A systematic review of the definitions and prevalence of feeding intolerance in critically ill adults

Nurses' decision-making around gastric residual volume measurement in UK adult intensive care: A four-centre survey

BACKGROUND

Despite increasing evidence of the potential inaccuracy and unwarranted practice of regular GRV measurement in critically in adults, this practice persists within the United Kingdom.

AIM

To explore adult intensive care nurses' decision-making around the practice of GRV measurement to guide enteral feeding.

STUDY DESIGN

A cross-sectional 16 item electronic survey in four adult intensive care units (ICUs) in England and Wales.

RESULTS

Two hundred and seventy-three responses were obtained across four ICUs with acceptable response rates for most [Unit 1 74 /127 = 58.2%; Unit 2 87/129 = 67.4%; Unit 3 77/120 = 64.1%; Unit 4 35/168 = 20.8%]. Most (243/273 (89%) reported measuring GRV 4-6 hourly, with most (223/273 82%) reporting that the main reason was to assess feed tolerance or intolerance and 37/273 (13.5%) saying their unit protocol required it. In terms of factors affecting decision-making, volume obtained was the most important factor, followed by the condition of the patient, with aspirate colour and appearance less important. When asked how they would feel about not measuring GRV routinely, the majority (78.2%) of nurses felt worried (140/273 = 51.2%) or very worried (74/273 = 27%).

CONCLUSIONS

Factors affecting the nurses' decision-making around GRV were based largely on fear of risk (around vomiting and pulmonary aspiration) and compliance with unit protocols.

RELEVANCE TO CLINICAL PRACTICE

Despite increasing evidence suggesting it is unnecessary, nurses' beliefs around the value of this practice persist and it continues to be embedded into unit protocols around feeding.

An open-label, randomized controlled trial to assess a ketogenic diet in critically ill patients with sepsis

Patients with sepsis experience metabolic and immunologic dysfunction that may be amplified by standard carbohydrate-based nutrition. A ketogenic diet (KD) may offer an immunologically advantageous alternative, although clinical evidence is limited. We conducted a single-center, open-label, randomized controlled trial to assess whether a KD could induce stable ketosis in critically ill patients with sepsis. Secondary outcomes included assessment of feasibility and safety of KD, as well as explorative analysis of clinical and immunological characteristics. Forty critically ill adults were randomized to either a ketogenic or standard high-carbohydrate diet. Stable ketosis was achieved in all KD patients, with significant increases in β-hydroxybutyrate levels compared with controls [mean difference 1.4 milimoles per liter; 95% confidence interval (CI): 1.0 to 1.8; P < 0.001). No major adverse events or harmful metabolic side effects (acidosis, dysglycemia, or dyslipidemia) were observed. After day 4, none of the patients in the KD group required insulin treatment, whereas in the control group, insulin dependency ranged between 35% and 60% (P = 0.009). There were no differences in 30-day survival, but ventilation-free [incidence rate ratio (IRR) 1.7; 95% CI: 1.5 to 2.1; P < 0.001], vasopressor-free (IRR 1.7; 95% CI: 1.5 to 2.0; P < 0.001), dialysis-free (IRR 1.5; 95% CI: 1.3 to 1.8; P < 0.001), and intensive care unit-free days (IRR 1.7; 95% CI: 1.4 to 2.1; P < 0.001) were higher in the ketogenic group. Next-generation sequencing of CD4+/CD8+ T cells and protein analyses showed reduced immune dysregulation, with decreased gene expression of T-cell activation and signaling markers and lower pro-inflammatory cytokine secretion. This trial demonstrated the safe induction of a stable ketogenic state in sepsis, warranting larger trials to investigate potential benefits in sepsis-related organ dysfunction.

Investigating key factors of feeding intolerance in severe acute pancreatitis: A scoping review

BACKGROUND

The complexity of severe acute pancreatitis (SAP) and the stress caused by the disease is associated with a high incidence of feeding intolerance. However, the factors influencing feeding incontinence in patients with SAP are diverse.

AIMS

To systematically analyse relevant studies that investigate the occurrence of feeding intolerance in patients with SAP, identify the relevant factors of feeding intolerance in such patients and provide a reference for nursing staff to develop relevant intervention measures.

DESIGN AND METHODS

This scoping review followed the approach proposed by Arksey and O'Malley. Seven electronic databases were searched from their establishment until August 2023. This included research on the factors influencing feeding intolerance in patients with SAP, determining research questions, completing literature screening and quality evaluation, extracting data and summarizing and analysing the data. The PRISMA extension for scoping reviews (PRISMA-ScR) statement has also been included.

RESULTS

A total of 23 articles were included. The factors influencing feeding intolerance in patients with SAP included the patient's condition, disease, treatment, feeding management and follow-up care.

CONCLUSIONS

The factors affecting feeding intolerance in patients with SAP are multifaceted. A personalized nursing care plan should be developed based on relevant risk factors to improve feeding tolerance and comfort in patients with SAP and shorten hospitalization time.

RELEVANCE TO CLINICAL PRACTICE

Intensive care nurses should identify the risk factors for feeding intolerance in patients with SAP and implement appropriate interventions. To identify the risk factors, nurses must be updated with courses and training. Moreover, a systematic feeding intolerance prediction program can help intensive care nurses effectively identify the risk factors for feeding.

Dietitian's approach to managing enteral nutrition intolerance when a formula change is indicated: A clinical practice survey

BACKGROUND

Enteral nutrition intolerance (ENI) is often defined as one or more gastrointestinal (GI) symptoms related to enteral nutrition (EN) and may have significant impact on patient outcomes. There are multiple strategies to help manage ENI, such as changing the EN formula. The objective of this practice survey was to understand prevalence of ENI, management of ENI symptoms, and EN formula features considered when changing formulas to manage ENI.

METHODS

Canadian clinical dietitians working across care settings (n = 4827) were invited to complete a 28-question online survey if involved in the management of adult and/or pediatric patients receiving EN.

RESULTS

Five hundred seventeen surveys were analyzed. Significantly more dietitians in adult vs pediatric settings (83.4% and 59.1%, respectively; P = 0.0012), reported ENI in <40% of patients. Assessing medications, elevating the head of the bed, and changing EN infusion rate, volume, or feeding regimen were the highest-ranked strategies to manage ENI symptoms. Most (>90%) respondents change the EN formula <50% of the time to manage ENI. Dietitians consider caloric density and protein form as the most important EN features to manage upper-GI symptoms vs fiber source, osmolality, and form of protein to manage lower-GI symptoms. EN with real-food ingredients was ranked higher in importance for managing upper- and lower-GI symptoms by dietitians in pediatric vs adult settings.

CONCLUSION

To manage ENI symptoms, dietitians consider multiple strategies before deciding to change the EN formula. When a formula change is indicated, dietitians consider different EN features for the management of upper- and lower-GI symptoms.

Gastric residual volume monitoring practices in UK intensive care units: A web-based survey

Background and aim

Monitoring of gastric residual volume (GRV) to assess for enteral feeding intolerance is common practice in the intensive care unit (ICU) setting; however, evidence to support the practice is lacking. The aim of this study was: (i) to gain a perspective of current practice in adult ICUs in the UK around enteral feeding and monitoring of GRV, (ii) to characterise the threshold value used for a high GRV in clinical practice, (iii) to describe the impact of GRV monitoring on enteral feeding provision and (iv) to inform future research into the clinical value of GRV measurement in the adult ICU population.

Methods

A web-based survey was sent to all UK adult ICUs. The survey consisted of questions pertaining to (i) nutritional assessment and enteral feeding practices, (ii) enteral feeding intolerance and GRV monitoring and (iii) management of raised GRV.

Results

Responses were received from 101 units. Ninety-eight percent of units reported routinely measuring GRV, with 86% of ICUs using GRV to define enteral feeding intolerance. Threshold values for a high GRV varied from 200 to 1000 ml with frequency of measurement also differing greatly from 2 to 12 hourly. Initiation of pro-kinetic medication was the most common treatment for a high GRV. Fifty-two percent of respondents stated that volume of GRV would influence their decision to stop enteral feeds a lot or very much. Only 28% of units stated that they had guidelines for the technique for monitoring GRV.

Conclusions

Measurement of GRV is the most common method of determining enteral feeding intolerance in adult ICUs in the UK. The practice continues despite evidence of poor validity and reproducibility of this measurement. Further research should be undertaken into the benefit of ongoing GRV measurements in the adult ICU population and alternative markers of enteral feeding intolerance.

Clinical practice guidelines for nutritional assessment and monitoring of adult ICU patients in China

The Chinese Society of Critical Care Medicine (CSCCM) has developed clinical practice guidelines for nutrition assessment and monitoring for patients in adult intensive care units (ICUs) in China. This guideline focuses on nutrition evaluation and metabolic monitoring to achieve optimal and personalized nutrition therapy for critically ill patients. This guideline was developed by experts in critical care medicine and evidence-based medicine methodology and was developed after a thorough review of the system and a summary of relevant trials or studies published from 2000 to July 2023. A total of 18 recommendations were formed and consensus was reached through discussions and reviews by expert groups in critical care medicine, parenteral and enteral nutrition, and surgery. The recommendations are based on currently available evidence and cover several key fields, including screening and assessment, evaluation and assessment of enteral feeding intolerance, metabolic and nutritional measurement and monitoring during nutrition therapy, and organ function evaluation related to nutrition supply. Each question was analyzed according to the Population, Intervention, Comparison, and Outcome (PICO) principle. In addition, interpretations were provided for four questions that did not reach a consensus but may have potential clinical and research value. The plan is to update this nutrition assessment and monitoring guideline using the international guideline update method within 3-5 years.

Enteral nutrition in septic shock: a call for a paradigm shift

PURPOSE OF REVIEW

The purpose of this review is to identify contemporary evidence evaluating enteral nutrition in patients with septic shock, outline risk factors for enteral feeding intolerance (EFI), describe the conundrum of initiating enteral nutrition in patients with septic shock, appraise current EFI definitions, and identify bedside monitors for guiding enteral nutrition therapy.

RECENT FINDINGS

The NUTRIREA-2 and NUTRIREA-3 trial results have better informed the dose of enteral nutrition in critically ill patients with circulatory shock. In both trials, patients with predominant septic shock randomized to receive early standard-dose nutrition had more gastrointestinal complications. Compared to other contemporary RCTs that included patients with circulatory shock, patients in the NUTRIREA-2 and NUTRIREA-3 trials had higher bowel ischemia rates, were sicker, and received full-dose enteral nutrition while receiving high baseline dose of vasopressor. These findings suggest severity of illness, vasopressor dose, and enteral nutrition dose impact outcomes.

SUMMARY

The provision of early enteral nutrition preserves gut barrier functions; however, these benefits are counterbalanced by potential complications of introducing luminal nutrients into a hypo-perfused gut, including bowel ischemia. Findings from the NUTRIREA2 and NUTRIREA-3 trials substantiate a 'less is more' enteral nutrition dose strategy during the early acute phase of critical illness. In the absence of bedside tools to guide the initiation and advancement of enteral nutrition in patients with septic shock, the benefit of introducing enteral nutrition on preserving gut barrier function must be weighed against the risk of harm by considering dose of vasopressor, dose of enteral nutrition, and severity of illness.

Risk Factors of Enternal Nutrition Intolerance in Septic Patients: A Case-control Study

OBJECTIVE

This study aimed to investigate the incidence of enteral nutrition intolerance (ENI) in patients with sepsis and explore potential risk factors.

METHODS

A case-control study was conducted in patients with sepsis who were receiving enteral nutrition (EN) at a tertiary hospital in China. The included patients were divided into the ENI group and the non-ENI group. Univariate and multivariate analyses were performed to identify the risk factors for ENI.

RESULTS

A total of 859 patients were included in the study. Among them, 288 (33.53%) patients experienced symptoms of ENI, including diarrhea, vomiting, bloating, and gastric retention. Logistic regression analysis revealed that the Acute Physiology and Chronic Health Evaluation H (APACHE H) score, thoracocentesis, and usage of cardiotonic drugs (namely, inotropes) were independent predictors of the ENI.

CONCLUSION

The incidence of ENI is relatively high in patients with sepsis, especially in those who have higher APACHE H scores, have undergone thoracocentesis, and have received inotropes.

Controlled enteral nutrition in critical care patients - A randomized clinical trial of a novel management system

PURPOSE

Nutritional therapy is essential to ICU care. Successful early enteral feeding is hindered by lack of protocols, gastrointestinal intolerance and feeding interruptions, leading to impaired nutritional intake. smART+ was developed as a nutrition management feeding platform controlling tube positioning, reflux, gastric pressure, and malnutrition. This study evaluated the potential of this new ICU care platform to deliver targeted nutrition and improve ICU outcomes.

METHODS

Critically ill patients ≥18 years-old, mechanically ventilated and enterally fed, were randomized to receive ESPEN-guideline-based nutrition or smART+ -guided nutrition for 2-14 days. Primary endpoint was average deviation from daily targeted nutrition determined via calculation of energy targets per calorimetry. Secondary endpoints included gastric residual volumes, length of stay (LOS) and length of ventilation (LOV).

RESULTS

smART+ achieved a mean deviation from daily targeted nutrition of 10.5% (n = 48) versus 34.3% for control (n = 50), p < 0.0001. LOS and LOV were decreased in the smART+ group versus control (mean LOS: 10.4 days versus 13.7; reduction 3.3 days, adjusted HR 1.71, 95% CI:1.13,2.60, p = 0.012; mean LOV: 9.5 days versus 12.8 days reduction of 3.3 days, adjusted HR 1.64, 95% CI:1.08-2.51, p = 0.021). Feeding goals were met (within ±10%) on 75.7% of days for smART+ versus 23.3% for control (p < 0.001). No treatment-related adverse events occurred in either group. The study was stopped due to success in a planned interim analysis of the first 100 patients.

CONCLUSION

The smART+ Platform improved adherence to feeding goals and reduced LOS and LOV versus standard of care in critically ill patients.

TRIAL REGISTRATION

NCT04098224; registered September 23, 2019.

ESPEN practical and partially revised guideline: Clinical nutrition in the intensive care unit

Following the new ESPEN Standard Operating Procedures, the previous 2019 guideline to provide best medical nutritional therapy to critically ill patients has been shortened and partially revised. Following this update, we propose this publication as a practical guideline based on the published scientific guideline, but shortened and illustrated by flow charts. The main goal of this practical guideline is to increase understanding and allow the practitioner to implement the Nutrition in the ICU guidelines. All the items discussed in the previous guidelines are included as well as special conditions.

Different definitions of feeding intolerance and their associations with outcomes of critically ill adults receiving enteral nutrition: a systematic review and meta-analysis

BACKGROUND

A unified clinical definition of feeding intolerance (FI) is urged for better management of enteral nutrition (EN) in critically ill patients. We aimed to identify optimum clinical FI definitions based on reported evidence.

METHODS

We searched clinical studies comparing FI with non-FI with a clear definition, summarized the evidence by random-effect meta-analyses, and rated the certainty of evidence by the Grading of Recommendations Assessment, Development and Evaluation frameworks.

RESULTS

Five thousand five hundred twenty-five records were identified, of which 26 eligible studies enrolled 25,189 adult patients. Most patient-centered outcomes were associated with FI overall. Low to very low certainty evidence established FI defined as large gastric residual volume (GRV) ≥ 250 ± 50 mL combined with any other gastrointestinal symptoms (GIS) had a significant association with high mortalities in particular all-cause hospital mortality (odds ratio [OR] 1.90, 95% confidence interval [CI] 1.40-2.57), the incidence of pneumonia (OR 1.54, 95% CI 1.13-2.09) and prolonged length of hospital stay (mean difference 4.20, 95% CI 2.08-6.32), with a moderate hospital prevalence (41.49%, 95% CI 31.61-51.38%). 3-day enteral feeding (EF) delivered percentage < 80% had a moderate hospital prevalence (38.23%, 95% CI 24.88-51.58) but a marginally significant association with all-cause hospital mortality (OR 1.90, 95% CI 1.03-3.50).

CONCLUSIONS

In critically ill adult patients receiving EN, the large-GRV-centered GIS to define FI seemed to be superior to 3-day EF-insufficiency in terms of both close associations with all-cause hospital mortality and acceptable hospital prevalence (Registered PROSPERO: CRD42022326273).

TRIAL REGISTRATION

The protocol for this review and meta-analysis was registered with PROSPERO: CRD42022326273. Registered 10 May 2022.

Exploring the practice of nutritional support during hospitalization across physicians, dietitians, and pharmacists based in Saudi Arabia

Background

Nutritional support has a pivotal role in preventing and treating malnutrition. Recognizing the gaps in nutritional support practice can aid the development of tailored nutritional protocols. Therefore, this study aimed to assess the current practices, attitudes, and perceptions related to nutritional support for hospitalized patients in one of the largest Middle Eastern countries.

Methods

A cross-sectional study was conducted among different healthcare professionals currently working in hospitals in Saudi Arabia and involved in nutritional support practice. Data were collected using convenient sample via a self-administered web-based questionnaire.

Results

A total of 114 participants were included in this study. The majority were dietitians (54%), followed by physicians (33%) and pharmacists (12%), and were from the western region (71.9%). Various attitudes in many practices were observed among the participants. Only 44.7% of the participants had a formal nutritional support team. The mean confidence level of all respondents was significantly higher for enteral nutrition practice (7.7 ± 2.3) than for parenteral nutrition practice (6.1 ± 2.5) (p < 0.01). The confidence level for enteral nutrition practice was significantly influenced by nutritional qualification (β = 0.202, p < 0.05), type of healthcare facility (β = 0.210, p < 0.05), profession (β = -0.308, p < 0.01), and years of experience (β = 0.220, p < 0.05).

Conclusion

This study comprehensively assessed various aspects of nutritional support practice in Saudi Arabia. Healthcare practice of nutritional support should be guided by evidence-based guidelines. Professional qualification and training in nutritional support are essential for promoting practice in hospitals.

Current insights in ICU nutrition: tailored nutrition

PURPOSE OF REVIEW

To summarize recent research on critical care nutrition focusing on the optimal composition, timing, and monitoring of enteral feeding strategies for (post)-ICU patients. We provide new insights on energy and protein recommendations, feeding intolerance, and describe nutritional practices for coronavirus disease 2019 ICU patients.

RECENT FINDINGS

The use of indirect calorimetry to establish individual energy requirements for ICU patients is considered the gold standard. The limited research on optimal feeding targets in the early phase of critical illness suggests avoiding overfeeding. Protein provision based upon the absolute lean body mass is rational. Therefore, body composition measurements should be considered. Body impedance analysis and muscle ultrasound seem reliable, affordable, and accessible methods to assess body composition at the bedside. There is inadequate evidence to change our practice of continuous enteral feeding into intermittent feeding. Finally, severe acute respiratory syndrome coronavirus 2 patients are prone to underfeeding due to hypermetabolism and should be closely monitored.

SUMMARY

Nutritional therapy should be adapted to the patient's characteristics, diagnosis, and state of metabolism during ICU stay and convalescence. A personalized nutrition plan may prevent harmful over- or underfeeding and attenuate muscle loss. Despite novel insights, more research is warranted into tailored nutrition strategies during critical illness and convalescence.

Role of gastric ultrasound to guide enteral nutrition in the critically ill

PURPOSE OF REVIEW

Early initiation of enteral nutrition (EN) is often not feasible due to the high prevalence of gastrointestinal dysfunction that constitutes one of the leading nonavoidable causes for discontinuing or delaying enteral feeding in critically ill. This review summarizes current evidence on the role of gastric ultrasound as a management and monitoring tool for enteral nutrition in critically ill patients.

RECENT FINDINGS

The ultrasound meal accommodation test, the gastrointestinal and urinary track sonography (GUTS), and other gastric ultrasound protocols used to diagnose and treat gastrointestinal dysfunction in critically ill patients have not changed the outcome. However, this intervention could help clinicians with accurate daily clinical decisions. The dynamic changes in the cross-sectional area (CSA) diameter could help to access gastrointestinal dynamics results immediately, provide a valuable guide to initiate EN, predict feeding intolerance (FI), and aid in following treatment response. More studies are necessary to determine the complete scope and true added clinical value of these tests in critically ill patients.

SUMMARY

Using gastric point of care ultrasound (POCUS) is a noninvasive, radiation-free, and inexpensive method. Implementing the ultrasound meal accommodation test in ICU patients might become a step forward to ensure safe early enteral nutrition in critically ill patients.