Gastrointestinal Dysfunction in Critical Illness: A Review of Scoring Tools

Prospective multicenter study to validate the gastrointestinal dysfunction score (GIDS) in intensive care patients: Study protocol for Part A of the international GUTPHOS study

BACKGROUND

While gastrointestinal (GI) dysfunction is commonly encountered among critically ill patients, a uniform prospectively validated scoring system is lacking. The present study aims to validate the recently developed Gastrointestinal Dysfunction Score (GIDS) in a multicenter, prospective cohort of consecutive adult patients admitted to intensive care units (ICU).

METHODS

GUTPHOS is a prospective, multicenter, non-interventional cohort study in which at least 1400 consecutive adult patients (age ≥18 years) admitted to the ICU will be monitored daily for abdominal signs and symptoms of GI dysfunction. The previously developed GIDS constructed from these signs and symptoms will be tested in relation to mortality and duration of ICU dependency and parenteral nutrition (PN) dependency. Between January and June 2024, each participating clinical site will include 50-120 consecutive patients over an eight-week period. Study data will be collected in three phases: baseline data upon ICU admission, daily observations throughout a maximum of 7 days in ICU or until discharge, and a follow-up period of 90 days. The primary outcomes are 28- and 90-day all-cause mortality. Secondary outcomes include ICU and hospital mortality, ICU and hospital length of stay, days alive and free of ICU by day 28 and day 90, days alive and free of hospital by day 28 and day 90, and days alive and free of organ support and PN dependency by day 28.

DISCUSSION

The GUTPHOS study will be the first worldwide, multicenter, prospective, observational cohort study to validate the GIDS in adult patients admitted to ICUs against 28- and 90-day mortality. The availability of a validated tool will allow its use in interventional studies that are currently hindered by the lack of a validated measurement tool for GI dysfunction.

CLINICAL TRIAL REGISTRY

NCT05909722.

Acute Gastrointestinal Injury in Critically Ill Patients in a South Indian Intensive Care Unit: A Prospective, Observational, Preliminary Study

Introduction The acute gastrointestinal injury (AGI) score was proposed by the Working Group on Abdominal Problems of the European Society of Intensive Care Medicine (ESICM) as a tool to define and grade gut dysfunction. There have not been any studies in India to validate this tool. The objective of this preliminary study was primarily to study the frequency of AGI in the first week of ICU stay in critically ill patients in our intensive care unit (ICU). We also sought to determine the risk factors predisposing to the development of AGI and to determine the prognostic implication of gastrointestinal (GI) injury in critically ill patients. Materials and methods A prospective, observational, preliminary, single-center study was conducted on critically ill patients (APACHE II > 8) who were on enteral tube feeds and admitted to a mixed ICU of a tertiary care hospital. Anthropometric data, admission diagnosis, APACHE II score, and comorbidities were recorded. Data of daily heart rate, mean arterial pressure, dose of vasopressors, intra-abdominal pressure, fluid balance, feeding intolerance, mechanical ventilation, and laboratory tests were noted for the first seven days of ICU stay or till ICU discharge, whichever was earlier. The occurrence of AGI score (1-4) during the first seven days of critical illness was the primary outcome of interest. Patient outcome at 28 days was recorded and the impact of the occurrence of AGI on patient outcome was analyzed using the Chi-square test. The patient characteristics associated with AGI were characterized as risk factors and analyzed using a multivariate model. Results Data were collected from 33 patients over 201 patient days. The frequency of acute GI dysfunction in the first seven days of ICU stay in our group of patients was 45.45% (15/33). APACHE II, fluid balance, creatinine, and lactate were identified as possible predictors of GI injury based on existing literature. These four variables were entered into an ordinal logistic regression model to assess their ability to predict the occurrence of GI Injury. When fitted into a predictive model, only fluid balance and creatinine were predictive of the final model (p-value < 0.05). A greater fluid balance was predictive in the final model of the development of GI injury; however, it showed negligible clinical significance (OR: 1.00033, 95% CI: 1.000051-1.00061). Lower creatinine levels were predictive in the final model of the development of AGI Injury, as demonstrated by the negative coefficient. Creatinine also had a greater clinical significance (OR: 0.63, 95% CI: 0.44-0.90) in the development of AGI. The impact of the AGI scores on mortality was analyzed. The number of patient days with higher AGI scores was significantly associated with increased mortality at 28 days (p-value < 0.001). Conclusion The study showed that nearly half of the critically ill patients included in the study developed acute GI dysfunction. We could not identify any predictors of GI injury based on our results. The result suggested an association between the severity of GI dysfunction and mortality at 28 days.

Ten good reasons to consider gastrointestinal function after acute brain injury

The brain-gut axis represents a bidirectional communication linking brain function with the gastrointestinal (GI) system. This interaction comprises a top-down communication from the brain to the gut, and a bottom-up communication from the gut to the brain, including neural, endocrine, immune, and humoral signaling. Acute brain injury (ABI) can lead to systemic complications including GI dysfunction. Techniques for monitoring GI function are currently few, neglected, and many under investigation. The use of ultrasound could provide a measure of gastric emptying, bowel peristalsis, bowel diameter, bowel wall thickness and tissue perfusion. Despite novel biomarkers represent a limitation in clinical practice, intra-abdominal pressure (IAP) is easy-to-use and measurable at bedside. Increased IAP can be both cause and consequence of GI dysfunction, and it can influence cerebral perfusion pressure and intracranial pressure via physiological mechanisms. Here, we address ten good reasons to consider GI function in patients with ABI, highlighting the importance of its assessment in neurocritical care.

Crosstalk Between the Nervous System and Systemic Organs in Acute Brain Injury

Organ crosstalk is a complex biological communication between distal organs mediated via cellular, soluble, and neurohormonal actions, based on a two-way pathway. The communication between the central nervous system and peripheral organs involves nerves, endocrine, and immunity systems as well as the emotional and cognitive centers of the brain. Particularly, acute brain injury is complicated by neuroinflammation and neurodegeneration causing multiorgan inflammation, microbial dysbiosis, gastrointestinal dysfunction and dysmotility, liver dysfunction, acute kidney injury, and cardiac dysfunction. Organ crosstalk has become increasingly popular, although the information is still limited. The present narrative review provides an update on the crosstalk between the nervous system and systemic organs after acute brain injury. Future research might help to target this pathophysiological process, preventing the progression toward multiorgan dysfunction in critically ill patients with brain injury.

Diarrhoea and constipation during artificial nutrition in intensive care unit: A prospective observational study

PURPOSE

To describe the occurrence of gastrointestinal (GI) complications, specifically diarrhoea and constipation, in artificially (enterally or parenterally) fed critically ill patients within their first seven-day stay in Intensive Care Unit (ICU).

METHODS

Observational prospective study conducted from September 1st to October 30th, 2019 and from August 1st to October 30th, 2021, in an ICU of a 1000-bed third-level hospital. General characteristics, nutritional variables, and medications administered were recorded and analysed. This study was registered on ClinicalTrials.gov (Identifier: NCT05473546).

RESULTS

In total, 100 critically ill patients were included. Diarrhoea was present in 44 patients (44.0%), while constipation occurred in 22 (22.0%) patients. Patients with diarrhoea were generally those admitted for respiratory failure, whereas patients without diarrhoea were mostly affected by neurological disorders (22.7% vs 25%, respectively; p = 0.002). Likewise, patients with constipation were primarily those admitted for trauma (36.4%). Trauma patients were almost 24 times more likely to be constipated than patients with respiratory failure (OR 23.99, CI 1.38-418.0) and patients receiving diuretics were over 16 times more likely to have diarrhoea than patients not receiving diuretics (OR 16.25, IC 1.89-139.86).

CONCLUSION

GI complications of enteral nutrition represent still a very common issue in ICU. The main predictor of constipation was an admission for trauma whereas the main predictor of diarrhoea was the use of diuretics. Clinicians should consider and integrate these findings into more personalized nutritional and management protocols to avoid gastrointestinal complications.

Gut barrier protein levels in serial blood samples from critically ill trauma patients during and after intensive care unit stay

PURPOSE

In an effort to better manage critically ill patients hospitalised in the intensive care unit (ICU) after experiencing multiple traumas, the present study aimed to assess whether plasma levels of intestinal epithelial cell barrier proteins, including occludin, claudin-1, junctional adhesion molecule (JAM-1), tricellulin and zonulin, could be used as novel biomarkers. Additional potential markers such as intestinal fatty acid-binding protein (I-FABP), D-lactate, lipopolysaccharide (LPS) and citrulline were also evaluated. We also aimed to determine the possible relationships between the clinical, laboratory, and nutritional status of patients and the measured marker levels.

METHODS

Plasma samples from 29 patients (first, second, fifth and tenth days in the ICU and on days 7, 30 and 60 after hospital discharge) and 23 controls were subjected to commercial enzyme-linked immunosorbent assay (ELISA) testing.

RESULTS

On first day (admission) and on the second day, plasma I-FABP, D-lactate, citrulline, occludin, claudin-1, tricellulin and zonulin levels were high in trauma patients and positively correlated with lactate, C-reactive protein (CRP), number of days of ICU hospitalisation, Acute Physiology and Chronic Health Evaluation II (APACHE II) score and daily Sequential Organ Failure Assessment (SOFA) scores (P < 0.05-P < 0.01).

CONCLUSION

The results of the present study showed that occludin, claudin-1, tricellulin and zonulin proteins, as well as I-FABP, D-lactate and citrulline, may be used as promising biomarkers for the evaluation of disease severity in critically ill trauma patients, despite the complexity of the analysis of various barrier markers. However, our results should be supported by future studies.

Factors associated with the need of parenteral nutrition in critically ill patients after the initiation of enteral nutrition therapy

Background and aims

Despite enteral nutrition (EN) is the preferred route of nutrition in patients with critical illness, EN is not always able to provide optimal nutrient provision and parenteral nutrition (PN) is needed. This is strongly associated with gastrointestinal (GI) complications, a feature of gastrointestinal dysfunction and disease severity. The aim of the present study was to investigate factors associated with the need of PN after start of EN, together with the use and complications associated with EN.

Methods

Adult patients admitted to 38 Spanish intensive care units (ICUs) between April and July 2018, who needed EN therapy were included in a prospective observational study. The characteristics of EN-treated patients and those who required PN after start EN were analyzed (i.e., clinical, laboratory and scores).

Results

Of a total of 443 patients, 43 (9.7%) received PN. One-third (29.3%) of patients presented GI complications, which were more frequent among those needing PN (26% vs. 60%, p = 0.001). No differences regarding mean energy and protein delivery were found between patients treated only with EN (n = 400) and those needing supplementary or total PN (n = 43). Abnormalities in lipid profile, blood proteins, and inflammatory markers, such as C-Reactive Protein, were shown in those patients needing PN. Sequential Organ Failure Assessment (SOFA) on ICU admission (Hazard ratio [HR]:1.161, 95% confidence interval [CI]:1.053-1.281, p = 0.003) and modified Nutrition Risk in Critically Ill (mNUTRIC) score (HR:1.311, 95% CI:1.098-1.565, p = 0.003) were higher among those who needed PN. In the multivariate analysis, higher SOFA score (HR:1.221, 95% CI:1.057-1.410, p = 0.007) and higher triglyceride levels on ICU admission (HR:1.004, 95% CI:1.001-1.007, p = 0.003) were associated with an increased risk for the need of PN, whereas higher albumin levels on ICU admission (HR:0.424, 95% CI:0.210-0.687, p = 0.016) was associated with lower need of PN.

Conclusion

A higher SOFA and nutrition-related laboratory parameters on ICU admission may be associated with the need of PN after starting EN therapy. This may be related with a higher occurrence of GI complications, a feature of GI dysfunction.

Clinical trial registration

ClinicalTrials.gov: NCT03634943.

Optimising the measurement of intra-bladder pressure in patients with predicted severe acute pancreatitis

BACKGROUND

Measuring intra-abdominal pressure (IAP) is important for management of patients with severe acute pancreatitis (SAP). Intra-bladder pressure (IBP) is an indirect index that reflects IAP, but measuring techniques vary. We sought to optimise IBP measuring techniques in predicted SAP patients.

METHODS

Predicted SAP patients consecutively admitted between June 2018 and January 2020 were scrutinised. Eligible patients had their IBP monitored for the first 72 h at 6-h intervals, and were then sequentially allocated into three research scenarios: (1) in the supine position along with head of bed elevation(HoBE)of 0, 15 and 30° at various points including the iliac crest the midaxillary line, pubic symphysis, and right atrium level, instilled with 25 mL normal saline (NS) at room temperature (RT); (2) NS instillation volume from 0, 10, 25, 40-50 mL at the iliac crest with HoBE15 at RT; and (3) NS instillation (25 mL) at either RT or 37 °C with HoBE15.

RESULTS

The dynamic IBP values measured at the pubic symphysis and iliac crest were fairly similar between HoBE0 and HoBE15 (all P > 0.05), but greatly increased at HoBE30 (all P < 0.01). IBP was significantly increased with escalating instillation volumes of NS (all P < 0.01 versus 0 mL NS), while there was no significant difference between 25 mL and 10 mL (P = 0.055). IBP was similar between NS at RT and under 37 °C (P = 0.643).

CONCLUSION

In predicted SAP patients, measuring IBP at the iliac crest with HoBE15 after instilling 10 mL of NS seems to be appropriate for monitoring IAP.

Effects of Different Routes and Forms of Vitamin D Administration on Mesenteric Lymph Node CD4+ T Cell Polarization and Intestinal Injury in Obese Mice Complicated with Polymicrobial Sepsis

This study compared the efficacies of enteral cholecalciferol and/or intravenous (IV) calcitriol administration on mesenteric lymph node (MLN) cluster-of-differentiation-4-positive (CD4+) T cell distribution and intestinal barrier damage in obese mice complicated with sepsis. Mice were fed a high-fat diet for 16 weeks and then sepsis was induced by cecal ligation and puncture (CLP). Mice were divided into the following sepsis groups: without vitamin D (VD) (S); with oral cholecalciferol 1 day before CLP (G); with IV calcitriol 1 h after CLP (V); and with both cholecalciferol before and IV calcitriol after CLP (GV). All mice were sacrificed at 12 or 24 h after CLP. The findings show that the S group had a higher T helper (Th)17 percentage than the VD-treated groups at 12 h after CLP. The V group exhibited a higher Th1 percentage and Th1/Th2 ratio than the other groups at 24 h, whereas the V and GV groups had a lower Th17/regulatory T (Treg) ratio 12 h post-CLP in MLNs. In ileum tissues, the VD-treated groups had higher tight junction protein and cathelicidin levels, and higher mucin gene expression than the S group at 24 h post-CLP. Also, aryl hydrocarbon receptor (AhR) and its associated cytochrome P450 1A1 and interleukin 22 gene expressions were upregulated. In contrast, levels of lipid peroxides and inflammatory mediators in ileum tissues were lower in the groups with VD treatment after CLP. These results suggest that IV calcitriol seemed to have a more-pronounced effect on modulating the homeostasis of Th/Treg subsets in MLNs. Both oral cholecalciferol before and IV calcitriol after CLP promoted cathelicidin secretion, alleviated intestinal inflammation, and ameliorated the epithelial integrity in obese mice complicated with sepsis possibly via VD receptor and AhR signaling pathways.

Association of Gastric Antrum Echodensity and Acute Gastrointestinal Injury in Critically Ill Patients

(1) Background: Acute muscle inflammation leads to increased sonographic echodensity. We developed a technique to characterize the echodensity of the gastric antrum wall and assess its feasibility in evaluating the severity of acute gastrointestinal injury (AGI); (2) Methods: The B-mode images of the gastric antrum of each enrolled patient were obtained daily by point-of-care ultrasound (POCUS). The 50th percentile, 85th percentile, and mean value of the grayscale distribution according to histogram analysis (ED50, ED85, and EDmean, respectively) were used to characterize the gastric antrum echodensity. Consistency and correlation analyses were performed to evaluate the feasibility and reproducibility of gastric antrum echodensity measurement. The association of gastric antrum echodensity with the severity of AGI and its ability to predict feeding intolerance (FI) were analyzed; (3) Results: In total, 206 POCUS images of 43 patients were analyzed. The gastric antrum echodensity measurements had sufficient intra- and inter-investigator reliabilities (intraclass correlation coefficient >0.9 for all parameters). The ED50 showed a significant upward trend as AGI severity increased, as well as ED85 and EDmean (p for trend <0.001, respectively). Patients who experienced FI had a higher ED50 (67.8 vs. 56.1, p = 0.02), ED85 (85.6 vs. 71.2, p = 0.01), and EDmean (70.3 vs. 57.6, p = 0.01) upon enteral feeding initiation; (4) Conclusions: Measurement of gastric antrum echodensity was technically feasible and reproducible in ventilated patients. Increased gastric antrum echodensity was associated with greater severity of AGI. Patients with higher gastric antrum echodensity upon enteral nutrition initiation via a nasogastric tube were more likely to develop FI.

Gastrointestinal Dysfunction Criteria in Critically Ill Children: The PODIUM Consensus Conference

CONTEXT

Prior criteria to define pediatric multiple organ dysfunction syndrome (MODS) did not include gastrointestinal dysfunction.

OBJECTIVES

Our objective was to evaluate current evidence and to develop consensus criteria for gastrointestinal dysfunction in critically ill children.

DATA SOURCES

Electronic searches of PubMed and EMBASE were conducted from January 1992 to January 2020, using medical subject heading terms and text words to define gastrointestinal dysfunction, pediatric critical illness, and outcomes.

STUDY SELECTION

Studies were included if they evaluated critically ill children with gastrointestinal dysfunction, performance characteristics of assessment/scoring tools to screen for gastrointestinal dysfunction, and assessed outcomes related to mortality, functional status, organ-specific outcomes, or other patient-centered outcomes. Studies of adults or premature infants, animal studies, reviews/commentaries, case series with sample size ≤10, and non-English language studies with inability to determine eligibility criteria were excluded.

DATA EXTRACTION

Data were abstracted from each eligible study into a standard data extraction form along with risk of bias assessment by a task force member.

RESULTS

The systematic review supports the following criteria for severe gastrointestinal dysfunction: 1a) bowel perforation, 1b) pneumatosis intestinalis, or 1c) bowel ischemia, present on plain abdominal radiograph, computed tomography (CT) scan, magnetic resonance imaging (MRI), or gross surgical inspection, or 2) rectal sloughing of gut mucosa.

LIMITATIONS

The validity of the consensus criteria for gastrointestinal dysfunction are limited by the quantity and quality of current evidence.

CONCLUSIONS

Understanding the role of gastrointestinal dysfunction in the pathophysiology and outcomes of MODS is important in pediatric critical illness.

The intensivist's assessment of gastrointestinal function: A pilot study

Gastrointestinal dysfunction/failure (GDF) is a common cause of concern in critically ill patients. Although the gut plays an important role in the genesis of organ failure, its exclusion from organ severity scoring systems has made it challenging for intensivists to score it sufficiently at the bedside. We aimed to survey intensive care specialists about their perceptions, attitudes, and approaches towards the assessment of the gut in Australia and New Zealand intensive care units (ICUs). An electronic (online) questionnaire was used to survey intensive care specialists from the Australia and New Zealand Intensive Care Society (ANZICS). The survey comprised 10 questions focused on four key areas: (i) the extent of the problem with GDF in ICUs, (ii) the use and reliability of the current gut scoring tools, (iii) personal approaches and practices associated with GDF assessment, and (4) potential value of a novel GDF scoring system and its incorporation into an organ severity score. Our results showed that GDF was a significant concern amongst ICUs in Australia and New Zealand intensivists (84%; 66/79), with a small number of participants (14%; 3/79) using a gut scoring tool in their ICUs. Despite this, we have no established objective scoring tool for its assessment. The survey highlighted the need for developing a novel scoring tool to assess the gut was considered important amongst majority of the intensivists (92%; 72/78), which would prove useful in clinical practice and potentially lead to incorporation into an organ severity score in the future.

Development of the Gastrointestinal Dysfunction Score (GIDS) for critically ill patients - A prospective multicenter observational study (iSOFA study)

BACKGROUND & AIMS

To develop a five grade score (0-4 points) for the assessment of gastrointestinal (GI) dysfunction in adult critically ill patients.

METHODS

This prospective multicenter observational study enrolled consecutive adult patients admitted to 11 intensive care units in nine countries. At all sites, daily clinical data with emphasis on GI clinical symptoms were collected and intra-abdominal pressure measured. In five out of 11 sites, the biomarkers citrulline and intestinal fatty acid-binding protein (I-FABP) were measured additionally. Cox models with time-dependent scores were used to analyze associations with 28- and 90-day mortality. The models were estimated with stratification for study center.

RESULTS

We included 540 patients (224 with biomarker measurements) with median age of 65 years (range 18-94), the Simplified Acute Physiology Score II score of 38 (interquartile range 26-53) points, and Sequential Organ Failure Assessment (SOFA) score of 6 (interquartile range 3-9) points at admission. Median ICU length of stay was 3 (interquartile range 1-6) days and 90-day mortality 18.9%. A new five grade Gastrointestinal Dysfunction Score (GIDS) was developed based on the rationale of the previously developed Acute GI Injury (AGI) grading. Citrulline and I-FABP did not prove their potential for scoring of GI dysfunction in critically ill. GIDS was independently associated with 28- and 90-day mortality when added to SOFA total score (HR 1.40; 95%CI 1.07-1.84 and HR 1.40; 95%CI 1.02-1.79, respectively) or to a model containing all SOFA subscores (HR 1.48; 95%CI 1.13-1.92 and HR 1.47; 95%CI 1.15-1.87, respectively), improving predictive power of SOFA score in all analyses.

CONCLUSIONS

The newly developed GIDS is additive to SOFA score in prediction of 28- and 90-day mortality. The clinical usefulness of this score should be validated prospectively.

TRIAL REGISTRATION

NCT02613000, retrospectively registered 24 November 2015.

Synbiotic Therapy Prevents Nosocomial Infection in Critically Ill Adult Patients: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials Based on a Bayesian Framework

Background: The efficacy of synbiotics, probiotics, prebiotics, enteral nutrition or adjuvant peripheral parenteral nutrition (EPN) and total parenteral nutrition (TPN) in preventing nosocomial infection (NI) in critically ill adults has been questioned. We conducted a systematic review and network meta-analysis (NMA) of randomized controlled trials (RCTs) to evaluate and rank the effectiveness of these therapies on NI amongst critically ill adults.

Methods: Four electronic databases were systematically searched up to June 30, 2019 for RCTs comparing the administration of probiotics, prebiotics, synbiotics, EPN and TPN in critically ill adults. The primary outcome was NI. The relative efficacy of all outcomes was determined by a Bayesian framework with random effects NMA. We estimated the odds ratio (OR) and mean difference (MD) and ranked the comparative effects of all regimens with the surface under the cumulative ranking probabilities. The study has been registered on PROSPERO (CRD42019147032).

Results: Fifty-five RCTs (7,119 patients) were identified. Primary outcome showed that synbiotics had the best effect in preventing NI than EPN (OR 0.37; 95% CrI 0.22–0.61), probiotics followed (OR 0.52; 95% CrI 0.34–0.77), whereas TPN significantly increased NI (OR 2.29; 95% CrI 1.48–3.67). Subgroup analysis showed that TPN significantly increased NI in intensive care unit (ICU) patients (OR 1.57; 95% CrI 1.01–2.56) and severe acute pancreatitis (SAP) patients (OR 3.93; 95% CrI 1.74–9.15). Secondary outcomes showed that synbiotics were more effective in preventing hospital-acquired pneumonia (HAP) (OR 0.34; 95% CrI 0.11–0.85), catheter-related bloodstream infection (OR 0.08; 95% CrI 0.01–0.80), urinary tract infection (OR 0.27; 95% CrI 0.08–0.71) and sepsis (OR 0.34; 95% CrI 0.16–0.70) than EPN. Amongst the treatments, probiotics were most effective for shortening the mechanical ventilation duration (MD −3.93; 95% CrI −7.98 to −0.02), prebiotics were most effective for preventing diarrhea (OR 0.24; 95% CrI 0.05–0.94) and TPN was the least effective in shortening hospital length of stay (MD 4.23; 95% CrI 0.97–7.33).

Conclusions: Amongst the five therapies, synbiotics not only prevented NI in critically ill adults but also demonstrated the best treatment results. By contrast, TPN did not prevent NI and ranked last, especially in ICU and SAP patients.

Take-Home Message: Nosocomial infection is a leading cause of mortality in critically ill patients in the ICU. However, the efficacy of synbiotics, probiotics, prebiotics, enteral nutrition or adjuvant peripheral parenteral nutrition and total parenteral nutrition in preventing nosocomial infection in critically ill adults has been questioned. The network meta-analysis provides evidence that amongst the five therapies, synbiotics not only prevented NI in critically ill adults but also demonstrated the best treatment results. By contrast, TPN did not prevent NI and ranked last, especially in ICU and SAP patients. The results of this study will provide a new scientific basis and a new idea for the debate on the efficacy of synbiotics and other treatments in the improvement of prognosis in critically ill adult patients.

Tweet: Synbiotic prevents nosocomial infection in critically ill adults, while total parenteral nutrition has the adverse curative.

Gut dysfunction in the ICU: diagnosis and management

PURPOSE OF REVIEW

Progress has been made in our understanding of gut dysfunction in critical illness. This review will outline new findings and give perspectives based on previous knowledge and concurrent advances in nutrition.

RECENT FINDINGS

The relationship between gut dysfunction and poor outcomes in critical illness has received considerable interest. It remains uncertain whether gut dysfunction is merely a marker of illness severity or if it is directly responsible for prolonged critical illness and increased mortality. This relationship is difficult to ascertain given there is no agreed method for identification and quantification; biomarkers such as intestinal fatty acid binding protein and citrulline show promise but require further study. Recent studies have investigated strategies to deliver enteral nutrition targets with impacts on gut function, including high calorie or protein formulae, intermittent regimes and novel prokinetics.

SUMMARY

Gut dysfunction is associated with poor outcomes, but it remains uncertain whether strategies to improve gut function will influence survival and recovery.

Prospective evaluation of a novel enteral feeding guideline based on individual gastric emptying times: an improvement project in a pediatric intensive care unit

BACKGROUND

On a 20-bed, mixed cardiac and general, UK pediatric intensive care unit (PICU), we aimed to determine if a physiologically based enteral feeding guideline for critically ill children, using feed frequency tailored to individual gastric emptying times, resulted in earlier establishment of full feeds (when 100% of fluid allowance (FA) available to be given as intravenous maintenance fluid or feed, defined as free FA [FFA], is given as enteral nutrition [EN]) and an increase in FFA given as EN.

METHODS

Four prospective audits (totaling 331 patients and 19,771 hours) were conducted at 1 year before guideline introduction and 1, 5, and 10 years after. Patient feeding data were collected from admission until day 4 or discharge, including reasons why feed was withheld.

RESULTS

The median time from admission to establishing full feeds decreased from 18 to 10 hours preguideline and postguideline and was sustained over 10 years. After adjustment for 5 confounders, this represented a reduction in the geometric mean time to full feeds of 30% (2009), 29% (2013), and 48% (2019) compared with 2007 (all P < .01). Nil-per-oral (NPO) hours were categorized as due to modifiable and nonmodifiable factors. Preguideline and postguideline NPO hours from modifiable factors decreased from 21 (2007) to 10 (2009) per 100 audit hours, which was sustained across 10 years (all P < .01). Conversely, NPO hours from nonmodifiable factors ranged from 27 to 36 per 100 audit hours throughout the audits, with no consistent trend over time. Similar inconsistency was shown in the proportion of FFA given as EN: 48% (2007), 71% (2009), 51% (2013), and 64% (2019). Continuous nasogastric and hourly bolus feeds decreased over time; they comprised 66% of feeds in 2007 but only 4%-11% in subsequent periods, being replaced with more 2-6 hour bolus, on-demand, or continuous nasojejunal feeds.

CONCLUSION

The guideline was associated with sustained reduction in the time to establishing full feeds and NPO hours due to modifiable factors and more or no less FFA being given as EN.

Gastrointestinal dysfunction in the critically ill: a systematic scoping review and research agenda proposed by the Section of Metabolism, Endocrinology and Nutrition of the European Society of Intensive Care Medicine

BACKGROUND

Gastrointestinal (GI) dysfunction is frequent in the critically ill but can be overlooked as a result of the lack of standardization of the diagnostic and therapeutic approaches. We aimed to develop a research agenda for GI dysfunction for future research. We systematically reviewed the current knowledge on a broad range of subtopics from a specific viewpoint of GI dysfunction, highlighting the remaining areas of uncertainty and suggesting future studies.

METHODS

This systematic scoping review and research agenda was conducted following successive steps: (1) identify clinically important subtopics within the field of GI function which warrant further research; (2) systematically review the literature for each subtopic using PubMed, CENTRAL and Cochrane Database of Systematic Reviews; (3) summarize evidence for each subtopic; (4) identify areas of uncertainty; (5) formulate and refine study proposals that address these subtopics; and (6) prioritize study proposals via sequential voting rounds.

RESULTS

Five major themes were identified: (1) monitoring, (2) associations between GI function and outcome, (3) GI function and nutrition, (4) management of GI dysfunction and (5) pathophysiological mechanisms. Searches on 17 subtopics were performed and evidence summarized. Several areas of uncertainty were identified, six of them needing consensus process. Study proposals ranked among the first ten included: prevention and management of diarrhoea; management of upper and lower feeding intolerance, including indications for post-pyloric feeding and opioid antagonists; acute gastrointestinal injury grading as a bedside tool; the role of intra-abdominal hypertension in the development and monitoring of GI dysfunction and in the development of non-occlusive mesenteric ischaemia; and the effect of proton pump inhibitors on the microbiome in critical illness.

CONCLUSIONS

Current evidence on GI dysfunction is scarce, partially due to the lack of precise definitions. The use of core sets of monitoring and outcomes are required to improve the consistency of future studies. We propose several areas for consensus process and outline future study projects.

Acute Intestinal Failure

Acute intestinal failure (AIF), "reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, requiring parenteral nutrition", is common, but very often neglected part of multiorgan dysfunction syndrome (MODS) in the critically ill patients. It is now increasingly being recognized as a cause of prolonged ICU and hospital stay and poor outcome. Multidisciplinary team approach, systematic approach to management with treatment of sepsis, early mobilization and enteral feeding with prokinetics if required, control of intra-abdominal pressure and surgical intervention, when mandated, can help treat AIF and improve patient outcomes. How to cite this article: Chandankhede SR, Kulkarni AP. Acute Intestinal Failure. Indian J Crit Care Med 2020;24(Suppl 4):S168-S174.