Observed differences in nutrition management at two time points spanning a decade in critically ill trauma patients with and without head injury

BACKGROUND

Nutritional needs of trauma patients admitted to the intensive care unit may differ from general critically ill patients, but most current evidence is based on large clinical trials recruiting mixed populations.

OBJECTIVE

The aim of the study was to investigate nutrition practices at two time points that span a decade in trauma patients with and without head injury.

METHODS

This observational study recruited adult trauma patients receiving mechanical ventilation and artificial nutrition from a single-centre intensive care unit between February 2005 to December 2006 (cohort 1), and December 2018 to September 2020 (cohort 2). Patients were categorised into head injury and non-head injury subgroups. Data regarding energy and protein prescription and delivery were collected. Data are presented as median [interquartile range]. Wilcoxon rank-sum test assessed the differences between cohorts and subgroups, with a P value ≤ 0.05. The protocol was registered with the Australian and New Zealand Clinical Trials Registry (Trial ID: ACTRN12618001816246).

RESULTS

Cohort 1 included 109 patients, and 112 patients were included in cohort 2 (age: 46 ± 19 vs 50 ± 19 y; 80 vs 79% M). Overall, nutrition practice did not differ between head-injured and non-head-injured subgroups (all P > 0.05). Energy prescription and delivery decreased from time point one to time point two, regardless of subgroup (Prescription: 9824 [8820-10 581] vs 8318 [7694-9071] kJ; Delivery: 6138 [5130-7188] vs 4715 [3059-5996] kJ; all P < 0.05). Protein prescription did not change from time point one to time point two. Although protein delivery remained constant from time point one to time point two in the head injury group, protein delivery reduced in the non-head injury subgroup (70 [56-82] vs 45 [26-64] g/d, P < 0.05).

CONCLUSION

In this single-centre study, energy prescription and delivery in critically ill trauma patients reduced from time point one to time point two. Protein prescription did not change, but protein delivery reduced from time point one to time point two in non-head injury patients. Reasons for these differing trajectories require exploration.

STUDY REGISTRATION

Trial registered at www.anzctr.org.au.

TRIAL ID

ACTRN12618001816246.

Nutrition delivery across hospitalisation in critically ill patients with COVID-19: An observational study of the Australian experience

BACKGROUND

Data on nutrition delivery over the whole hospital admission in critically ill patients with COVID-19 are scarce, particularly in the Australian setting.

OBJECTIVES

The objective of this study was to describe nutrition delivery in critically ill patients admitted to Australian intensive care units (ICUs) with coronavirus disease 2019 (COVID-19), with a focus on post-ICU nutrition practices.

METHODS

A multicentre observational study conducted at nine sites included adult patients with a positive COVID-19 diagnosis admitted to the ICU for >24 h and discharged to an acute ward over a 12-month recruitment period from 1 March 2020. Data were extracted on baseline characteristics and clinical outcomes. Nutrition practice data from the ICU and weekly in the post-ICU ward (up to week four) included route of feeding, presence of nutrition-impacting symptoms, and nutrition support received.

RESULTS

A total of 103 patients were included (71% male, age: 58 ± 14 years, body mass index: 30±7 kg/m2), of whom 41.7% (n = 43) received mechanical ventilation within 14 days of ICU admission. While oral nutrition was received by more patients at any time point in the ICU (n = 93, 91.2% of patients) than enteral nutrition (EN) (n = 43, 42.2%) or parenteral nutrition (PN) (n = 2, 2.0%), EN was delivered for a greater duration of time (69.6% feeding days) than oral and PN (29.7% and 0.7%, respectively). More patients received oral intake than the other modes in the post-ICU ward (n = 95, 95.0%), and 40.0% (n = 38/95) of patients were receiving oral nutrition supplements. In the week after ICU discharge, 51.0% of patients (n = 51) had at least one nutrition-impacting symptom, most commonly a reduced appetite (n = 25; 24.5%) or dysphagia (n = 16; 15.7%).

CONCLUSION

Critically ill patients during the COVID-19 pandemic in Australia were more likely to receive oral nutrition than artificial nutrition support at any time point both in the ICU and in the post-ICU ward, whereas EN was provided for a greater duration when it was prescribed. Nutrition-impacting symptoms were common.

Comparison of energy intake in critical illness survivors, general medical patients, and healthy volunteers: A descriptive cohort study

BACKGROUND

Intensive care unit (ICU) survivors have reduced oral intake; it is unknown whether intake and associated barriers are unique to this group.

OBJECTIVE

To quantify energy intake and potential barriers in ICU survivors compared with general medical (GM) patients and healthy volunteers.

DESIGN

A descriptive cohort study in ICU survivors, GM patients, and healthy volunteers. Following an overnight fast, participants consumed a 200 ml test-meal (213 kcal) and 180 min later an ad libitum meal to measure energy intake (primary outcome). Secondary outcomes; taste recognition, nutrition-impacting symptoms, malnutrition, and quality of life (QoL). Data are mean ± SD, median (interquartile range [IQR]) or number [percentage]).

RESULTS

Twelve ICU survivors (57 ± 17 years, BMI: 30 ± 6), eight GM patients (69 ± 19 years, BMI: 30 ± 6), and 25 healthy volunteers (58 ± 27 years, BMI: 25 ± 4) were included. Recruitment ceased early because of slow recruitment and SARS-CoV-2. Energy intake was lower in both patient groups than in health (ICU: 289 [288, 809], GM: 426 [336, 592], health: 815 [654, 1165] kcal). Loss of appetite was most common (ICU: 78%, GM: 67%). For ICU survivors, GM patients and healthy volunteers, respectively, severe malnutrition prevalence; 40%, 14%, and 0%; taste identification; 8.5 [7.0, 11.0], 8.5 [7.0, 9.5], and 8.0 [6.0, 11.0]; and QoL; 60 [40-65], 50 [31-55], and 90 [81-95] out of 100.

CONCLUSIONS

Energy intake at a buffet meal is lower in hospital patients than in healthy volunteers but similar between ICU survivors and GM patients. Appetite loss potentially contributes to reduced energy intake.

Nutrition practices in hospitalized adults receiving noninvasive forms of respiratory support: A scoping review

The use of noninvasive respiratory support is increasing, with noninvasive ventilation (NIV) and high-flow nasal cannula providing unique barriers to nutrition support. Limited data related to nutrition management for these patients in the intensive care unit (ICU) exist; however, the literature in non-critically ill patients is not well described, and its improvement may help to inform practice within the ICU. Therefore, a scoping review was conducted of MEDLINE, EmCare, and Cumulative Index of Nursing and Allied Health Literature (CINAHL) databases on August 18, 2022, to identify original publications that included adult patients receiving noninvasive respiratory support in a hospital setting with data related to nutrition management. Data were extracted on study design, population, details of respiratory support, and concepts relating to nutrition management (grouped into nutrition screening, assessment, delivery route, intake, and anthropometry). Eleven studies were included, most of which were small (<100 patients), single-center, observational trials in patients receiving NIV only. Five studies reported results related to route of nutrition and nutrition assessment, two on anthropometry, and one each on quantifying intake and nutrition screening; some studies reported multiple parameters. There was a lack of consensus regarding the ideal method for nutrition assessment and route of nutrition. Oral nutrition was the route most frequently reported, yet calorie and protein delivery via this route were inadequate, and barriers to intake included poor appetite, fatigue, and patient cognition. Future research should address barriers pertinent to this population and the impact of nutrition on outcomes.

Nutrition practices in critically ill adults receiving noninvasive ventilation: A quantitative survey of Australian and New Zealand intensive care clinicians

BACKGROUND

Noninvasive ventilation (NIV) is frequently used in the intensive care unit (ICU), yet there is a paucity of evidence to guide nutrition management during this therapy. Understanding clinicians' views on nutrition practices during NIV will inform research to address this knowledge gap.

OBJECTIVE

The objective of this study was to describe Australian and New Zealand clinicians' views and perceptions of nutrition management during NIV in critically ill adults.

METHODS

A cross-sectional quantitative online survey of Australian and New Zealand medical and nursing staff with ≥12 months ICU experience was disseminated through professional organisations via purposive snowball sampling from 29 August to 9 October 2022. Data collection included demographics, current practices, and views and perceptions of nutrition during NIV. Surveys <50% complete were excluded. Data are represented in number (%).

RESULTS

A total of 152 surveys were analysed; 71 (47%) nursing, 69 (45%) medical, and 12 (8%) not specified. There was limited consensus on nutrition management during NIV; however, most clinicians (n = 108, 79%) reported that nutrition during NIV was 'important or very important'. Oral intake was perceived to be the most common route (n = 83, 55%), and 29 (21%) respondents viewed this as the safest. Most respondents (n = 106, 78%) reported that ≤50% of energy targets were met, with gastric enteral nutrition considered most likely to meet targets (n = 55, 40%). Reported nutrition barriers were aspiration risk (n = 87, 64%), fasting for intubation (n = 84, 62%), and nutrition perceived as a lower priority (n = 73, 54%). Reported facilitators were evidence-based guidelines (n = 77, 57%) and an NIV interface compatible with enteral nutrition tube (n = 77, 57%).

CONCLUSION

ICU medical and nursing staff reported nutrition during NIV to be important; however, there was a lack of consensus on the route of feeding considered to be the safest and most likely to achieve nutrition targets. Interventions to minimise aspiration and fasting, including an interface with nasoenteric tube compatibility, should be explored.

Dietary assessment methods for measurement of oral intake in acute care and critically ill hospitalised patients: a scoping review

Quantification of oral intake within the hospital setting is required to guide nutrition care. Multiple dietary assessment methods are available, yet details regarding their application in the acute care setting are scarce. This scoping review, conducted in accordance with JBI methodology, describes dietary assessment methods used to measure oral intake in acute and critical care hospital patients. The search was run across four databases to identify primary research conducted in adult acute or critical care settings from 1st of January 2000-15th March 2023 which quantified oral diet with any dietary assessment method. In total, 155 articles were included, predominantly from the acute care setting (n = 153, 99%). Studies were mainly single-centre (n = 138, 88%) and of observational design (n = 135, 87%). Estimated plate waste (n = 59, 38%) and food records (n = 43, 28%) were the most frequent assessment methods with energy and protein the main nutrients quantified (n = 81, 52%). Validation was completed in 23 (15%) studies, with the majority of these using a reference method reliant on estimation (n = 17, 74%). A quarter of studies (n = 39) quantified completion (either as complete versus incomplete or degree of completeness) and four studies (2.5%) explored factors influencing completion. Findings indicate a lack of high-quality evidence to guide selection and application of existing dietary assessment methods to quantify oral intake with a particular absence of evidence in the critical care setting. Further validation of existing tools and identification of factors influencing completion is needed to guide the optimal approach to quantification of oral intake in both research and clinical contexts.

Nutrition care processes across hospitalisation in critically ill patients with COVID-19 in Australia: A multicentre prospective observational study

BACKGROUND

The COVID-19 pandemic highlighted major challenges with usual nutrition care processes, leading to reports of malnutrition and nutrition-related issues in these patients.

OBJECTIVE

The objective of this study was to describe nutrition-related service delivery practices across hospitalisation in critically ill patients with COVID-19 admitted to Australian intensive care units (ICUs) in the initial pandemic phase.

METHODS

This was a multicentre (nine site) observational study in Australia, linked with a national registry of critically ill patients with COVID-19. Adult patients with COVID-19 who were discharged to an acute ward following ICU admission were included over a 12-month period. Data are presented as n (%), median (interquartile range [IQR]), and odds ratio (OR [95% confidence interval {CI}]).

RESULTS

A total of 103 patients were included. Oral nutrition was the most common mode of nutrition (93 [93%]). In the ICU, there were 53 (52%) patients seen by a dietitian (median 4 [2-8] occasions) and malnutrition screening occurred in 51 (50%) patients most commonly with the malnutrition screening tool (50 [98%]). The odds of receiving a higher malnutrition screening tool score increased by 36% for every screening in the ICU (1st to 4th, OR: 1.39 [95% CI: 1.05-1.77] p = 0.018) (indicating increasing risk of malnutrition). On the ward, 51 (50.5%) patients were seen by a dietitian (median time to consult: 44 [22.5-75] hours post ICU discharge). The odds of dietetic consult increased by 39% every week while on the ward (OR: 1.39 [1.03-1.89], p = 0.034). Patients who received mechanical ventilation (MV) were more likely to receive dietetic input than those who never received MV.

CONCLUSIONS

During the initial phases of the COVID-19 pandemic in Australia, approximately half of the patients included were seen by a dietitian. An increased number of malnutrition screens were associated with a higher risk score in the ICU and likelihood of dietetic consult increased if patients received MV and as length of ward stay increased.

Attenuating Muscle Mass Loss in Critical Illness: the Role of Nutrition and Exercise

PURPOSE OF REVIEW

Impaired recovery following an intensive care unit (ICU) admission is thought related to muscle wasting. Nutrition and physical activity are considered potential avenues to attenuate muscle wasting. The aim of this review was to present evidence for these interventions in attenuating muscle loss or improving strength and function.

RECENT FINDINGS

Randomised controlled trials on the impact of nutrition or physical activity interventions in critically ill adult patients on muscle mass, strength or function are presented. No nutrition intervention has shown an effect on strength or function, and the effect on muscle mass is conflicting. RCTs on the effect of physical activity demonstrate conflicting results; yet, there is a signal for improved strength and function with higher levels of physical activity, particularly when commenced early. Further research is needed to elucidate the impact of nutrition and physical activity on muscle mass, strength and function, particularly in combination.

Nutrition management of critically ill adult patients requiring non-invasive ventilation: a scoping review protocol

OBJECTIVE

This scoping review will identify the current available literature and key concepts in the nutrition management of critically ill adult patients requiring non-invasive ventilation.

INTRODUCTION

Current international nutrition guidelines include recommendations for the nutrition management of critically ill patients who are receiving invasive mechanical ventilation; however, these guidelines do not address nutrition management of patients receiving non-invasive ventilation. This scoping review aims to explore and describe the existing available literature on the nutrition management of critically ill adults requiring non-invasive ventilation.

INCLUSION CRITERIA

This review will consider original research (qualitative, quantitative, or mixed methods studies) reporting on any nutrition parameter for critically ill adult patients (≥16 years) requiring non-invasive ventilation in the intensive care unit. Concepts of interest based on the general intensive care nutrition literature include route of nutrition, recommendations related to macro- or micro-nutrients, nutrition provision, barriers to nutrition provision, and strategies for nutrition management.

METHODS

This review will be conducted in accordance with JBI methodology for scoping reviews using a three-step search strategy. MEDLINE, Embase, Scopus, and Web of Science will be searched to obtain original research available in English and published after 1990. Google Scholar will be searched for gray literature. Duplicates will be removed and studies will be selected by two independent reviewers based on the inclusion criteria. The same two reviewers will extract data in duplicate using a data extraction tool. Any disagreements will be resolved via consensus with a third reviewer. Data extraction will be synthesized in tabular and diagrammatic format.

Muscle Protein Synthesis Following Protein Administration in Critical Illness

Rationale Dietary protein may attenuate the muscle atrophy experienced by patients in the Intensive Care Unit (ICU), yet protein handling is poorly understood. Objective To quantify protein digestion and amino acid absorption, and fasting and postprandial myofibrillar protein synthesis during critical illness. Methods Fifteen mechanically ventilated adults (12M; age 50±17y, Body Mass Index (BMI) 27±5kg·m-2) and 10 healthy controls (6M; 54±23y, BMI 27±4kg·m-2) received a primed intravenous L-[ring-2H5]-phenylalanine, L-[3,5-2H2]-tyrosine, and L-[1-13C]-leucine infusion over 9.5h, and a duodenal bolus of intrinsically-labelled (L-[1-13C]-phenylalanine and L-[1-13C]-leucine) intact milk protein (20g protein) over 60min. Arterial blood and muscle samples were taken at baseline (fasting) and for 6h following duodenal protein administration. Data are mean±SD; analysed with 2-way repeated measures ANOVA and independent samples t-test. Measurements and main results Fasting myofibrillar protein synthesis rates did not differ between ICU patients and healthy controls (0.023±0.013 vs 0.034±0.016%/h; P=0.077). Following protein administration, plasma amino acid availability did not differ between groups (ICU patients 54.2±9.1 vs healthy controls 61.8±13.1%; P=0.12), and myofibrillar protein synthesis rates increased in both groups (0.028±0.010 vs 0.043±0.018 %/h, main time effect P=0.046, P-interaction=0.584) with lower rates in ICU patients compared to healthy controls (main group effect P=0.001). Incorporation of protein-derived phenylalanine into myofibrillar protein was ~60% lower in ICU patients (0.007±0.007 vs 0.017±0.009 mole % excess (MPE); P=0.007). Conclusion The capacity for critically ill patients to use ingested protein for muscle protein synthesis is markedly blunted despite relatively normal protein digestion and amino acid absorption.

Protocol summary and statistical analysis plan for ntensive utrition herapy compard to usual care i criically ill adults (INTENT): a phase II randomised controlled trial

INTRODUCTION

It is plausible that a longer duration of nutrition intervention may have a greater impact on clinical and patient-centred outcomes. The Intensive Nutrition care Therapy comparEd to usual care iN criTically ill adults (INTENT) trial will determine if a whole hospital nutrition intervention is feasible and will deliver more total energy compared with usual care in critically ill patients with at least one organ system failure.

METHODS AND ANALYSIS

This study is a prospective, multicentre, unblinded, parallel-group, phase II randomised controlled trial (RCT) conducted in 23 hospitals in Australia and New Zealand. Mechanically ventilated critically ill adult patients with at least one organ failure who have been in intensive care unit (ICU) for 72-120 hours and meet all of the inclusion and none of the exclusion criteria will be randomised to receive either intensive or usual nutrition care. INTENT started recruitment in October 2018 and a sample size of 240 participants is anticipated to be recruited in 2022. The study period is from randomisation to hospital discharge or study day 28, whichever occurs first, and the primary outcome is daily energy delivery from nutrition therapy. Secondary outcomes include daily energy and protein delivery during ICU and in the post-ICU period, duration of ventilation, ventilator-free days, total bloodstream infection rate and length of hospital stay. All other outcomes are considered tertiary and results will be analysed on an intention-to-treat basis.

ETHICS AND DISSEMINATION

Ethics approval has been received in Australia (Alfred Hospital Ethics Committee (HREC/18/Alfred/101) and Human Research Ethics Committee of the Northern Territory Department of Health (2019-3372)) and New Zealand (Northern A Health and Disability Ethics Committee (18/NTA/222). Results will be disseminated in an international peer-reviewed journal(s), at scientific meetings and via social media.

TRIAL REGISTRATION NUMBER

NCT03292237.

Assessment of physiological barriers to nutrition following critical illness

BACKGROUND & AIMS

Nutrition may be important for recovery from critical illness. Gastrointestinal dysfunction is a key barrier to nutrition delivery in the Intensive Care Unit (ICU) and metabolic rate is elevated exacerbating nutritional deficits. Whether these factors persist following ICU discharge is unknown. We assessed whether delayed gastric emptying (GE) and impaired glucose absorption persist post-ICU discharge.

METHODS

A prospective observational study was conducted in mechanically ventilated adults at 3 time-points: in ICU (V1); on the post-ICU ward (V2); and 3-months after ICU discharge (V3); and compared to age-matched healthy volunteers. On each visit, all participants received a test-meal containing 100 ml of 1 kcal/ml liquid nutrient, labelled with 0.1 g ¹³C-octanoic acid and 3 g 3-O-Methyl-glucose (3-OMG), and breath and blood samples were collected over 240min to quantify GE (gastric emptying coefficient (GEC)), and glucose absorption (3-OMG concentration; area under the curve (AUC)). Data are mean ± standard error of the mean (SEM) and differences shown with 95% confidence intervals (95%CI).

RESULTS

Twenty-six critically ill patients completed V1 (M:F 20:6; 62.0 ± 2.9 y; BMI 29.8 ± 1.2 kg/m²; APACHE II 19.7 ± 1.9), 15 completed V2 and eight completed V3; and were compared to 10 healthy volunteers (M:F 6:4; 60.5 ± 7.5 y; BMI 26.0 ± 1.0 kg/m²). GE was significantly slower on V1 compared to health (GEC difference: -0.96 (95%CI -1.61, -0.31); and compared to V2 (-0.73 (-1.16, -0.31) and V3 (-1.03 (-1.47, -0.59). GE at V2 and V3 were not different to that in health (V2: -0.23 (-0.61, 0.14); V3: 0.10 (-0.27, 0.46)). GEC: V1: 2.64 ± 0.19; V2: 3.37 ± 0.12; V3: 3.67 ± 0.10; health: 3.60 ± 0.13. Glucose absorption (3-OMG AUC_0-240) was impaired on V1 compared to V2 (-37.9 (-64.2, -11.6)), and faster on V3 than in health (21.8 (0.14, 43.4) but absorption at V2 and V3 did not differ from health. Intestinal glucose absorption: V1: 63.8 ± 10.4; V2: 101.7 ± 7.0; V3: 111.9 ± 9.7; health: 90.7 ± 3.8.

CONCLUSION

This study suggests that delayed GE and impaired intestinal glucose absorption recovers rapidly post-ICU. This requires further confirmation in a larger population. The REINSTATE trial was prospectively registered at www.anzctr.org.au.

TRIAL ID

ACTRN12618000370202.

Systematic review of clinicians' knowledge, attitudes, and beliefs about nutrition in intensive care

Nutrition is a key component of care for critically ill patients; yet nutrition delivery is below international recommendations. In order to improve nutrition delivery to critically ill patients, an understanding of the barriers that prevent guideline adherence is required. It is known that clinicians' knowledge, attitudes, and beliefs of the role of nutrition may act as a potential barrier to nutrition delivery, but whether this remains true in critical care is unknown. The aim of this systematic scoping review was to summarize the literature exploring the knowledge, attitudes, and beliefs of clinicians around nutrition support in critically ill patients. A search of four online databases (MEDLINE via Ovid, Emcare via Ovid, PsycINFO, and CINAHL via EBSCOhost) was conducted on August 14, 2020, to identify literature that reported on clinicians' knowledge, attitudes, and beliefs of nutrition in adult intensive care patients. Data were extracted on study and participant characteristics, methodology, and key study outcomes related to nutrition. Eighteen articles met eligibility criteria and were included in the review. Key findings included the following: nutrition was seen as a priority that ranked below life-saving interventions; differences in perceived clinician responsibilities exist; common barriers to nutrition delivery included inadequate resourcing, lack of nutrition protocols, and gastrointestinal intolerance; and identified facilitators included nutrition education and the presence of a supportive multidisciplinary team. The implementation of nutrition protocols, enhanced clinical nutrition education, and further clarification of roles and responsibilities pertaining to nutrition may assist in improving nutrition delivery in critical care.

Mixed-mode versus paper surveys for patient-reported outcomes after critical illness: A randomised controlled trial

OBJECTIVE

The aim of the study was to determine the response rate to a mixed-mode survey using email compared with that to a paper survey in survivors of critical illness.

DESIGN

This is a prospective randomised controlled trial.

SETTING

The study was conducted at a single-centre quaternary intensive care unit (ICU) in Adelaide, Australia.

PARTICIPANTS

Study participants were patients admitted to the ICU for ≥48 h and discharged from the hospital.

INTERVENTIONS

The participants were randomised to receive a survey by paper (via mail) or via online (via email, or if a non-email user, via a letter with a website address). Patients who did not respond to the initial survey received a reminder paper survey after 14 days. The survey included quality of life (EuroQol-5D-5L), anxiety and depression (Hospital Anxiety and Depression Scale), and post-traumatic symptom (Impact of Event Scale-Revised) assessment.

MAIN OUTCOME MEASURES

Survey response rate, extent of survey completion, clinical outcomes at different time points after discharge, and survey cost analysis were the main outcome measures. Outcomes were stratified based on follow-up time after ICU discharge (3, 6, and 12 months).

RESULTS

A total of 239 patients were randomised. The response rate was similar between the groups (mixed-mode: 78% [92/118 patients] vs. paper: 80% [97/121 patients], p = 0.751) and did not differ between time points of follow-up. Incomplete surveys were more prevalent in the paper group (10% vs 18%). The median EuroQol-5D-5L index value was 0.83 [0.71-0.92]. Depressive symptoms were reported by 25% of patients (46/187), anxiety symptoms were reported by 27% (50/187), and probable post-traumatic stress disorder was reported by 14% (25/184). Patient outcomes did not differ between the groups or time points of follow-up. The cost per reply was AU$ 16.60 (mixed-mode) vs AU$ 19.78 (paper).

CONCLUSION

The response rate of a mixed-mode survey is similar to that of a paper survey and may provide modest cost savings.

Nutrition-related symptoms in adult survivors of critical illness who are eating orally: a scoping review protocol

OBJECTIVE

This review will explore and map the current literature on the nutritional impact of symptoms reported by adult survivors of critical illness who are eating orally after discharge from the intensive care unit (ICU).

INTRODUCTION

Survivors of critical care often experience ICU-acquired weakness and poor functional recovery. It is plausible that nutrition interventions throughout their recovery could improve outcomes for these patients. Although a growing number of studies aim to explore the effect of nutrition delivered in the early phases of critical illness, this is also important post-ICU discharge, particularly in already nutritionally compromised patients presenting with muscle loss and fatigue. Therefore, the development of targeted nutrition interventions will be informed by a comprehensive insight into the physiological, physical, or psychological difficulties that critically ill patients experience after ICU discharge, which may impede oral intake.

INCLUSION CRITERIA

This review will consider primary research studies with adult patients 18 years and older, who are in the recovery phase after being critically ill, and eating orally. Studies must report on any symptoms related to the ability to eat, or represent nutrition inadequacy or utilization.

METHODS

A scoping review will be conducted in accordance with JBI methodology using a three-step search strategy of MEDLINE, Embase, CINAHL, AMED, Web of Science, Cochrane Database of Systematic Reviews, and JBI Evidence-based Practice Database to obtain primary research studies that meet the inclusion criteria. Duplicates will be removed, and study selection and data extraction will be conducted and cross-checked by two independent reviewers. Data synthesis will involve presenting the results in tabular form.

Effects of Standard vs Energy-Dense Formulae on Gastric Retention, Energy Delivery, and Glycemia in Critically Ill Patients

BACKGROUND

Energy-dense formulae are often provided to critically ill patients with enteral feed intolerance with the aim of increasing energy delivery, yet the effect on gastric emptying is unknown. The rate of gastric emptying of a standard compared with an energy-dense formula was quantified in critically ill patients.

METHODS

Mechanically ventilated adults were randomized to receive radiolabeled intragastric infusions of 200 mL standard (1 kcal/mL) or 100 mL energy-dense (2 kcal/mL) enteral formulae on consecutive days in this noninferiority, blinded, crossover trial. The primary outcome was scintigraphic measurement of gastric retention (percentage at 120 minutes). Other measures included area under the curve (AUC) for gastric retention and intestinal energy delivery (calculated from gastric retention of formulae over time), blood glucose (peak and AUC), and intestinal glucose absorption (using 3-O-methyl-D-gluco-pyranose [3-OMG] concentrations). Comparisons were undertaken using paired mixed-effects models. Data presented are mean ± SE.

RESULTS

Eighteen patients were studied (male/female, 14:4; age, 55.2 ± 5.3 years). Gastric retention at 120 minutes was greater with the energy-dense formula (standard, 17.0 ± 5.9 vs energy-dense, 32.5 ± 7.1; difference, 12.7% [90% confidence interval, 0.8%-30.1%]). Energy delivery (AUC₁₂₀ , 13,038 ± 1119 vs 9763 ± 1346 kcal/120 minutes; P = 0.057), glucose control (peak glucose, 10.1 ± 0.3 vs 9.7 ± 0.3 mmol/L, P = 0.362; and glucose AUC₁₂₀ 8.7 ± 0.3 vs 8.5 ± 0.3 mmol/L.120 minutes, P = 0.661), and absorption (3-OMG AUC₁₂₀ , 38.5 ± 4.0 vs 35.7 ± 4.0 mmol/L.120 minutes; P = .508) were not improved with the energy-dense formula.

CONCLUSION

In critical illness, administration of an energy-dense formula does not reduce gastric retention, increase energy delivery to the small intestine, or improve glucose absorption or glucose control; instead, there is a signal for delayed gastric emptying.

Acceleration of Gastric Emptying by Insulin-Induced Hypoglycemia is Dependent on the Degree of Hypoglycemia

CONTEXT

Hypoglycemia is a major barrier to optimal glycemic control in insulin-treated diabetes. Recent guidelines from the American Diabetes Association have subcategorized "non-severe" hypoglycemia into level 1 (<3.9 mmol/L) and 2 (<3 mmol/L) hypoglycemia. Gastric emptying of carbohydrate is a major determinant of postprandial glycemia but its role in hypoglycemia counter-regulation remains underappreciated. "Marked" hypoglycemia (~2.6 mmol/L) accelerates gastric emptying and increases carbohydrate absorption in health and type 1 diabetes, but the impact of "mild" hypoglycemia (3.0-3.9 mmol/L) is unknown.

OBJECTIVE

To determine the effects of 2 levels of hypoglycemia, 2.6 mmol/L ("marked") and 3.6 mmol/L ("mild"), on gastric emptying in health.

DESIGN, SETTING, AND SUBJECTS

Fourteen healthy male participants (mean age: 32.9 ± 8.3 years; body mass index: 24.5 ± 3.4 kg/m2) from the general community underwent measurement of gastric emptying of a radiolabeled solid meal (100 g beef) by scintigraphy over 120 minutes on 3 separate occasions, while blood glucose was maintained at either ~2.6 mmol/L, ~3.6 mmol/L, or ~6 mmol/L in random order from 15 minutes before until 60 minutes after meal ingestion using glucose-insulin clamp. Blood glucose was then maintained at 6 mmol/L from 60 to 120 minutes on all days.

RESULTS

Gastric emptying was accelerated during both mild (P = 0.011) and marked (P = 0.001) hypoglycemia when compared to euglycemia, and was more rapid during marked compared with mild hypoglycemia (P = 0.008). Hypoglycemia-induced gastric emptying acceleration during mild (r = 0.57, P = 0.030) and marked (r = 0.76, P = 0.0014) hypoglycemia was related to gastric emptying during euglycemia.

CONCLUSION

In health, acceleration of gastric emptying by insulin-induced hypoglycemia is dependent on the degree of hypoglycemia and baseline rate of emptying.

Use of a High-Protein Enteral Nutrition Formula to Increase Protein Delivery to Critically Ill Patients: A Randomized, Blinded, Parallel-Group, Feasibility Trial

BACKGROUND

International guidelines recommend critically ill adults receive more protein than most receive. We aimed to establish the feasibility of a trial to evaluate whether feeding protein to international recommendations would improve outcomes, in which 1 group received protein doses representative of international guideline recommendations (high protein) and the other received doses similar to usual practice.

METHODS

We conducted a prospective, randomized, blinded, parallel-group, feasibility trial across 6 intensive care units. Critically ill, mechanically ventilated adults expected to receive enteral nutrition (EN) for ≥2 days were randomized to receive EN containing 63 or 100 g/L protein for ≤28 days. Data are mean (SD) or median (interquartile range).

RESULTS

The recruitment rate was 0.35 (0.13) patients per day, with 120 patients randomized and data available for 116 (n = 58 per group). Protein delivery was greater in the high-protein group (1.52 [0.52] vs 0.99 [0.27] grams of protein per kilogram of ideal body weight per day; difference, 0.53 [95% CI, 0.38-0.69] g/kg/d protein), with no difference in energy delivery (difference, -26 [95% CI, -190 to 137] kcal/kg/d). There were no between-group differences in the duration of feeding (8.7 [7.3] vs 8.1 [6.3] days), and blinding of the intervention was confirmed. There were no differences in clinical outcomes, including 90-day mortality (14/55 [26%] vs 15/56 [27%]; risk difference, -1.3% [95% CI, -17.7% to 15.0%]).

CONCLUSION

Conducting a multicenter blinded trial is feasible to compare protein delivery at international guideline-recommended levels with doses similar to usual care during critical illness.

Reporting of Randomized Controlled Trials Investigating an Enteral or Parenteral Nutrition Intervention in Critical Illness According to the CONSORT Statement: A Systematic Review and Recommendation of Minimum Standard Reporting Criteria

Lack of reporting consistency is common in randomized controlled trials (RCTs) in critical care nutrition. This impacts synthesis and interpretation and may misinform clinical practice. The objective was to evaluate reporting of parallel-group RCTs of enteral or parenteral nutrition interventions in critically ill adults against the recommendations in the Consolidated Standards of Reporting Trials (CONSORT) 2010 guidelines and a priori-defined nutrition criteria. A systematic search of CENTRAL, MEDLINE, EMBASE, and CINAHL was conducted to identify RCTs published from January 2011 to February 14, 2020. The primary outcome was the percentage of CONSORT criteria "completely met" (a score of 1) from all included studies (out of a total possible score of 37). Secondary outcomes included the percentage of CONSORT criteria that were "partially" or "not met" and the percentage of a priori-defined nutrition criteria that were "completely," "partially," or "not met" (adjusted to reflect criteria applicable to the paper). Data are presented as mean (standard deviation). Comparisons of normally distributed continuous data were made using a t-test (P < .05). Of 18,969 articles identified, 56 studies met inclusion criteria. Of these, 60% (19%) of the eligible CONSORT criteria were "completely met," 20% (9%) "partially met," and 20% (15%) "not met." For the nutrition criteria, 41% (20%) of the eligible criteria were "completely met," 25% (14%) "partially met," and 34% (17%) "not met." Reporting against CONSORT guidelines was variable and often incomplete in relation to important a priori-defined nutrition variables.

A critical care pandemic staffing framework in Australia

Background

Pandemics and the large-scale outbreak of infectious disease can significantly impact morbidity and mortality worldwide. The impact on intensive care resources can be significant and often require modification of service delivery, a key element which includes rapid expansion of the critical care workforce. Pandemics are also unpredictable, which necessitates rapid decision-making and action which, in the lack of experience and guidance, may be extremely challenging. Recognising the potential strain on intensive care units (ICUs), particularly on staffing, a working group was formed for the purpose of developing recommendations to support decision-making during rapid service expansion.

Methods

The Critical Care Pandemic Staffing Working Party (n = 21), representing nursing, allied health, and medical disciplines, has used a modified consensus approach to provide recommendations to inform multidisciplinary workforce capacity expansion planning in critical care.

Results

A total of 60 recommendations have been proposed which reflect general recommendations as well as those specific to maintaining the critical care workforce, expanding the critical care workforce, rostering and allocation of the critical care workforce, nurse-specific recommendations for staffing the ICU, education support and training during ICU surge situations, workforce support, models of care, and de-escalation.

Conclusion

These recommendations are provided with the intent that they be used to guide interdisciplinary decision-making, and we suggest that careful consideration is given to the local context to determine which recommendations are most appropriate to implement and how they are prioritised. Ongoing evaluation of recommendation implementation and impact will be necessary, particularly in rapidly changing clinical contexts.

Nutrition management for critically and acutely unwell hospitalised patients with coronavirus disease 2019 (COVID-19) in Australia and New Zealand

Coronavirus disease 2019 (COVID‐19) results from severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). The clinical features and subsequent medical treatment, combined with the impact of a global pandemic, require specific nutritional therapy in hospitalised adults. This document aims to provide Australian and New Zealand clinicians with guidance on managing critically and acutely unwell adult patients hospitalised with COVID‐19. These recommendations were developed using expert consensus, incorporating the documented clinical signs and metabolic processes associated with COVID‐19, the literature from other respiratory illnesses, in particular acute respiratory distress syndrome, and published guidelines for medical management of COVID‐19 and general nutrition and intensive care. Patients hospitalised with COVID‐19 are likely to have preexisting comorbidities, and the ensuing inflammatory response may result in increased metabolic demands, protein catabolism, and poor glycaemic control. Common medical interventions, including deep sedation, early mechanical ventilation, fluid restriction, and management in the prone position, may exacerbate gastrointestinal dysfunction and affect nutritional intake. Nutrition care should be tailored to pandemic capacity, with early gastric feeding commenced using an algorithm to provide nutrition for the first 5–7 days in lower‐nutritional‐risk patients and individualised care for high‐nutritional‐risk patients where capacity allows. Indirect calorimetry should be avoided owing to potential aerosol exposure and therefore infection risk to healthcare providers. Use of a volume‐controlled, higher‐protein enteral formula and gastric residual volume monitoring should be initiated. Careful monitoring, particularly after intensive care unit stay, is required to ensure appropriate nutrition delivery to prevent muscle deconditioning and aid recovery. The infectious nature of SARS‐CoV‐2 and the expected high volume of patient admissions will require contingency planning to optimise staffing resources including upskilling, ensure adequate nutrition supplies, facilitate remote consultations, and optimise food service management. These guidelines provide recommendations on how to manage the aforementioned aspects when providing nutrition support to patients during the SARS‐CoV‐2 pandemic.

Nutrition and Gastrointestinal Dysmotility in Critically Ill Burn Patients: A Retrospective Observational Study

BACKGROUND

Gastrointestinal (GI) dysmotility impedes nutrient delivery in critically ill patients with major burns. We aimed to quantify the incidence, timing, and factors associated with GI dysmotility and subsequent nutrition delivery.

METHODS

A 10-year retrospective observational study included mechanically ventilated, adult, critically ill patients with ≥15% total body surface area (TBSA) burns receiving nutrition support. Patients with a single gastric residual volume ≥250 mL were categorized as having GI dysmotility. Daily medical and nutrition data were extracted for ≤14 days in the intensive care unit (ICU). Data are mean (SD) or median (interquartile range). Factors associated with GI dysmotility and the effect on nutrition and clinical outcomes were assessed.

RESULTS

Fifty-nine patients were eligible; 51% (n = 30) with GI dysmotility and 49% (n = 29) without. Baseline characteristics (dysmotility vs no dysmotility) were age (48 [33-60] vs 34 [26-46] years); Acute Physiology and Chronic Health Evaluation II score (16 [12-17] vs 13 [10-16]); sex ([men] 80% vs 86%); and TBSA (49% [35%-59%] vs 38% [26%-55%]). Older age was associated with increased probability of dysmotility (P = .049). GI dysmotility occurred 32 (19-63) hours after ICU admission but was not associated with reduced nutrient delivery. Postpyloric tube insertions were attempted in 83% (n = 25) of patients, with 72% (n = 18) being successful. Postpyloric feeding achieved higher nutrition adequacy than gastric feeding (energy: 82% [95% CI, 70-94] vs 68% [95% CI, 63-74], P = .036; protein: 75% [95% CI, 65-86] vs 61% [95% CI, 56-65], P = .009).

CONCLUSION

GI dysmotility occurs early in critically ill burn patients, and postpyloric feeding improves nutrition delivery.

Early anthropometry, strength, and function in survivors of critical illness

BACKGROUND

Critically ill patients experience acute muscle wasting and long-term functional impairments, yet this has been inadequately categorised early in recovery.

OBJECTIVE

This observational study aimed to evaluate anthropometry, strength, and muscle function after intensive care unit discharge.

METHODS

Adult patients able to complete study measures after prolonged intensive care unit stay (≥5 d) were eligible. Demographic and clinical data were collected, and bodyweight, height, triceps skinfold, trunk length, handgrip strength, 6-minute walk test, whole-body dual-energy x-ray absorptiometry, and mid-thigh, knee, and above-ankle circumferences were measured. Body cell mass was calculated from these data. Data are presented as mean (standard deviation) or median [interquartile range].

RESULTS

Fourteen patients (50% male; 57 [10.5] years) were assessed 11.1 (6.9) d after intensive care unit discharge. Patients lost 4.76 (6.66) kg in the intensive care unit. Triceps skinfold thickness (17.00 [8.65] mm) and handgrip strength (12.60 [8.57] kg) were lower than normative data. No patient could commence the 6-minute walk test. Dual-energy x-ray absorptiometry-derived muscle mass correlated with handgrip strength (R = 0.57; 95% confidence interval = 0.06-0.85; p = 0.03), but body cell mass did not.

CONCLUSIONS

Anthropometry and strength in intensive care unit survivors are below normal. Muscle mass derived from dual-energy x-ray absorptiometry correlates with handgrip strength but body cell mass does not.

Nutrition intake in the post-ICU hospitalization period

PURPOSE OF REVIEW

The care of critically ill patients has evolved over recent years, resulting in significant reductions in mortality in developed countries; sometimes with prolonged issues with recovery. Nutrition research has focused on the early, acute period of critical illness, until more recently, where the post-ICU hospitalization period in critical care survivors has become a focus for nutrition rehabilitation. In this period, nutrition rehabilitation may be a vital component of recovery.

RECENT FINDINGS

Overall, oral nutrition is the most common mode of nutrition provision in the post-ICU period. Compared with oral intake alone, calorie and protein requirements can be better met with the addition of oral supplements and/or enteral nutrition to oral intake. However, calorie and protein intake remains below predicted targets in the post-ICU hospitalization period. Achieving nutrition targets are complex and multifactorial, but can primarily be grouped into three main areas: patient factors; clinician factors; and system factors.

SUMMARY

A nutrition intervention in the post-ICU hospitalization period may provide an opportunity to improve survival and functional recovery. However, there are multiple barriers to the delivery of calculated nutrition requirements in this period, a limited understanding of how this can be improved and how this translates into clinical benefit.

Clinical Sequelae From Overfeeding in Enterally Fed Critically Ill Adults: Where Is the Evidence?

Enteral energy delivery above requirements (overfeeding) is believed to cause adverse effects during critical illness, but the literature supporting this is limited. We aimed to quantify the reported frequency and clinical sequelae of energy overfeeding with enterally delivered nutrition in critically ill adult patients. A systematic search of MEDLINE, EMBASE, and CINAHL from conception to November 28, 2018, identified clinical studies of nutrition interventions in enterally fed critically ill adults that reported overfeeding in 1 or more study arms. Overfeeding was defined as energy delivery > 2000 kcal/d, > 25 kcal/kg/d, or ≥ 110% of energy prescription. Data were extracted on methodology, demographics, prescribed and delivered nutrition, clinical variables, and predefined outcomes. Cochrane "Risk of Bias" tool was used to assess the quality of randomized controlled trials (RCTs). Eighteen studies were included, of which 10 were randomized (n = 4386 patients) and 8 were nonrandomized (n = 223). Only 4 studies reported a separation in energy delivery between treatment groups whereby 1 arm met the definition of overfeeding, which reported no between-group differences in mortality, infectious complications, or ventilatory support. Overfeeding was associated with increased insulin administration (median 3 [interquartile range: 0-41.8] vs 0 [0-30.6] units/d) and upper-gastrointestinal intolerance in 1 large RCT and with duration of antimicrobial therapy in a small RCT. There are limited high-quality data to determine the impact of energy overfeeding of critically ill patients by the enteral route; however, based on available evidence, overfeeding does not appear to affect mortality or other important clinical outcomes.

Systematic Review With Meta-Analysis of Patient-Centered Outcomes, Comparing International Guideline-Recommended Enteral Protein Delivery With Usual Care

BACKGROUND

International guidelines recommend that protein be administered enterally to critically ill patients at doses between 1.2 and 2 g/kg per day Observational data indicate that patients frequently receive less protein. The aim of this systematic review was to evaluate patient-centered outcomes with guideline-recommended enteral protein compared with usual care.

METHODS

A systematic review was performed of randomized controlled trials including critically ill adult patients provided predominately enteral nutrition with mean protein at ≥1.2 g/kg per day (intervention) and <1.2 g/kg per day (comparator). Random-effects models were applied for outcomes reported in ≥3 trials.

RESULTS

Of 1375 abstracts, 69 full-text articles were reviewed, and 6 trials meet the inclusion criteria, including 511 patients. The intervention group received a mean (SD) of 1.3 (0.08) g/kg per day, and the comparator group received 0.75 (0.15) g/kg per day protein. Insufficient data were available for meta-analyses on the primary outcome (muscle mass or strength). According to our meta-analyses, mortality at 28 days (5 studies) (risk ratio 0.92 [95% Cl 0.63-1.35], P = .66) and the durations of intensive care unit (6 studies) and hospital admission (4 studies) were similar between the intervention and comparator, with some uncertainty due to sample sizes and heterogeneity.

CONCLUSION

There are insufficient data to conclude whether protein provision within the current international guideline recommendations improves outcomes. In a limited dataset, enteral protein intakes near the lower level of current recommendations do not appear to reduce admission duration or mortality when compared with usual care in critically ill.

Exploring the Potential Effectiveness of Combining Optimal Nutrition With Electrical Stimulation to Maintain Muscle Health in Critical Illness: A Narrative Review

Muscle wasting occurs rapidly within days of an admission to the intensive care unit (ICU). Concomitant muscle weakness and impaired physical functioning can ensue, with lasting effects well after hospital discharge. Early physical rehabilitation is a promising intervention to minimize muscle weakness and physical dysfunction. However, there is an often a delay in commencing active functional exercises (such as sitting on the edge of bed, standing and mobilizing) due to sedation, patient alertness, and impaired ability to cooperate in the initial days of ICU admission. Therefore, there is high interest in being able to intervene early through nonvolitional exercise strategies such as electrical muscle stimulation (EMS). Muscle health characterized as the composite of muscle quantity, as well as functional and metabolic integrity, may be potentially maintained when optimal nutrition therapy is provided in complement with early physical rehabilitation in critically ill patients; however, the type, dosage, and timing of these interventions are unclear. This article explores the potential role of nutrition and EMS in maintaining muscle health in critical illness. Within this article, we will evaluate fundamental concepts of muscle wasting and evaluate the effects of EMS, as well as the effects of nutrition therapy on muscle health and the clinical and functional outcomes in critically ill patients. We will also highlight current research gaps in order to advance the field forward in this important area.

Observed appetite and nutrient intake three months after ICU discharge

BACKGROUND & AIMS

Oral intake is diminished immediately after ICU discharge, yet factors affecting nutritional intake after hospital discharge have not been evaluated. The aim of this study was to evaluate dietary intake and factors which may influence intake - appetite and gastric emptying - 3-months after ICU discharge.

METHODS

Inception cohort study with ICU survivors compared to healthy subjects. Following an overnight fast, all participants consumed a standardized carbohydrate drink, containing ¹³C-octanoic acid, to measure gastric emptying. Dietary intake was assessed by recall of the preceding day and a standard weighed buffet meal 4-h post-drink. Appetite was assessed pre-drink (fasting) and pre- and post-buffet using visual analogue scales.

RESULTS

Fifty-one ICU survivors (82% male; 70 ± 9 y; BMI 28 ± 6 kg/m²) and 25 healthy subjects (60% male; 67 ± 12 y; BMI 27 ± 4 kg/m²) were evaluated. From the 24-h recall ICU survivors consumed less calories (ICU 1876 (708) vs. healthy subjects 2291 (834) kcal; p = 0.025) with no difference in macronutrient intake, however reported a lower preference for fat (p < 0.001). Calorie and macronutrient intake from the weighed buffet was similar between groups: calories (ICU: 658 (301) vs. healthy subjects: 736 (325) kcal; p = 0.149); protein (ICU: 37 (19) vs. healthy subjects: 40 (17) g; p = 0.275); fat (ICU: 23 (12) vs healthy subjects: 26 (13) g; p = 0.261); and carbohydrates (ICU: 69 (35) vs. healthy subjects: 79 (42) g; p = 0.141). ICU survivors reported feeling less full regardless of time-point (p = 0.041). There was no difference in the rate of gastric emptying between the two groups (p = 0.216).

CONCLUSIONS

ICU survivors reported less preference for fat and less calorie consumption than healthy subjects. However, intake of calories and macronutrients at a weighed meal was similar in the two groups, as was the rate of gastric emptying. ICU survivors reported being less full after the test meal, suggesting factors other than appetite may influence intake.

A scoping review of use of wearable devices to evaluate outcomes in survivors of critical illness

OBJECTIVE

Wearable devices using new technology may be a cost-effective method to assess functional outcomes in survivors of critical illness. Our primary objective was to review the extent to which wearable devices such as smartphones, pedometers, accelerometers and global positioning systems have been used to evaluate outcomes in survivors of an intensive care unit admission.

DESIGN

We included studies of patients surviving an ICU admission and which measured outcomes using wearable devices. We performed a scoping review of studies found by searching the CINAHL, Embase, MEDLINE and PubMed databases.

RESULTS

The seven studies we identified were published in or after 2012 and were predominantly descriptive (n = 6) with one randomised controlled trial. All studies described outcomes in cohorts of relatively few participants (range, 11-51 participants). Duration to follow-up was mostly short, at a median time of 3 months after ICU discharge (range, in-hospital to 27 years). All studies used accelerometers to monitor patient movement: physical activity (n = 5), sleep quality (n = 1), and infant movement (n = 1). The accelerometers were bi-axial (n = 3), uni-axial (n = 2) combined uni-axial (n = 1) and tri-axial (n = 1). Common outcomes evaluated were the number of participants walking for < 30 min/day, mean daily step count and walking speed.

CONCLUSIONS

Wearable devices have infrequently been used to measure physical activity in survivors of critical illness and all identified studies were published recently, which suggests that the use of wearable devices for research may be increasing. To date, only accelerometry has been reported, and the wide variation in methodologies used and the outcomes measured limits synthesis of these data.

Longitudinal changes in anthropometrics and impact on self-reported physical function after traumatic brain injury

BACKGROUND AND AIMS

Patients admitted to the ICU with a traumatic brain injury (TBI) are at risk of muscle wasting but this has not been quantified. Our aims were to describe longitudinal changes in anthropometrical data, compare the accuracy of non-invasive methodologies to the validated dual-energy x-ray absorptiometry (DXA), and assess the relationships between anthropometrical data and self-reported physical function.

METHODS

In a prospective observational study, we recruited patients admitted to the ICU with a moderate-to-severe TBI over 12 months. Anthropometric measurements included the subjective global assessment (SGA), bodyweight and ultrasoundderived quadriceps muscle layer thickness (QMLT), which we performed weekly in hospital and 3 months after admission. We assessed total body composition using DXA within 7 days of ICU discharge, and compared the total lean muscle mass with ultrasound-derived QMLT taken within 5 days of the DXA measurement. We assessed functional outcomes at 3 months using the physical component score of the Short Form-36 (SF- 36) and the Extended Glasgow Outcome Scale (GOS-E).

RESULTS

Thirty-seven patients were included, with a mean age of 45 years (SD, 16 years), and 87% were men. Participants were admitted to the ICU for a mean of 13 days (IQR, 6-18 days) and to hospital for a mean of 38 days (IQR, 19-52 days). They had significant weight loss in hospital (mean, 4.9% [SD, 7.7%]; P = 0.001). Malnutrition, measured with the SGA, was twice as prevalent at hospital discharge than at admission (P = 0.005). A reduction in QMLT occurred in the ICU but stabilised after ICU discharge. DXA-derived total lean mass taken within 7 days of ICU discharge strongly correlated with ultrasound-derived QMLT taken within 5 days of DXA measurements (ρ = 0.74, P = 0.037). Improvements in self-reported physical function, using the SF- 36 and GOS-E at 3 months, were associated with a greater QMLT at hospital discharge (SF-36: ρ = 0.536, P = 0.010; GOS-E: ρ = 0.595, P = 0.003, n = 23) and at 3 months (SF-36: ρ = 0.658, P = 0.020; GOS-E: ρ = 0.642, P = 0.025, n = 12).

CONCLUSIONS

Patients with a TBI lose muscle thickness while in the ICU but the trajectory of loss stabilises after ICU discharge. Ultrasound-derived QMLT is related to total lean mass and physical function after discharge. Further studies are needed to confirm that ultrasound measurement of QMLT is a useful surrogate measure of muscle mass and functional outcomes after trauma and critical illness.

Exogenous glucagon-like peptide-1 attenuates glucose absorption and reduces blood glucose concentration after small intestinal glucose delivery in critical illness

OBJECTIVE

To evaluate the effect of exogenous glucagonlike peptide-1 (GLP-1) on small intestinal glucose absorption and blood glucose concentrations during critical illness.

DESIGN, SETTING AND PARTICIPANTS

A prospective, blinded, placebo-controlled, cross-over, randomised trial in a mixed medical-surgical adult intensive care unit, with 12 mechanically ventilated critically ill patients, who were suitable for receiving small intestinal nutrient.

INTERVENTIONS

On consecutive days, in a randomised order, participants received intravenous GLP-1 (1.2 pmol/ kg/min) or placebo (0.9% saline) as a continuous infusion over 270 minutes. After 6 hours of fasting, intravenous infusions of GLP-1 or placebo began at T = -30 min (in which T = time), with the infusion maintained at a constant rate until study completion at T = 240 min. At T = 0 min, a 100 mL bolus of mixed liquid nutrient meal (1 kcal/mL) containing 3 g of 3-O-methyl-D-gluco-pyranose (3-OMG), a marker of glucose absorption, was administered directly into the small intestine, via a post-pyloric catheter, over 6 minutes.

MAIN OUTCOME MEASURES

Blood samples were taken at regular intervals for the measurement of plasma glucose and 3-OMG concentrations.

RESULTS

Intravenous GLP-1 attenuated initial small intestinal glucose absorption (mean area under the curve [AUC]_0-30 for 3-OMG: GLP-1 group, 4.4 mmol/L/min [SEM, 0.9 mmol/L/min] v placebo group, 6.5 mmol/L/min [SEM, 1.0 mmol/L/min]; P = 0.01), overall small intestinal glucose absorption (mean AUC_0-240 for 3-OMG: GLP-1, 68.2 mmol/L/ min [SEM, 4.7 mmol/L/min] v placebo, 77.7 mmol/L/min [SEM, 4.4 mmol/lLmin]; P = 0.02), small intestinal glucose absorption and overall blood glucose concentration (mean AUC_0-240 for blood glucose: GLP-1, 2062 mmol/L/min [SEM, 111 mmol/L/min] v placebo 2328 mmol/L/min [SEM, 145 mmol/L/min]; P = 0.005).

CONCLUSIONS

Short-term administration of exogenous GLP-1 reduces small intestinal glucose absorption for up to 4 hours during critical illness. This is likely to be an additional mechanism for the glucose-lowering effect of this agent.

A prospective observational study of the effect of critical illness on ultrastructural and microscopic morphology of duodenal mucosa

OBJECTIVE

Disturbed intestinal barrier function due to 'leaky' tight junctions may cause secondary sepsis via paracellular translocation across the gut wall. Our objective was to describe the effects of critical illness on duodenal morphology and ultrastructure.

DESIGN, SETTING AND PARTICIPANTS

Prospective observational study of 12 mechanically ventilated critically ill patients in an intensive care unit and 15 control participants in an outpatient endoscopy suite.

INTERVENTION

We took six endoscopic biopsy samples of the duodenum from each participant for analysis by electron and light microscopy.

MAIN OUTCOME MEASURES

Our primary outcome was tight junction morphology, examined with electron microscopy. Secondary outcomes were microvillus length and density, vascular endothelium morphology and mitochondrial density and morphology, examined with electron microscopy, and morphology examined with light microscopy.

RESULTS

We observed no abnormalities of tight junction ultrastructure in either group. There was a tendency towards shorter microvilli in the critically ill group: mean length in critically ill patients, 1.17 µm (interquartile range [IQR], 1.05-1.60 µm) v mean length in control patients, 1.58 µm (IQR, 1.30-1.72 µm); P = 0.07. There was a tendency towards less dense microvilli in the critically ill group: mean density in critically ill patients, 7.29 microvilli/µm (IQR, 6.83-8.05 microvilli/µm) v mean density in control patients, 8.23 microvilli/µm (IQR, 7.34-9.11 microvilli/µm); P = 0.07. Vascular endothelium appeared normal in all critically ill patients and abnormal in one control participant. Abnormal mitochondrial morphology was noted in one critically ill patient and one control participant, and no differences were seen in mitochondrial density. Using light microscopy, we saw more apoptotic cells in the critically ill patients (P = 0.018), but villus height, crypt depth and lymphocyte density were normal.

CONCLUSIONS

We did not detect any morphological abnormalities of duodenal tight junctions in critically ill patients. Our results should be interpreted with caution because of the small sample population, but our observations challenge the concept that paracellular translocation facilitates secondary sepsis.

Energy and protein deficits throughout hospitalization in patients admitted with a traumatic brain injury

BACKGROUND AND AIMS

Patients with traumatic brain injury (TBI) experience considerable energy and protein deficits in the intensive care unit (ICU) and these are associated with adverse outcomes. However, nutrition delivery after ICU discharge during ward-based care, particularly from oral diet, has not been measured. This study aimed to quantify energy and protein delivery and deficits over the entire hospitalization for critically ill TBI patients.

METHODS

Consecutively admitted adult patients with a moderate-severe TBI (Glasgow Coma Scale 3-12) over 12 months were eligible. Observational data on energy and protein delivered from all routes were collected until hospital discharge or day 90 and compared to dietician prescriptions. Oral intake was quantified using weighed food records on three pre-specified days each week. Data are mean (SD) unless indicated. Cumulative deficit is the mean absolute difference between intake and estimated requirements.

RESULTS

Thirty-seven patients [45.3 (15.8) years; 87% male; median APACHE II 18 (IQR: 14-22)] were studied for 1512 days. Median duration of ICU and ward-based stay was 13.4 (IQR: 6.4-17.9) and 19.9 (9.6-32.0) days, respectively. Over the entire hospitalization patients had a cumulative deficit of 18,242 (16,642) kcal and 1315 (1028) g protein. Energy and protein intakes were less in ICU than the ward (1798 (800) vs 1980 (915) kcal/day, p = 0.015; 79 (47) vs 89 (41) g/day protein, p = 0.001). Energy deficits were almost two-fold greater in patients exclusively receiving nutrition orally than tube-fed (806 (616) vs 445 (567) kcal/day, p = 0.016) while protein deficits were similar (40 (5) vs 37 (6) g/day, p = 0.616). Primary reasons for interruptions to enteral and oral nutrition were fasting for surgery/procedures and patient-related reasons, respectively.

CONCLUSIONS

Patients admitted to ICU with a TBI have energy and protein deficits that persist after ICU discharge, leading to considerable shortfalls over the entire hospitalization. Patients ingesting nutrition orally are at particular risk of energy deficit.

Nutrition support practices in critically ill head-injured patients: a global perspective

Background

Critical illness following head injury is associated with a hypermetabolic state but there are insufficient epidemiological data describing acute nutrition delivery to this group of patients. Furthermore, there is little information describing relationships between nutrition and clinical outcomes in this population.

Methods

We undertook an analysis of observational data, collected prospectively as part of International Nutrition Surveys 2007-2013, and extracted data obtained from critically ill patients with head trauma. Our objective was to describe global nutrition support practices in the first 12 days of hospital admission after head trauma, and to explore relationships between energy and protein intake and clinical outcomes. Data are presented as mean (SD), median (IQR), or percentages.

Results

Data for 1045 patients from 341 ICUs were analyzed. The age of patients was 44.5 (19.7) years, 78 % were male, and median ICU length of stay was 13.1 (IQR 7.9-21.6) days. Most patients (94 %) were enterally fed but received only 58 % of estimated energy and 53 % of estimated protein requirements. Patients from an ICU with a feeding protocol had greater energy and protein intakes (p <0.001, 0.002 respectively) and were more likely to survive (OR 0.65; 95 % CI 0.42-0.99; p = 0.043) than those without. Energy or protein intakes were not associated with mortality. However, a greater energy and protein deficit was associated with longer times until discharge alive from both ICU and hospital (all p <0.001).

Conclusion

Nutritional deficits are commonplace in critically ill head-injured patients and these deficits are associated with a delay to discharge alive.