Effect of fiber supplementation on the microbiota in critically ill patients

The Microbiome in Critical Illness

Evidence suggests that the intestinal microbiome may play an important role in the pathogenesis and progression of acute critical illness in humans and other mammals, although evidence in small animal medicine is sparse. Moreover, the intestinal microbiota plays many important metabolic roles (production of short-chain fatty acids, trimethylamine-N-oxide, and normal bile acid metabolism) and is crucial for immunity as well as defense against enteropathogens. The use of probiotics and fecal microbiota transplantation as instruments to modulate the intestinal microbiota seems to be safe and effective in studies on critically ill dogs with acute gastrointestinal diseases.

Effect of dietary fibre on the gastrointestinal microbiota during critical illness: A scoping review

The systemic effects of gastrointestinal (GI) microbiota in health and during chronic diseases is increasingly recognised. Dietary strategies to modulate the GI microbiota during chronic diseases have demonstrated promise. While changes in dietary intake can rapidly change the GI microbiota, the impact of dietary changes during acute critical illness on the microbiota remain uncertain. Dietary fibre is metabolised by carbohydrate-active enzymes and, in health, can alter GI microbiota. The aim of this scoping review was to describe the effects of dietary fibre supplementation in health and disease states, specifically during critical illness. Randomised controlled trials and prospective cohort studies that include adults (> 18 years age) and reported changes to GI microbiota as one of the study outcomes using non-culture methods, were identified. Studies show dietary fibres have an impact on faecal microbiota in health and disease. The fibre, inulin, has a marked and specific effect on increasing the abundance of faecal Bifidobacteria. Short chain fatty acids produced by Bifidobacteria have been shown to be beneficial in other patient populations. Very few trials have evaluated the effect of dietary fibre on the GI microbiota during critical illness. More research is necessary to establish optimal fibre type, doses, duration of intervention in critical illness.

The efficacy of fiber-supplemented enteral nutrition in critically ill patients: a systematic review and meta-analysis of randomized controlled trials with trial sequential analysis

BACKGROUND

Evidence on the benefits of fiber-supplemented enteral nutrition (EN) in critically ill patients is inconsistent, and critical care nutrition guidelines lack recommendations based on high-quality evidence. This systematic review and meta-analysis (SRMA) aims to provide a current synthesis of the literature on this topic.

METHODS

For this SRMA of randomized controlled trials (RCT), electronic databases (MEDLINE, EMBASE, CENTRAL) were searched systematically from inception to January 2024 and updated in June 2024. Trials investigating clinical effects of fiber-supplemented EN versus placebo or usual care in adult critically ill patients were selected. Two independent reviewers extracted data and assessed the risk of bias of the included studies. Random-effect meta-analysis and trial sequential analysis (TSA) were conducted. The primary outcome was overall mortality, and one of the secondary outcomes was diarrhea incidence. Subgroup analyses were also performed for both outcomes.

RESULTS

Twenty studies with 1405 critically ill patients were included. In conventional meta-analysis, fiber-supplemented EN was associated with a significant reduction of overall mortality (RR 0.66, 95% CI 0.47, 0.92, p = 0.01, I2 = 0%; 12 studies) and diarrhea incidence (RR 0.70, 95% CI 0.51, 0.96, p = 0.03, I2 = 51%; 11 studies). However, both outcomes were assessed to have very serious risk of bias, and, according to TSA, a type-1 error cannot be ruled out. No subgroup differences were found for the primary outcome.

CONCLUSION

Very low-certainty evidence suggests that fiber-supplemented EN has clinical benefits. High-quality multicenter RCTs with large sample sizes are needed to substantiate any firm recommendation for its routine use in this group of patients. PROSPERO registration number: CRD42023492829.

Role of gut microbiota and bacterial translocation in acute intestinal injury and mortality in patients admitted in ICU for septic shock

Introduction

Sepsis is a life-threatening organ dysfunction with high mortality rate. The gut origin hypothesis of multiple organ dysfunction syndrome relates to loss of gut barrier function and the ensuing bacterial translocation. The aim of this study was to describe the evolution of gut microbiota in a cohort of septic shock patients over seven days and the potential link between gut microbiota and bacterial translocation.

Methods

Sixty consecutive adult patients hospitalized for septic shock in intensive care units (ICU) were prospectively enrolled. Non-inclusion criteria included patients with recent or scheduled digestive surgery, having taken laxatives, pre- or probiotic in the previous seven days, a progressive digestive neoplasia, digestive lymphoma, chronic inflammatory bowel disease, moribund patient, and pregnant and lactating patients. The primary objective was to evaluate the evolution of bacterial diversity and richness of gut microbiota during seven days in septic shock. Epidemiological, clinical and biological data were gathered over seven days. Gut microbiota was analyzed through a metagenomic approach. 100 healthy controls were selected among healthy blood donors for reference basal 16S rDNA values.

Results

Significantly lower bacterial diversity and richness was observed in gut microbiota of patients at Day 7 compared with Day 0 (p<0.01). SOFA score at Day 0, Acute Gastrointestinal Injury (AGI) local grade, septic shock origin and bacterial translocation had an impact on alpha diversity. A large increase in Enterococcus genus was observed at Day 7 with a decrease in Enterobacterales, Clostridiales, Bifidobacterium and other butyrate-producing bacteria.

Discussion

This study shows the importance of bacterial translocation during AGI in septic shock patients. This bacterial translocation decreases during hospitalization in ICUs in parallel to the decrease of microbiota diversity. This work highlights the role of gut microbiota and bacterial translocation during septic shock.

Causal associations of gut microbiota and metabolites on sepsis: a two-sample Mendelian randomization study

Background

Sepsis stands as a dire medical condition, arising when the body's immune response to infection spirals into overdrive, paving the way for potential organ damage and potential mortality. With intestinal flora's known impact on sepsis but a dearth of comprehensive data, our study embarked on a two-sample Mendelian randomization analysis to probe the causal link between gut microbiota and their metabolites with severe sepsis patients who succumbed within a 28-day span.

Methods

Leveraging data from Genome-wide association study (GWAS) and combining it with data from 2,076 European descendants in the Framingham Heart Study, single-nucleotide polymorphisms (SNPs) were employed as Instrumental Variables (IVs) to discern gene loci affiliated with metabolites. GWAS summary statistics for sepsis were extracted from the UK Biobank consortium.

Results

In this extensive exploration, 93 distinct genome-wide significant SNPs correlated with gut microbial metabolites and specific bacterial traits were identified for IVs construction. Notably, a substantial link between Coprococcus2 and both the incidence (OR of 0.80, 95% CI: 0.68-0.94, P=0.007) and the 28-day mortality rate (OR 0.48, 95% CI: 0.27-0.85, P=0.013) of sepsis was observed. The metabolite α-hydroxybutyrate displayed a marked association with sepsis onset (OR=1.08, 95% CI: 1.02-1.15, P=0.006) and its 28-day mortality rate (OR=1.17, 95% CI: 1.01-1.36, P=0.029).

Conclusion

This research unveils the intricate interplay between the gut microbial consortium, especially the genus Coprococcus, and the metabolite α-hydroxybutyrate in the milieu of sepsis. The findings illuminate the pivotal role of intestinal microbiota and their metabolites in sepsis' pathogenesis, offering fresh insights for future research and hinting at novel strategies for sepsis' diagnosis, therapeutic interventions, and prognostic assessments.

The Role of Short-Chain Fatty Acids in Acute Pancreatitis

Acute pancreatitis (AP) is a digestive emergency and can develop into a systematic illness. The role of the gut in the progression and deterioration of AP has drawn much attention from researchers, and areas of interest include dysbiosis of the intestinal flora, weakened intestinal barrier function, and bacterial and endotoxin translocation. Short-chain fatty acids (SCFAs), as one of the metabolites of gut microbiota, have been proven to be depleted in AP patients. SCFAs help restore gut homeostasis by rebuilding gut flora, stabilizing the intestinal epithelial barrier, and regulating inflammation. SCFAs can also suppress systematic inflammatory responses, improve the injured pancreas, and prevent and protect other organ dysfunctions. Based on multiple beneficial effects, increasing SCFAs is an essential idea of gut protective treatment in AP. Specific strategies include the direct use of butyrate or indirect supplementation through fiber, pre/pro/synbiotics, or fecal microbiota transplantation as a promising adjective therapy to enteral nutrition.

[Immunomodulation by nutritional intervention in critically ill patients]

Critically ill patients often suffer from a complex and severe immunological dysfunction. The differentiation and function of human immune cells are fundamentally controlled through metabolic processes. New concepts of immunonutrition therefore try to use enteral and parenteral nutrition to positively impact on the immune function of intensive care unit patients. This review article concisely presents the currently available evidence on the commonly used isolated supplements (anti-oxidative substances, amino acids, essential fatty acids) and difficulties related to their clinical use. The second part presents new and more comprehensive concepts of immunonutrition to influence the intestinal microbiome and to modulate the macronutrient composition. Immunonutrition of critically ill patients bears enormous potential and could become a valuable clinical tool for modulation of the immunometabolism of intensive care unit patients.

The central and biodynamic role of gut microbiota in critically ill patients

Gut microbiota plays an essential role in health and disease. It is constantly evolving and in permanent communication with its host. The gut microbiota is increasingly seen as an organ, and its failure, reflected by dysbiosis, is seen as an organ failure associated with poor outcomes. Critically ill patients may have an altered gut microbiota, namely dysbiosis, with a severe reduction in "health-promoting" commensal intestinal bacteria (such as Firmicutes or Bacteroidetes) and an increase in potentially pathogenic bacteria (e.g. Proteobacteria). Many factors that occur in critically ill patients favour dysbiosis, such as medications or changes in nutrition patterns. Dysbiosis leads to several important effects, including changes in gut integrity and in the production of metabolites such as short-chain fatty acids and trimethylamine N-oxide. There is increasing evidence that gut microbiota and its alteration interact with other organs, highlighting the concept of the gut-organ axis. Thus, dysbiosis will affect other organs and could have an impact on the progression of critical diseases. Current knowledge is only a small part of what remains to be discovered. The precise role and contribution of the gut microbiota and its interactions with various organs is an intense and challenging research area that offers exciting opportunities for disease prevention, management and therapy, particularly in critical care where multi-organ failure is often the focus. This narrative review provides an overview of the normal composition of the gut microbiota, its functions, the mechanisms leading to dysbiosis, its consequences in an intensive care setting, and highlights the concept of the gut-organ axis.

Opioids and Sepsis: Elucidating the Role of the Microbiome and microRNA-146

Sepsis has recently been defined as life-threatening organ dysfunction caused by the dysregulated host response to an ongoing or suspected infection. To date, sepsis continues to be a leading cause of morbidity and mortality amongst hospitalized patients. Many risk factors contribute to development of sepsis, including pain-relieving drugs like opioids, which are frequently prescribed post-operatively. In light of the opioid crisis, understanding the interactions between opioid use and the development of sepsis has become extremely relevant, as opioid use is associated with increased risk of infection. Given that the intestinal tract is a major site of origin of sepsis-causing microbes, there has been an increasing focus on how alterations in the gut microbiome may predispose towards sepsis and mediate immune dysregulation. MicroRNAs, in particular, have emerged as key modulators of the inflammatory response during sepsis by tempering the immune response, thereby mediating the interaction between host and microbiome. In this review, we elucidate contributing roles of microRNA 146 in modulating sepsis pathogenesis and end with a discussion of therapeutic targeting of the gut microbiome in controlling immune dysregulation in sepsis.

Safety of Using Enteral Nutrition Formulations Containing Dietary Fiber in Hospitalized Critical Care Patients: A Systematic Review and Meta-Analysis

Enteral nutrition (EN) is the preferred route of nutrition support for patients with critical illness undergoing intensive care. Experts in the field caution against using fiber during EN because of perceived adverse patient outcomes; however, a comprehensive assessment of this topic is not evident to date. In this systematic review and meta-analysis, we searched four databases from inception to April 20, 2020, for studies on adverse events or health outcomes associated with using EN formulations containing fiber in hospitalized adults with critical illness. Nineteen articles were included. Random-effects meta-analysis models showed significantly lower diarrhea scores for fiber groups compared with nonfiber groups (pooled mean difference: -2.78; 95% CI, -4.10 to -1.47) but mixed results for risk of diarrhea between groups, depending on measures used for diarrhea (Hart and Dobb scale, pooled risk ratio [RR]: 0.68; 95% CI, 0.45-1.02; other diarrhea scales, pooled RR: 0.42; 95% CI, 0.20-0.89). Models showed 39% lower risk of gastrointestinal (GI) complications overall for fiber compared with nonfiber groups (pooled RR: 0.61; 95% CI, 0.47-0.79) but no group differences for individual GI complications, mortality, and intensive care unit or hospital length of stay. Analyses stratified by soluble- or mixed-fiber interventions reduced heterogeneity in models but showed identical conclusions. EN formulas with fiber may help reduce incidence and severity of diarrhea and GI complications overall in critically ill patients, without increased risk of other adverse events. Bias among specific GI measures indicates more high-quality studies are needed to verify these conclusions.

The role of butyrate in surgical and oncological outcomes in colorectal cancer

Butyrate is a short-chain fatty acid produced by colonic gut bacteria as a result of fermentation of dietary fibers. In the colon, butyrate is a major energy substrate and contributes to the nutritional support and proliferation of a healthy mucosa. It also promotes the intestinal barrier function by enhancing mucus production and tight junctions. In addition to its pro-proliferative effect in healthy colonocytes, butyrate inhibits the proliferation of cancer cells. The antineoplastic effect of butyrate is associated with the inhibitory effect of butyrate on histone deacetylase (HDAC) enzymes, which promote carcinogenesis. Due to the metabolic shift of cancer cells toward glycolysis, unused butyrate accumulates and inhibits procarcinogenic HDACs. In addition, recent studies suggest that butyrate may improve the healing of colonic tissue after surgery in animal models, specifically at the site of reconnection of colonic ends, anastomosis, after surgical resection. Here, we review current evidence on the impact of butyrate on epithelial integrity and colorectal cancer and present current knowledge on data that support its potential applications in surgical practice.

Microbiome changes associated with acute and chronic pancreatitis: A systematic review

BACKGROUND

Altered intestinal microbiota has been reported in pancreatic disorders, however, it remains unclear whether these changes alter the course of disease in patients with acute (AP) and chronic pancreatitis (CP), or whether these disease states alter the environment to enable pathogenic microbial composition changes to occur. We undertook a systematic review to characterize the gut microbiome in pancreatitis patients.

METHODS

MEDLINE and EMBASE were searched for studies on microbiota in pancreatitis published from January 1, 2000 to June 5, 2020. Animal studies, reviews, case reports, and non-English articles were excluded. A frequency analysis was performed for outcomes reported in ≥2 studies and studies were analyzed for risk of bias and quality of evidence.

RESULTS

22 papers met inclusion criteria; 15 included AP, 7 included CP. No studies were appropriately designed to assess whether alterations in the gut microbiome exacerbate pancreatitis or develop as a result of pancreatitis. We did identify several patterns of microbiome changes that are associated with pancreatitis. The gut microbiome demonstrated decreased alpha diversity in 3/3 A P studies and 3/3 C P studies. Beta diversity analysis revealed differences in bacterial community composition in the gut microbiome in 2/2 A P studies and 3/3 C P studies. Functionally, gut microbiome changes were associated with infectious pathways in AP and CP. Several studies suffered from high risk of bias and inadequate quality.

CONCLUSIONS

Detecting differences in microbial composition associated with AP and CP may represent a diagnostic tool. Appropriately controlled longitudinal studies are needed to determine whether microbiome changes are causative or reactive in pancreatitis.

Altered Gut Microbiota Taxonomic Compositions of Patients With Sepsis in a Pediatric Intensive Care Unit

Background: The gut is thought to play an important role in the pathogenesis of sepsis. Changes in the gut microbiota are closely related to the occurrence and development of human diseases, but few studies have focused on taxonomic composition of gut microbiota in septic patients. Knowledge of changes in the gut microbiota is a key issue in intensive care. Clinicians must understand how an altered gut microbiota affects the susceptibility and prognosis of septic patients. Measurements and Main Results: In the single-center case control study, 20 septic patients and 20 healthy children were recruited. The taxonomic composition of gut microbiota was determined via 16S rRNA gene sequencing. Gut microbiota diversity in children with sepsis was significantly reduced compared with that in healthy children. The taxonomic composition of gut microbiota can effectively distinguish children with sepsis from healthy children. Thirteen taxa of gut microbiota were significantly increased in the guts of children with sepsis compared with those of healthy children. The increased abundances of Enterococcaceae, Enterococcus, and Enterococcus durans in gut of septic patients were significantly positively correlated with blood inflammation indicators CRP and WBC. The abundances of seven bacteria were significantly decreased in the guts of septic children compared with those of healthy children. The decreased abundance of Bifidobacteriales in gut of septic patients is significantly negatively correlated with blood inflammation index WBC. A machine-learning classifier was built for distinguishing sepsis and achieved the AUC value of 81.25%. It shows that the composition of gut microbiota has certain potential for diagnosis of sepsis. Conclusions: Gut microbiota alterations in septic patients exhibit proliferation of opportunistic pathogenic bacteria, the massive reduction of the commensal flora, and the significant decrease in the diversity of the gut microbiota. Dysbiosis may also account for some changes in the inflammation indexes.

Advanced strategy to exploit wine-making waste by manufacturing antioxidant and prebiotic fibre-enriched vesicles for intestinal health

Grape extract-loaded fibre-enriched vesicles, nutriosomes, were prepared by combining antioxidant extracts obtained from grape pomaces and a prebiotic, soluble fibre (Nutriose®FM06). The nutriosomes were small in size (from ∼140 to 260 nm), homogeneous (polydispersity index < 0.2) and highly negative (∼ -79 mV). The vesicles were highly stable during 12 months of storage at 25 °C. When diluted with warmed (37 °C) acidic medium (pH 1.2) of high ionic strength, the vesicles only displayed an increase of the mean diameter and a low release of the extract, which were dependent on Nutriose concentration. The formulations were highly biocompatible and able to protect intestinal cells (Caco-2) from oxidative stress damage. In vivo results underlined that the composition of mouse microbiota was not affected by the vesicular formulations. Overall results support the potential application of grape nutriosomes as an alternative strategy for the protection of the intestinal tract.

Impact of microbiome-based interventions on gastrointestinal pathogen colonization in the intensive care unit

In the intensive care unit (ICU), colonization of the gastrointestinal tract by potentially pathogenic bacteria is common and often precedes clinical infection. Though effective in the short term, traditional antibiotic-based decolonization methods may contribute to rising resistance in the long term. Novel therapies instead focus on restoring gut microbiome equilibrium to achieve pathogen colonization resistance. This review summarizes the existing data regarding microbiome-based approaches to gastrointestinal pathogen colonization in ICU patients with a focus on prebiotics, probiotics, and synbiotics.

Clinical Multi-Omics Study on the Gut Microbiota in Critically Ill Patients After Cardiovascular Surgery Combined With Cardiopulmonary Bypass With or Without Sepsis (MUL-GM-CSCPB Study): A Prospective Study Protocol

Introduction: Fever of unknown origin (FUO) and hemodynamic instability are complications that develop after cardiac surgery combined with cardiopulmonary bypass (CPB) for heart disease. Patients who develop fever with hemodynamic instability after cardiac surgery may have systemic inflammatory response syndrome or sepsis. Cardiopulmonary bypass (CPB) is a technique that temporarily takes over the function of the heart and lungs during cardiac surgery. Recent reports suggest that early bloodstream infections of patients undergoing CPB are due to gram-negative bacteria that are present in the intestinal flora. The theory of intestinal flora translocation has growing evidence. Intestinal ischemia-reperfusion that occurs during cardiac surgery with CPB will induce a systemic inflammatory reaction and may cause intestinal flora translocation. Does this systemic reaction cause sepsis? We therefore propose this protocol to determine whether the changes in the intestinal flora in patients after cardiac surgery with CPB are related to sepsis. Methods and Analysis: This study is a prospective observational case-control study to analyze the variation in the intestinal microflora and metabolites in patients undergoing cardiac surgery with CPB and to observe the outcomes of patients with routine clinical interventions. The control group will include healthy people without intestinal illness. Feces and blood samples will be acquired 1 day before cardiac surgery and within 24-72 h after cardiac surgery, and will be used for genomics and metabolomics analyses. Demographic data describing age, sex, main diagnosis, and past medical history and data related to the CPB time and application of antibiotics are available. Sequential (sepsis-related) organ failure assessment, infection-related laboratory items, infection site, and pathogenic microorganisms, and nutrition, and gastrointestinal function assessment are additionally recorded. Group analysis of data will be conducted according to the outcomes (sepsis vs. non-sepsis and survivors vs. non-survivors). Ethics and Dissemination: This protocol has been ethically approved by the Ethics Committee of Peking Union Medical College (ID: ZS-1612). Informed consent will be obtained before subject enrolment, and data will be stored in a secured database. The results will be submitted to international peer-reviewed journals and presented at international conferences. Trial Registration Number: NCT04032938.

Impact of Fiber-Based Enteral Nutrition on the Gut Microbiome of ICU Patients Receiving Broad-Spectrum Antibiotics: A Randomized Pilot Trial

Supplemental Digital Content is available in the text.

Objectives:

Dietary fiber increases the abundance of bacteria that metabolize fiber into short-chain fatty acids and confers resistance against gut colonization with multidrug-resistant bacteria. This pilot trial estimated the effect of fiber on gut short-chain fatty acid–producing bacteria in the ICU.

Design:

Randomized, controlled, open label trial.

Setting:

Medical ICU.

Patients:

Twenty ICU adults receiving broad-spectrum IV antibiotics for sepsis.

Intervention:

1:1 randomization to enteral nutrition with mixed soy- and oat-derived fiber (14.3 g fiber/L) versus calorie- and micronutrient-identical enteral nutrition with 0 g/L fiber.

Measurements:

Rectal swabs and whole stools were collected at baseline and on study Days 3, 7, 14, and 30. The primary outcome was within-individual change in the cumulative relative abundance of short-chain fatty acid–producing taxa from baseline to Day 3 based on 16S sequencing of rectal swabs. The secondary outcome was Day 3 cumulative short-chain fatty acid levels based on mass spectrometry of whole stools. Analyses were all intent to treat.

Main Results:

By Day 3, the fiber group received a median of 32.1 g fiber cumulatively (interquartile range, 17.6–54.6) versus 0 g fiber (interquartile range, 0–4.0) in the no fiber group. The median within-individual change in short-chain fatty acid producer relative abundance from baseline to Day 3 was +61% (interquartile range −51 to +1,688) in the fiber group versus −46% (interquartile range, −78 to +13) in the no fiber group (p = 0.28). Whole stool short-chain fatty acid levels on Day 3 were a median of 707 μg short-chain fatty acids/g stool (interquartile range, 190–7,265) in the fiber group versus 118 μg short-chain fatty acids/g stool (interquartile range, 22–1,195) in the no fiber group (p = 0.16).

Conclusions:

Enteral fiber was associated with nonsignificant trends toward increased relative abundance of short-chain fatty acid–producing bacteria and increased short-chain fatty acid levels among ICU patients receiving broad-spectrum IV antibiotics. Larger studies should be undertaken and our results can be used for effect size estimates.

Stool Short-Chain Fatty Acids in Critically Ill Patients with Sepsis

Objective: To determine the concentration of stool short-chain fatty acids (SCFAs) in critically ill patients with sepsis and to compare the results between the critically ill patient and the control group.Methods: This descriptive, multicenter, observational study was conducted in five health institutions. Over a 6-month study period, critically ill patients with sepsis who were admitted to the intensive care unit (ICU) and met the inclusion criteria were enrolled, and a control, paired by age and sex, was recruited for each patient. A spontaneous stool sample was collected from each participant and a gas chromatograph coupled to a mass spectrometer (Agilent 7890/MSD 5975 C) was used to measure the concentrations SCFAs.Results: The final sample included 44 patients and 45 controls. There were no differences in the age and sex distributions between the groups (p > 0.05). According to body mass index (BMI), undernutrition was more prevalent among critically ill patients, and BMI in control subjects was most frequently classified as overweight (p = 0.024). Propionic acid, acetic acid, butyric acid, and isobutyric acid concentrations were significantly lower in the critically ill patient group than in the control group (p = 0.000). No association with outcome variables (complications, ICU stay, and discharge condition) was found in the patients, and patients diagnosed with infection on ICU admission showed significant decreases in butyric and isobutyric acid concentrations with respect to other diagnostic criteria (p < 0.05).Conclusions: The results confirm significantly lower concentrations of stool SCFAs in critically ill patients with sepsis than in control subjects. Due to its role in intestinal integrity, barrier function, and anti-inflammatory effect, maintaining the concentration of SCFAs may be important in the ICU care protocols of the critical patient.

Jerusalem Artichoke Powder Mixed in Enteral Feeding for Patients Who have Diarrhea in Surgical Intensive Care Unit: A Method of Preparation and a Pilot Study

Aim and objective

The Jerusalem artichoke (Helianthus tuberosus L.) is a tuber with high soluble fiber. The objective of this study was to demonstrate the method of preparation and pilot test this substance as an additive to enteral feeding.

Materials and methods

We processed Jerusalem artichoke into a 600 micrometers powder, tested its properties, and pilot tested its use in patients who had diarrhea (King's stool score ≥12) in a surgical intensive care unit. Two grams of Jerusalem artichoke powder were mixed in each 100 mL of hospital enteral feeding formula and administered for 5 days.

Results

Artichoke powder slightly increased the viscosity of enteral feeding formula. The dietary fiber content of the mixture was 20.8-21.6 g% and the content of fructans was 66.0-71.5 g%. In the pilot study in 11 patients, diarrhea was improved (diarrhea score < 12) in 7/11 (63.6%) patients by day 5. Improvement in diarrhea started on day 2 [median different diarrhea score (interquartile range): -4 (-8 to 0); p = 0.03] and peaked by days 4 and 5 [-7(-10 to -3); p < 0.01 and -8(-12 to -4); p < 0.01, respectively]. There were no complications during the study except three patients had a high gastric residual volume (>200 mL).

Conclusion

Processed powder of Jerusalem artichoke tuber has a high fiber content and increases viscosity of enteral feeding solutions only slightly. When administered as part of enteral nutrition to critically ill surgical patients, the diarrhea score improves in most patients.

How to cite this article

Chittawatanarat K, Surawang S, Simapaisan P, Judprasong K. Jerusalem Artichoke Powder Mixed in Enteral Feeding for Patients Who have Diarrhea in Surgical Intensive Care Unit: A Method of Preparation and a Pilot Study. Indian J Crit Care Med 2020;24(11):1051-1056.

The impact of dietary fiber and probiotics in infectious diseases

Although antibiotics are commonly used to treat infectious diseases, emergence of antibiotic resistant strains highlights the necessity for developing novel alternative approaches. Meanwhile, clinically, antibiotics can destroy the gut microbes balance, which is not conducive to the recovery of infectious disorders. As a result, recent studies have begun to explore potential prevention and treatment methods for infectious diseases, starting with more readily available dietary fiber and probiotics. Moreover, researches have shown the personalized nature of host responses to dietary fiber intervention, with outcomes being dependent on individual pre-treatment gut microbes. In this review, we will focus on the roles of dietary fiber and probiotics on infectious diseases, how probiotics and dietary fiber work on infectious diseases and then explore their mechanisms, so as to guide clinical consideration of new therapies for infectious diseases.

Impact of Soluble Fiber in the Microbiome and Outcomes in Critically Ill Patients

PURPOSE OF REVIEW

To discuss the controversy over the effect of dietary fiber (DF) on (1) outcomes in critical illness, (2) microbiome and metabolic homeostasis, and (3) current evidence and guidelines regarding supplementation in critically ill patients.

RECENT FINDINGS

In healthy individuals, consumption of DF is widely known as a long-term protecting factor against colon cancer, cardiovascular disease, and other metabolic disorders like obesity, type 2 diabetes, and fatty liver disease; in hospitalized patients, DF may have a beneficial effect in the incidence of diarrhea, infections, and length of stay. But, what does that mean for critically ill patients? What is the recommended DF intake and what are current guidelines? There are many confounding factors that limit the evidence of beneficial effects from fiber supplementation in critically ill patients, including the side effects critical care therapies can have on gut microbiota, but after extrapolating data from healthy and hospitalized non-critical patients and considering that its administration appears to be safe, it may be wise to administer fiber-containing enteral feedings in ICU patients. Analysis of those confounders requires future research.

Relationship Between Dietary Fiber Intake and Short-Chain Fatty Acid-Producing Bacteria During Critical Illness: A Prospective Cohort Study

BACKGROUND

Dietary fiber increases short-chain fatty acid (SCFA)-producing bacteria yet is often withheld in the intensive care unit (ICU). This study evaluated the safety and effect of fiber in ICU patients with gut microbiome sampling.

METHODS

This was a retrospective study nested within a prospective cohort. Adults were included if newly admitted to the ICU and could receive oral nutrition, enteral feedings, or no nutrition. Rectal swabs were performed at admission and 72 hours later. The primary exposure was fiber intake over 72 hours, classified in tertiles and adjusted for energy intake. The primary outcome was the relative abundance (RA) of SCFA producers via 16S RNA sequencing and the tolerability of fiber.

RESULTS

In 129 patients, median fiber intake was 13.4 g (interquartile range 0-35.4 g) over 72 hours. The high-fiber group had less abdominal distension (11% high fiber vs 28% no fiber, P < .01) and no increase in diarrhea (15% high fiber vs 13% no fiber, P = .94) or other adverse events. The median RA of SCFA producers after 72 hours was 0.40%, 0.50%, and 1.8% for the no-, low-, and high-fiber groups (P = .05 for trend). After correcting for energy intake, the median RA of SCFA producers was 0.41%, 0.32%, and 2.35% in the no-, low-, and high-corrected-fiber categories (P < .01). These associations remained significant after adjusting for clinical factors including antibiotics.

CONCLUSIONS

During the 72 hours after ICU admission, fiber was well tolerated, and higher fiber intake was associated with more SCFA-producers.

Prebiotic supplementation in frail older people affects specific gut microbiota taxa but not global diversity

BACKGROUND

There are complex interactions between aging, frailty, diet, and the gut microbiota; modulation of the gut microbiota by diet could lead to healthier aging. The purpose of this study was to test the effect of diets differing in sugar, fat, and fiber content upon the gut microbiota of mice humanized with microbiota from healthy or frail older people. We also performed a 6-month dietary fiber supplementation in three human cohorts representing three distinct life-stages.

METHODS

Mice were colonized with human microbiota and then underwent an 8-week dietary intervention with either a high-fiber/low-fat diet typical of elderly community dwellers or a low-fiber/high-fat diet typical of long-stay residential care subjects. A cross-over design was used where the diets were switched after 4 weeks to the other diet type to identify responsive taxa and innate immunity changes. In the human intervention, the subjects supplemented their normal diet with a mix of five prebiotics (wheat dextrin, resistant starch, polydextrose, soluble corn fiber, and galactooligo-saccharide) at 10 g/day combined total, for healthy subjects and 20 g/day for frail subjects, or placebo (10 g/day maltodextrin) for 26 weeks. The gut microbiota was profiled and immune responses were assayed by T cell markers in mice, and serum cytokines in humans.

RESULTS

Humanized mice maintained gut microbiota types reflecting the respective healthy or frail human donor. Changes in abundance of specific taxa occurred with the diet switch. In mice with the community type microbiota, the observed differences reflected compositions previously associated with higher frailty. The dominance of Prevotella present initially in community inoculated mice was replaced by Bacteroides, Alistipes, and Oscillibacter. Frail type microbiota showed a differential effect on innate immune markers in both conventional and germ-free mice, but a moderate number of taxonomic changes occurring upon diet switch with an increase in abundance of Parabacteroides, Blautia, Clostridium cluster IV, and Phascolarctobacterium. In the human intervention, prebiotic supplementation did not drive any global changes in alpha- or beta-diversity, but the abundance of certain bacterial taxa, particularly Ruminococcaceae (Clostridium cluster IV), Parabacteroides, Phascolarctobacterium, increased, and levels of the chemokine CXCL11 were significantly lower in the frail elderly group, but increased during the wash-out period.

CONCLUSIONS

Switching to a nutritionally poorer diet has a profound effect on the microbiota in mouse models, with changes in the gut microbiota from healthy donors reflecting previously observed differences between elderly frail and non-frail individuals. However, the frailty-associated gut microbiota did not reciprocally switch to a younger healthy-subject like state, and supplementation with prebiotics was associated with fewer detected effects in humans than diet adjustment in animal models.

Use of dietary fibers in enteral nutrition of critically ill patients: a systematic review

To meet the nutritional requirements of patients admitted to intensive care units, it is necessary to establish a diet schedule. Complications associated with enteral nutrition by tube feeding are not uncommon and may reduce the delivery of required nutrient to patients in intensive care units. Research on the osmolality, fat content, caloric intensity and fiber content of formulas are under way, and a substantial number of studies have focused on fiber content tolerability or symptom reduction. We conducted a systematic review of dietary fiber use and safety in critically ill patients in 8 studies based on diarrhea, other gastrointestinal symptoms (abdominal distension, gastric residual volume, vomiting and constipation), intestinal microbiota, length of stay in the intensive care unit and death. We discussed the results reported in the scientific literature and current recommendations. This contemporary approach demonstrated that the use of soluble fiber in all hemodynamically stable, critically ill patients is safe and should be considered beneficial for reducing the incidence of diarrhea in this population.

Rapid gastrointestinal loss of Clostridial Clusters IV and XIVa in the ICU associates with an expansion of gut pathogens

Commensal gastrointestinal bacteria resist the expansion of pathogens and are lost during critical illness, facilitating pathogen colonization and infection. We performed a prospective, ICU-based study to determine risk factors for loss of gut colonization resistance during the initial period of critical illness. Rectal swabs were taken from adult ICU patients within 4 hours of admission and 72 hours later, and analyzed using 16S rRNA gene sequencing and selective culture for vancomycin-resistant Enterococcus (VRE). Microbiome data was visualized using principal coordinate analyses (PCoA) and assessed using a linear discriminant analysis algorithm and logistic regression modeling. 93 ICU patients were analyzed. At 72 hours following ICU admission, there was a significant decrease in the proportion of Clostridial Clusters IV/XIVa, taxa that produce short chain fatty acids (SCFAs). At the same time, there was a significant expansion in Enterococcus. Decreases in Cluster IV/XIVa Clostridia were associated with loss of gut microbiome colonization resistance (reduced diversity and community stability over time). In multivariable analysis, both decreased Cluster IV/XIVa Clostridia and increased Enterococcus after 72 hours were associated with receipt of antibiotics. Cluster IV/XIVa Clostridia, although a small fraction of the overall gastrointestinal microbiome, drove distinct clustering on PCoA. During initial treatment for critical illness, there was a loss of Cluster IV/XIVa Clostridia within the distal gut microbiome which associated with an expansion of VRE and with a loss of gut microbiome colonization resistance. Receipt of broad-spectrum antibiotics was associated with these changes.

Implications of butyrate and its derivatives for gut health and animal production

Butyrate is produced by microbial fermentation in the large intestine of humans and animals. It serves as not only a primary nutrient that provides energy to colonocytes, but also a cellular mediator regulating multiple functions of gut cells and beyond, including gene expression, cell differentiation, gut tissue development, immune modulation, oxidative stress reduction, and diarrhea control. Although there are a large number of studies in human medicine using butyrate to treat intestinal disease, the importance of butyrate in maintaining gut health has also attracted significant research attention to its application for animal production, particularly as an alternative to in-feed antibiotics. Due to the difficulties of using butyrate in practice (i.e., offensive odor and absorption in the upper gut), different forms of butyrate, such as sodium butyrate and butyrate glycerides, have been developed and examined for their effects on gut health and growth performance across different species. Butyrate and its derivatives generally demonstrate positive effects on animal production, including enhancement of gut development, control of enteric pathogens, reduction of inflammation, improvement of growth performance (including carcass composition), and modulation of gut microbiota. These benefits are more evident in young animals, and variations in the results have been reported. The present article has critically reviewed recent findings in animal research on butyrate and its derivatives in regard to their effects and mechanisms behind and discussed the implications of these findings for improving animal gut health and production. In addition, significant findings of medical research in humans that are relevant to animal production have been cited.

The Need to Reassess Dietary Fiber Requirements in Healthy and Critically Ill Patients

This article provides evidence that current dietary fiber intake levels may be insufficient to maintain colonic mucosal health and defense, and reduce inflammation and cancer risk in otherwise healthy people. Current commercial tube feeds generally overlook the metabolic needs of the colon and may predispose patients to dysbiosis, bacterial overgrowth with pathogens such as Clostridium difficile, and acute colitis. These results raise concern about the wide-scale use of prophylactic antibiotics in the intensive care unit and the use of elemental, fiber-depleted tube feeds. Nutrition support is not complete without the addition of sufficient fiber to meet colonic nutritional needs.

Pancreatic and Intestinal Function Post Roux-en-Y Gastric Bypass Surgery for Obesity

OBJECTIVES

Despite the fact that the most effective treatment for morbid obesity today is gastric bypass surgery, some patients develop life-threatening nutritional complications associated with their weight loss.

METHODS

Here we examine the influence of the altered anatomy and digestive physiology on pancreatic secretion and fat absorption. Thirteen post Roux-en-Y gastric bypass (RYGB) patients who had lost >100 lbs in the first year following surgery and who gave variable histories of gastrointestinal (GI) dysfunction, were selected for study. Food-stimulated pancreatic enzyme secretion and GI hormone responses were measured during 2 h perfusions of the Roux limb with a standard polymeric liquid formula diet and polyethylene glycol marker, with collections of secretions from the common channel distal to the anastomosis and blood testing. Fat absorption was then measured during a 72 h balance study when a normal diet was given containing ~100 g fat/d.

RESULTS

Result showed that all patients had some fat malabsorption, but eight had coefficients of fat absorption <80%, indicative of steatorrhea. This was associated with significantly lower feed-stimulated secretion rates of trypsin, amylase, and lipase, and higher plasma peptide-YY concentrations compared with healthy controls. Five steatorrhea patients were subsequently treated with low quantities of pancreatic enzyme supplements for 3 months, and then retested. The supplements were well tolerated, and fat absorption improved in four of five patients accompanied by an increase in lipase secretion, but body weight increased in only three. Postprandial breath hydrogen concentrations were elevated with some improvement following enzyme supplementation suggesting persistent bacterial overgrowth and decreased colonic fermentation.

CONCLUSIONS

Our investigations revealed a wide spectrum of gastrointestinal abnormalities, including fat malabsorption, impaired food stimulated pancreatic secretion, ileal brake stimulation, and bacterial overgrowth, in patients following RYGB which could be attributed to the breakdown of the normally highly orchestrated digestive anatomy and physiology.

The role of the gut microbiota in sepsis

For decades, the gut was thought to play an important role in sepsis pathogenesis. Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Organ failure assessment for sepsis focuses on respiratory, cardiovascular, hepatic, renal, neurological, and haematological systems. Unfortunately, symptoms of gut failure are non-specific and are therefore not assessed. The composition of the intestinal microbiome, however, is affected by sepsis, and might contribute to the development of organ failure. Experimental work underscores the role of the microbiota in maintaining gut-barrier function, and modulation of the innate and adaptive immune system. Translation of these preclinical findings into functional characterisations will be essential to understand how disruption of commensals affects susceptibility and outcome of sepsis. In this Review, we identify knowledge gaps which, if addressed, will help researchers understand the role of the microbiota in sepsis, and provide microbiota-targeted tools to improve sepsis management.

Critically ill patients demonstrate large interpersonal variation in intestinal microbiota dysregulation: a pilot study

Purpose

The intestinal microbiota has emerged as a virtual organ with essential functions in human physiology. Antibiotic-induced disruption of the microbiota in critically ill patients may have a negative influence on key energy resources and immunity. We set out to characterize the fecal microbiota composition in critically ill patients both with and without sepsis and to explore the use of microbiota-derived markers for clinical outcome measurements in this setting.

Methods

In this prospective observational cohort study we analyzed the fecal microbiota of 34 patients admitted to the intensive care unit. Fifteen healthy subjects served as controls. The fecal microbiota was phylogenetically characterized by 16S rRNA gene sequencing, and associations with clinical outcome parameters were evaluated.

Results

A marked shift in fecal bacterial composition was seen in all septic and non-septic critically ill patients compared with controls, with extreme interindividual differences. In 13 of the 34 patients, a single bacterial genus made up >50% of the gut microbiota; in 4 patients this was even >75%. A significant decrease in bacterial diversity was observed in half of the patients. No associations were found between microbiota diversity, Firmicutes/Bacteroidetes ratio, or Gram-positive/Gram-negative ratio and outcome measurements such as complications and survival.

Conclusions

We observed highly heterogeneous patterns of intestinal microbiota in both septic and non-septic critically ill patients. Nevertheless, some general patterns were observed, including disappearance of bacterial genera with important functions in host metabolism. More detailed knowledge of the short- and long-term health consequences of these major shifts in intestinal bacterial communities is needed.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-016-4613-z) contains supplementary material, which is available to authorized users.

Microbiome as mediator: Do systemic infections start in the gut?

The intestinal microbiome is emerging as a crucial mediator between external insults and systemic infections. New research suggests that our intestinal microorganisms contribute to critical illness and the development of non-gastrointestinal infectious diseases. Common pathways include a loss of fecal intestinal bacterial diversity and a disproportionate increase in toxogenic bacterial species. Therapeutic interventions targeting the microbiome - primarily probiotics - have yielded limited results to date. However, knowledge in this area is rapidly expanding and microbiome-based therapy such as short-chain fatty acids may eventually become a standard strategy for preventing systemic infections in the context of critical illness.

Saccharomyces boulardii CNCM I-745 supports regeneration of the intestinal microbiota after diarrheic dysbiosis - a review

The probiotic medicinal yeast Saccharomyces cerevisiae HANSEN CBS 5926 (Saccharomyces boulardii CNCM I-745) is used for the prevention and treatment of diarrhea. Its action is based on multiple mechanisms, including immunological effects, pathogen-binding and antitoxinic effects, as well as effects on digestive enzymes. Correlated with these effects, but also due to its inherent properties, S. boulardii is able to create a favorable growth environment for the beneficial intestinal microbiota, while constituting extra protection to the host mucus layer and mucosa. This review focuses on the positive influence of S. boulardii on the composition of the intestinal microbiota. In a dysbiosis, as during diarrhea, the main microbial population (especially Lachnospiraceae, Ruminococcaceae, Bacteroidaceae, and Prevotellaceae) is known to collapse by at least one order of magnitude. This gap generally leads to transient increases in pioneer-type bacteria (Enterobacteriaceae, Bifidobacteriaceae, and Clostridiaceae). Several human studies as well as animal models demonstrate that treatment with S. boulardii in dysbiosis leads to the faster reestablishment of a healthy microbiome. The most relevant effects of S. boulardii on the fecal composition include an increase of short chain fatty acid-producing bacteria (along with a rise in short chain fatty acids), especially of Lachnospiraceae and Ruminococcaceae, as well as an increase in Bacteroidaceae and Prevotellaceae. At the same time, there is a suppression of pioneer bacteria. The previously observed preventive action of S. boulardii, eg, during antibiotic therapy or regarding traveler’s diarrhea, can be explained by several mechanisms, including a stabilizing effect on the healthy microbiota as well as possibly on the mucus layer. Several different dysbiotic situations could profit from the effects of S. boulardii CNCM I-745. Its additional potential lies in a general stabilization of the gut flora for at-risk populations. More studies are needed to explore the full potential of this versatile probiotic yeast.

Gut microbiota in older subjects: variation, health consequences and dietary intervention prospects

Alterations in intestinal microbiota composition and function have been linked to conditions including functional gastrointestinal disorders, obesity and diabetes. The gut microbiome encodes metabolic capability in excess of that encoded by the human genome, and bacterially produced enzymes are important for releasing nutrients from complex dietary ingredients. Previous culture-based studies had indicated that the gut microbiota of older people was different from that of younger adults, but the detailed findings were contradictory. Small-scale studies had also shown that the microbiota composition could be altered by dietary intervention or supplementation. We showed that the core microbiota and aggregate composition in 161 seniors was distinct from that of younger persons. To further investigate the reasons for this variation, we analysed the microbiota composition of 178 elderly subjects for whom the dietary intake data were available. The data revealed distinct microbiota composition groups, which overlapped with distinct dietary patterns that were governed by where people lived: at home, in rehabilitation or in long-term residential care. These diet-microbiota separations correlated with cluster analysis of NMR-derived faecal metabolites and shotgun metagenomic data. Major separations in the microbiota correlated with selected clinical measurements. It should thus be possible to programme the microbiota to enrich bacterial species and activities that promote healthier ageing. A number of other studies have investigated the effect of certain dietary components and their ability to modulate the microbiota composition to promote health. This review will discuss dietary interventions conducted thus far, especially those in elderly populations and highlight their impact on the intestinal microbiota.

Rapid and Sustained Long-Term Decrease of Fecal Short-Chain Fatty Acids in Critically Ill Patients With Systemic Inflammatory Response Syndrome

BACKGROUND

The gut is an important target organ for injury after severe insult. Short-chain fatty acids (SCFAs) are end-products of fermentation of dietary fibers by anaerobic microbiota. They are related to intestinal energy, motility, and transport and to protective effects against infection and inflammation. However, there are few clinical data on SCFAs in critically ill patients. We evaluated serial change in fecal SCFAs in patients with severe systemic inflammatory response syndrome (SIRS).

PATIENTS AND METHODS

This study included 140 intensive care unit (ICU) patients who fulfilled the criteria of SIRS and had a serum C-reactive protein level of >10 mg/dL. A fecal sample was used for quantitative measurement of fecal SCFA (butyrate, propionate, and acetate) concentrations by high-performance liquid chromatography. Fecal SCFAs were evaluated weekly for 6 weeks after admission. Data obtained from patients were compared with corresponding data from healthy volunteers.

RESULTS

SIRS resulted from infection in 78 patients, trauma in 30, burns in 12, and other causes in 20. Fecal concentrations of butyrate, propionate, and acetate in these patients decreased significantly compared with those in healthy volunteers and remained low throughout the 6 weeks of the patients' ICU stay. Fecal concentrations of SCFAs in the patients with gastrointestinal complications, including enteritis and dysmotility, were lower than those in the patients without gastrointestinal complications.

CONCLUSIONS

Concentrations of fecal SCFAs in patients with severe SIRS were significantly lower than those in healthy volunteers over a 6-week period. Maintenance of SCFAs may have therapeutic potential to prevent gastrointestinal complications in critically ill patients.

Effects of dietary nutrients on volatile breath metabolites

Breath analysis is becoming increasingly established as a means of assessing metabolic, biochemical and physiological function in health and disease. The methods available for these analyses exploit a variety of complex physicochemical principles, but are becoming more easily utilised in the clinical setting. Whilst some of the factors accounting for the biological variation in breath metabolite concentrations have been clarified, there has been relatively little work on the dietary factors that may influence them. In applying breath analysis to the clinical setting, it will be important to consider how these factors may affect the interpretation of endogenous breath composition. Diet may have complex effects on the generation of breath compounds. These effects may either be due to a direct impact on metabolism, or because they alter the gastrointestinal flora. Bacteria are a major source of compounds in breath, and their generation of H₂, hydrogen cyanide, aldehydes and alkanes may be an indicator of the health of their host.

Probiotic therapy as a novel approach for allergic disease

The prevalence of allergic disease has increased dramatically in Western countries over the past few decades. The hygiene hypothesis, whereby reduced exposure to microbial stimuli in early life programs the immune system toward a Th2-type allergic response, is suggested to be a major mechanism to explain this phenomenon in developed populations. Such microbial exposures are recognized to be critical regulators of intestinal microbiota development. Furthermore, intestinal microbiota has an important role in signaling to the developing mucosal immune system. Intestinal dysbiosis has been shown to precede the onset of clinical allergy, possibly through altered immune regulation. Existing treatments for allergic diseases such as eczema, asthma, and food allergy are limited and so the focus has been to identify alternative treatment or preventive strategies. Over the past 10 years, a number of clinical studies have investigated the potential of probiotic bacteria to ameliorate the pathological features of allergic disease. This novel approach has stemmed from numerous data reporting the pleiotropic effects of probiotics that include immunomodulation, restoration of intestinal dysbiosis as well as maintaining epithelial barrier integrity. In this mini-review, the emerging role of probiotics in the prevention and/or treatment of allergic disease are discussed with a focus on the evidence from animal and human studies.

Butyrate: implications for intestinal function

PURPOSE OF REVIEW

Butyrate is physiologically produced by the microbial fermentation of dietary fibers and plays a plurifunctional role in intestinal cells. This review examines the recent findings regarding the role and mechanisms by which butyrate regulates intestinal metabolism and discusses how these findings could improve the treatment of several gastrointestinal disorders.

RECENT FINDINGS

Butyrate is more than a primary nutrient that provides energy to colonocytes and acts as a cellular mediator in those cells through several mechanisms. One remarkable property of butyrate is its ability to inhibit histone deacetylases, which is associated with the direct effects of butyrate and results in gene regulation, immune modulation, cancer suppression, cell differentiation, intestinal barrier regulation, oxidative stress reduction, diarrhea control, visceral sensitivity and intestinal motility modulation. All of these actions make butyrate an important factor for the maintenance of gut health.

SUMMARY

From studies published over 30 years, there is no doubt of the important role that butyrate plays in maintaining intestinal homeostasis. However, despite these effects, clinical studies are still required to validate the routine use of butyrate in clinical practice and, specifically, in the treatment of intestinal diseases.

Enteral feeding patients with gastric outlet obstruction

Patients with upper gastrointestinal obstructions were previously managed with gastric decompression and parenteral feeding. The authors present their experience in 50 patients with obstructions chiefly due to complicated severe acute (n = 31) or chronic cystic pancreatitis (n = 11) using a double-lumen nasogastric decompression and jejunal feeding tube system (NGJ) held in place with a nasal bridle that passes through the obstructed gastroduodenal segments, allowing distal jejunal feeding, and at the same time decompresses the stomach to prevent vomiting and aspiration. The tip of the jejunal tube was placed approximately 40 cm down the jejunum to maintain pancreatic rest. Duration of feeding ranged from 1-145 days (median 25 days); 19 patients were discharged home with tube feeds. Only 1 patient could not tolerate feeding and needed to be converted to parenteral feeding. Average tube life was 14 days, with replacement being needed most commonly for kinking or clogging of the jejunal tube (56%) or accidental dislodgement (24%). The obstruction resolved spontaneously in 60%, allowing resumption of normal eating. Of the patients with severe acute pancreatitis or pancreatic pseudocysts, pancreatic rest resulted in resolution of the disease without surgery in 87%, and need for surgery in the remainder was put off for 31-76 days. Seven patients died predominantly of complications of acute pancreatitis between 1 and 31 days. In conclusion, NGJ feeding provides a relatively safe conservative management for critically ill patients with upper gastrointestinal obstructions, reducing the need for surgery and parenteral feeding.

Gut-central nervous system axis is a target for nutritional therapies

Historically, in the 1950s, the chemist Linus Pauling established a relationship between decreased longevity and obesity. At this time, with the advent of studies involving the mechanisms that modulate appetite control, some researchers observed that the hypothalamus is the "appetite centre" and that peripheral tissues have important roles in the modulation of gut inflammatory processes and levels of hormones that control food intake. Likewise, the advances of physiological and molecular mechanisms for patients with obesity, type 2 diabetes mellitus, inflammatory bowel diseases, bariatric surgery and anorexia-associated diseases has been greatly appreciated by nutritionists. Therefore, this review highlights the relationship between the gut-central nervous system axis and targets for nutritional therapies.