensus. Comprehensive guidance related to nutrition assessment, nutrition screening and dietary management is provided.

CONCLUSIONS

Guidelines on the nutritional assessment and dietary management of IBD have been developed using evidence-based consensus to improve equality of care. The statements and practice statements developed demonstrate the level of agreement and the quality and strength of the guidelines.

A retrospective cohort study: pre-operative oral enteral nutritional optimisation for Crohn's disease in a UK tertiary IBD centre

BACKGROUND

Low-quality evidence suggests that pre-operative exclusive enteral nutrition (E/EN) can improve postoperative outcomes in patients with Crohn's disease (CD). It is not standard practice in most centres.

AIMS

To test the hypothesis that pre-operative EN in patients undergoing ileal/ileocolonic surgery for CD is associated with improved postoperative outcome.

METHODS

We performed a single centre retrospective observational study comparing surgical outcomes in patients receiving pre-operative EN (≥600 kcal/day for ≥2 weeks) with those who received no nutritional optimisation. Consecutive adult patients undergoing ileal/ileocolonic resection from 2008 to 2020 were included. The primary outcome was postoperative complications <30 days. Secondary outcomes included EN tolerance, specific surgical complications, unplanned stoma formation, length of stay, length of bowel resected, readmission and biochemical/anthropometric changes.

RESULTS

300 surgeries were included comprising 96 without nutritional optimisation and 204 optimised cases: oral EN n = 173, additional PN n = 31 (4 of whom had received nasogastric/nasojejunal EN). 142/204 (69.6%) tolerated EN. 125/204 (61.3%) initiated EN in clinic. Patients in the optimised cohort were younger at operation and diagnosis, with an increased frequency of penetrating disease and exposure to antibiotics or biologics, and were more likely to undergo laparoscopic surgery. The optimised cohort had favourable outcomes on multivariate analysis: all complications [OR 0.29; 0.15-0.57, p < 0.001], surgical complications [OR 0.41; 95% CI 0.20-0.87, p = 0.02], non-surgical complications [OR 0.24 95% CI 0.11-0.52, p < 0.001], infective complications [OR 0.32; 95% CI 0.16-0.66, p = 0.001].

CONCLUSIONS

Oral EN was reasonably well tolerated and associated with a reduction in 30-day postoperative complications. Randomised controlled trials are required to confirm these findings.

Prehabilitation in adult patients undergoing surgery: an umbrella review of systematic reviews

BACKGROUND

The certainty that prehabilitation improves postoperative outcomes is not clear. The objective of this umbrella review (i.e. systematic review of systematic reviews) was to synthesise and evaluate evidence for prehabilitation in improving health, experience, or cost outcomes.

METHODS

We performed an umbrella review of prehabilitation systematic reviews. MEDLINE, Embase, Cochrane, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, Joanna Briggs Institute's database, and Web of Science were searched (inception to October 20, 2020). We included all systematic reviews of elective, adult patients undergoing surgery and exposed to a prehabilitation intervention, where health, experience, or cost outcomes were reported. Evidence certainty was assessed using Grading of Recommendations Assessment, Development and Evaluation. Primary syntheses of any prehabilitation were stratified by surgery type.

RESULTS

From 1412 titles, 55 systematic reviews were included. For patients with cancer undergoing surgery who participate in any prehabilitation, moderate certainty evidence supports improvements in functional recovery. Low to very low certainty evidence supports reductions in complications (mixed, cardiovascular, and cancer surgery), non-home discharge (orthopaedic surgery), and length of stay (mixed, cardiovascular, and cancer surgery). There was low to very low certainty evidence that exercise prehabilitation reduces the risk of complications, non-home discharge, and length of stay. There was low to very low certainty evidence that nutritional prehabilitation reduces risk of complications, mortality, and length of stay.

CONCLUSIONS

Low certainty evidence suggests that prehabilitation may improve postoperative outcomes. Future low risk of bias, randomised trials, synthesised using recommended standards, are required to inform practice. Optimal patient selection, intervention design, and intervention duration must also be determined.

Effect of Pre-operative Nutritional Protocol Implementation on Postoperative Outcomes Following Gastrointestinal Surgeries: A Randomized Clinical Trial

Introduction: A significant proportion of patients undergoing major gastrointestinal operations suffer from malnutrition. Although the benefit of postoperative nutritional support is well established, the effects of energy intake during pre-operative period is less reported. The present study was designed to test the effect of structured pre-operative nutritional therapy on the postoperative recovery of patients undergoing major gastrointestinal operations.

Methods: A randomized clinical trial was conducted among 80 patients of the surgical gastroenterology department of a tertiary care center in south India. A simple random sampling method was used. The nutritional status of all participants was assessed by subjective global assessment (SGA). While control group received standard energy intake nutrition, the experimental group received calculated nutrition with an extra 50 g of soy protein for seven days pre operatively. Data were analysed using SPSS version 20.

Results: The median day of removal of abdominal drainage tube was 3 (0-5) compared to 5 (2.5-7.5) in the control group. In the intervention group, the median time for the appearance of bowel sounds and starting of enteral feeding was 1.1 (0.5) days and 2 (1-2) days, while in the control group, it was 1.6 (0.9) days, 3 (1-4) days, respectively which was significant at P < 0.05. Similarly, the mean (SD) postoperative serum albumin on third day was 3.6 (0.4) g/dL vs 3.4 (0.4) g/dL experimental and in the control group.

Conclusion: Preoperative nutrition protocol improved the patients’ clinical outcomes in terms of post-operative serum albumin, the timing of bowel sounds, and early initiation of enteral feeds.

Sarcopenia hinders the decline in disease activity after surgery for people with Crohn's disease: Preliminary results

OBJECTIVES

Surgical treatment is an important option for inducing remission in Crohn's disease (CD); indeed, the longer the disease duration, the higher the cumulative surgical rate. Previous studies have shown that the pathogenesis of Crohn's disease is associated with sarcopenia, a condition of reduced skeletal muscle mass. Here, we investigated the effect of preoperative sarcopenia on postoperative disease activity.

METHODS

This retrospective study included 56 patients with CD with medical records who met our inclusion criteria. Sarcopenia was diagnosed based on the psoas muscle mass index derived from computed tomography images, with predetermined cutoff values of <6.36 cm²/m² for men and <3.92 cm²/m² for women. We performed univariate and multivariate analyses to identify factors associated with sarcopenia.

RESULTS

Of the 56 participants, nine (16%) had sarcopenia. The rate of preoperative treatment with biological drugs was significantly lower in the sarcopenia group than the non-sarcopenia group. In addition, the operation time was significantly longer, and hemorrhage occurred more often, in the sarcopenia group than in the non-sarcopenia group. Postoperatively, the CD activity index at 6 mo had significantly decreased in the non-sarcopenia group (P = 0.01) but not in the sarcopenia group (P = 0.20). Univariate and multivariate analyses showed that a low total serum protein level was significantly associated with sarcopenia.

CONCLUSION

Our results suggest that to maximize the effect of surgical treatment for CD, an appropriate nutritional intervention should be performed before surgery, or surgery should be postponed until after the patient recovers from sarcopenia.

Does exclusive enteral nutrition reduce the rate of stoma formation in patients requiring ileocolic resection for Crohn's disease? A single center experience

BACKGROUND AND AIM

Nutrition has a role in achieving and maintaining remission in Crohn's disease. The aim of this study was to determine the impact of a strategy of steroid-avoidance and Exclusive Enteral Nutrition (EEN) for 6 weeks (with a minimum of 4 weeks) in adult patients presenting with acute small bowel Crohn's disease followed by an interval ileocolic resection 4-6 weeks later.

METHODS

Retrospective review of prospectively collected data. Patients were administered exclusive enteral nutrition (EEN) for at least 4 weeks prior to surgery.

RESULTS

24 EEN patients included. Median age of 45 (range 23-73). 17/24 patients tolerated Modulen for at least 4 weeks, 5 were switched to Ensures and 2 a liquid diet. 6 patients underwent surgery earlier than planned. Prior to surgery, there was no change in the mean BMI, albumin increased from a mean of 36 g/L (range 25-43) to 40 g/L (range 30-48). CRP levels decreased by a mean of 35.8 mg/L overall. 19 (79%) of operations were performed laparoscopically. 6 of the cases were re-do operations. All but 3 patients avoided a stoma at the time of the original operation. There were 5 post-operative complications: 1 anastomotic leak in a patient with a BMI of 42, 3 cases of paralytic ileus and 2 wound infections. Median length of stay was 7 days (range 3-76 days). Only 2 patients were readmitted within the 30-day post-operative period.

CONCLUSION

The pre-operative use of EEN appears to avoid unnecessary stoma formation with acceptable clinical outcomes.

EEN Yesterday and Today … CDED Today and Tomorrow

The treatment of Pediatric Crohn’s Disease (CD) requires attention both to achieve mucosal healing and to optimize growth, while also maintaining proper bone health. Exclusive Enteral Nutrition (EEN) is recommended as first-line treatment in luminal CD. The therapeutic mechanisms of EEN are being discovered by advances in the study of the gut microbiota. Although the total exclusion of a normal diet during the time of EEN continues to be of high importance, new modalities of dietary treatment suggest a successful future for the nutritional management of CD. In this sense, Crohn’s Disease Exclusion Diet (CDED) is a long-term strategy, it apparently acts on the mechanisms that influence the appearance of inflammation (reducing dietary exposure to products negatively affecting the microbiota), but does so using specific available whole foods to achieve this goal, increases the time of clinical remission and promotes healthy lifestyle habits. The development of CDED, which partly minimizes the problems of EEN, has enabled a turnaround in the treatment of pediatric CD. This review highlights the role of enteral nutrition in the treatment of Crohn’s disease with special emphasis on newer dietary modalities such as CDED.

Prehabilitation: The Impact of Preoperative Exclusive Enteral Nutrition on Paediatric Patients With Crohn Disease

Exclusive enteral nutrition (EEN) is effective in inducing remission in paediatric Crohn Disease (CD) and has been shown to reduce inflammation and improve outcomes in adult CD patients when used before resectional surgery. This retrospective study demonstrates that preoperative EEN is achievable in paediatric CD patients undergoing right hemicolectomy and is associated with positive peri-operative outcomes. Seventeen patients (8 who received preoperative EEN and 9 who did not) were included in the study. Six of 8 (75.0%) managed EEN orally; 1 via nasogastric tube and another via a previously sited gastrostomy. Use of preoperative EEN was associated with a decreased rate of moderate/severe disease on resection pathology (5/8 [62.5%] vs 9/9 [100%]; P = 0.04). Larger studies are required to determine the wider potential benefits of preoperative EEN on postoperative outcomes within paediatric practice.

Enteral Nutrition in Adult Crohn's Disease: Toward a Paradigm Shift

Medical and surgical treatments for Crohn's disease are associated with toxic effects. Medical therapy aims for mucosal healing and is achievable with biologics, immunosuppressive therapy, and specialised enteral nutrition, but not with corticosteroids. Sustained remission remains a therapeutic challenge. Enteral nutrition, containing macro- and micro-nutrients, is nutritionally complete, and is provided in powder or liquid form. Enteral nutrition is a low-risk and minimally invasive therapy. It is well-established and recommended as first line induction therapy in paediatric Crohn's disease with remission rates of up to 80%. Other than in Japan, enteral nutrition is not routinely used in the adult population among Western countries, mainly due to unpalatable formulations which lead to poor compliance. This study aims to offer a comprehensive review of available enteral nutrition formulations and the literature supporting the use and mechanisms of action of enteral nutrition in adult Crohn's disease patients, in order to support clinicians in real world decision-making when offering/accepting treatment. The mechanisms of actions of enteral feed, including their impact on the gut microbiome, were explored. Barriers to the use of enteral nutrition, such as compliance and the route of administration, were considered. All available enteral preparations have been comprehensively described as a practical guide for clinical use. Likewise, guidelines are reported and discussed.