A secondary atmosphere on the rocky exoplanet 55 Cancri e.

Characterizing rocky exoplanets is a central aim of astronomy, and yet the search for atmospheres on rocky exoplanets has so far resulted in either tight upper limits on the atmospheric mass1-3 or inconclusive results4-6. The 1.95REarth and 8.8MEarth planet 55 Cancri e (abbreviated 55 Cnc e), with a predominantly rocky composition and an equilibrium temperature of around 2,000 K, may have a volatile envelope (containing molecules made from a combination of C, H, O, N, S and P elements) that accounts for up to a few percent of its radius7-13. The planet has been observed extensively with transmission spectroscopy14-22 and its thermal emission has been measured in broad photometric bands23-26. These observations disfavour a primordial H2/He-dominated atmosphere but cannot conclusively determine whether the planet has a secondary atmosphere27,28. Here we report a thermal emission spectrum of the planet obtained by the NIRCam and MIRI instruments aboard the James Webb Space Telescope (JWST) from 4 to 12 µm. The measurements rule out the scenario in which the planet is a lava world shrouded by a tenuous atmosphere made of vaporized rock29-32 and indicate a bona fide volatile atmosphere that is probably rich in CO2 or CO. This atmosphere can be outgassed from and sustained by a magma ocean.

The effect of higher protein dosing in critically ill patients with high nutritional risk (EFFORT Protein): an international, multicentre, pragmatic, registry-based randomised trial.

BACKGROUND: On the basis of low-quality evidence, international critical care nutrition guidelines recommend a wide range of protein doses. The effect of delivering high-dose protein during critical illness is unknown. We aimed to test the hypothesis that a higher dose of protein provided to critically ill patients would improve their clinical outcomes. METHODS: This international, investigator-initiated, pragmatic, registry-based, single-blinded, randomised trial was undertaken in 85 intensive care units (ICUs) across 16 countries. We enrolled nutritionally high-risk adults (≥18 years) undergoing mechanical ventilation to compare prescribing high-dose protein (≥2·2 g/kg per day) with usual dose protein (≤1·2 g/kg per day) started within 96 h of ICU admission and continued for up to 28 days or death or transition to oral feeding. Participants were randomly allocated (1:1) to high-dose protein or usual dose protein, stratified by site. As site personnel were involved in both prescribing and delivering protein dose, it was not possible to blind clinicians, but patients were not made aware of the treatment assignment. The primary efficacy outcome was time-to-discharge-alive from hospital up to 60 days after ICU admission and the secondary outcome was 60-day morality. Patients were analysed in the group to which they were randomly assigned regardless of study compliance, although patients who dropped out of the study before receiving the study intervention were excluded. This study is registered with ClinicalTrials.gov, NCT03160547. FINDINGS: Between Jan 17, 2018, and Dec 3, 2021, 1329 patients were randomised and 1301 (97·9%) were included in the analysis (645 in the high-dose protein group and 656 in usual dose group). By 60 days after randomisation, the cumulative incidence of alive hospital discharge was 46·1% (95 CI 42·0%-50·1%) in the high-dose compared with 50·2% (46·0%-54·3%) in the usual dose protein group (hazard ratio 0·91, 95% CI 0·77-1·07; p=0·27). The 60-day mortality rate was 34·6% (222 of 642) in the high dose protein group compared with 32·1% (208 of 648) in the usual dose protein group (relative risk 1·08, 95% CI 0·92-1·26). There appeared to be a subgroup effect with higher protein provision being particularly harmful in patients with acute kidney injury and higher organ failure scores at baseline. INTERPRETATION: Delivery of higher doses of protein to mechanically ventilated critically ill patients did not improve the time-to-discharge-alive from hospital and might have worsened outcomes for patients with acute kidney injury and high organ failure scores. FUNDING: None.

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.

Recent Advances in Management of Neuropathic, Nociceptive, and Chronic Pain: A Narrative Review with Focus on Nanomedicine, Gene Therapy, Stem Cell Therapy, and Newer Therapeutic Options.

PURPOSE OF REVIEW: This manuscript summarizes novel clinical and interventional approaches in the management of chronic, nociceptive, and neuropathic pain. RECENT FINDINGS: Pain can be defined as a feeling of physical or emotional distress caused by an external stimulus. Pain can be grouped into distinct types according to characteristics including neuropathic pain, which is a pain caused by disease or lesion in the sensory nervous system; nociceptive pain, which is pain that can be sharp, aching, or throbbing and is caused by injury to bodily tissues; and chronic pain, which is long lasting or persisting beyond 6 months. With improved understanding of different signaling systems for pain in recent years, there has been an upscale of methods of analgesia to counteract these pathological processes. Novel treatment methods such as use of cannabinoids, stem cells, gene therapy, nanoparticles, monoclonal antibodies, and platelet-rich plasma have played a significant role in improved strategies for therapeutic interventions. Although many management options appear to be promising, extensive additional clinical research is warranted to determine best practice strategies in the future for clinicians.

The Efficacy of Glutamine Supplementation in Severe Adult Burn Patients: A Systematic Review With Trial Sequential Meta-Analysis.

OBJECTIVES: Evidence supporting glutamine supplementation in severe adult burn patients has created a state of uncertainty due to the variability in the treatment effect reported across small and large randomized controlled trials (RCTs). We aimed to systematically review the effect of glutamine supplementation on mortality in severe adult burn patients. DATA SOURCES: MEDLINE, Embase, CINAHL, and Cochrane Central were searched from inception to February 10, 2023. STUDY SELECTION: RCTs evaluating the effect of enteral or IV glutamine supplementation alone in severe adult burn patients were included. DATA EXTRACTION: Two reviewers independently extracted data on study characteristics, burn injury characteristics, description of the intervention between groups, adverse events, and clinical outcomes. DATA SYNTHESIS: Random effects meta-analyses were performed to estimate the pooled risk ratio (RR). Trial sequential analyses (TSA) for mortality and infectious complications were performed. Ten RCTs (1,577 patients) were included. We observed no significant effect of glutamine supplementation on overall mortality (RR, 0.65, 95% CI, 0.33-1.28; p = 0.21), infectious complications (RR, 0.83; 95% CI, 0.63-1.09; p = 0.18), or other secondary outcomes. In subgroup analyses, we observed no significant effects based on administration route or burn severity. We did observe a significant subgroup effect between single and multicenter RCTs in which glutamine significantly reduced mortality and infectious complications in singe-center RCTs but not in multicenter RCTs. However, TSA showed that the pooled results of single-center RCTs were type 1 errors and further trials would be futile. CONCLUSIONS: Glutamine supplementation, regardless of administration, does not appear to improve clinical outcomes in severely adult burned patients.

The impact of higher protein dosing on outcomes in critically ill patients with acute kidney injury: a post hoc analysis of the EFFORT protein trial.

BACKGROUND: Based on low-quality evidence, current nutrition guidelines recommend the delivery of high-dose protein in critically ill patients. The EFFORT Protein trial showed that higher protein dose is not associated with improved outcomes, whereas the effects in critically ill patients who developed acute kidney injury (AKI) need further evaluation. The overall aim is to evaluate the effects of high-dose protein in critically ill patients who developed different stages of AKI. METHODS: In this post hoc analysis of the EFFORT Protein trial, we investigated the effect of high versus usual protein dose (≥ 2.2 vs. ≤ 1.2 g/kg body weight/day) on time-to-discharge alive from the hospital (TTDA) and 60-day mortality and in different subgroups in critically ill patients with AKI as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria within 7 days of ICU admission. The associations of protein dose with incidence and duration of kidney replacement therapy (KRT) were also investigated. RESULTS: Of the 1329 randomized patients, 312 developed AKI and were included in this analysis (163 in the high and 149 in the usual protein dose group). High protein was associated with a slower time-to-discharge alive from the hospital (TTDA) (hazard ratio 0.5, 95% CI 0.4-0.8) and higher 60-day mortality (relative risk 1.4 (95% CI 1.1-1.8). Effect modification was not statistically significant for any subgroup, and no subgroups suggested a beneficial effect of higher protein, although the harmful effect of higher protein target appeared to disappear in patients who received kidney replacement therapy (KRT). Protein dose was not significantly associated with the incidence of AKI and KRT or duration of KRT. CONCLUSIONS: In critically ill patients with AKI, high protein may be associated with worse outcomes in all AKI stages. Recommendation of higher protein dosing in AKI patients should be carefully re-evaluated to avoid potential harmful effects especially in patients who were not treated with KRT. TRIAL REGISTRATION: This study is registered at ClinicalTrials.gov (NCT03160547) on May 17th 2017.

A randomised controlled trial of a nutrition and a decision support intervention to enable partnerships with families of critically ill patients.

AIMS AND OBJECTIVES: The aim of the study was to investigate the effect of supporting family members to partner with health professionals on nutrition intakes and decision-making and to evaluate intervention and study feasibility. BACKGROUND: Family partnerships can improve outcomes for critically ill patients and family members. Interventions that support families to engage with health professionals require evaluation. DESIGN: A multi-centre, randomised, parallel group superiority Phase II randomised controlled trial. METHODS: In nine intensive care units (ICUs) across three countries, critically ill patients ≥60 years, or those 55-59 years with advanced chronic diseases and expected ICU length of stay >72 h and their family member were enrolled between 9 May 2017 and 31 March 2020. Participants were randomised (1:1:1) to either a decision support or nutrition optimisation family-centred intervention, or usual care. Primary outcomes included protein and energy intake during ICU and hospital stay (nutrition intervention) and family satisfaction (decision support). Study feasibility was assessed as a composite of consent rate, intervention adherence, contamination and physician awareness of intervention assignment. RESULTS: We randomised 135 patients/family members (consent rate 51.7%). The average rate of randomisation was 0.5 (0.13-1.53) per month. Unavailability (staff/family) was the major contributor to families not being approached for consent. Declined consent was attributed to families feeling overwhelmed (58/126, 46%). Pandemic visitor restrictions contributed to early study cessation. Intervention adherence for the decision support intervention was 76.9%-100.0% and for the nutrition intervention was 44.8%-100.0%. Nutritional adequacy, decisional conflict, satisfaction with decision-making and overall family satisfaction with ICU were similar for all groups. CONCLUSIONS: Active partnerships between family members and health professionals are important but can be challenging to achieve in critical care contexts. We were unable to demonstrate the efficacy of either intervention. Feasibility outcomes suggest further refinement of interventions and study protocol may be warranted. RELEVANCE TO CLINICAL PRACTICE: Interventions to promote family partnerships in critical illness are needed but require a greater understanding of the extent to which families want and are able to engage and the activities in which they have most impact. REPORTING METHOD: This study has been reported following the Consolidated Standards of Reporting Trials (CONSORT) and the Template for Intervention Description and Replication (TIDieR) guidelines. PATIENT OR PUBLIC CONTRIBUTION: Patients and caregivers were engaged in and contributed to the development and subsequent iterations of the two family-centred interventions use in this study. CLINICAL TRIAL REGISTRATION NUMBER: Trial registration. CLINICALTRIALS: gov, ID: NCT02920086. Registered on 30 September 2016. First patient enrolled on 9 May 2017 https://clinicaltrials.gov/ct2/results?cond=&term=NCT02920086&cntry=&state=&city=&dist=.

A Mixed-Methods Feasibility Study: Eliciting ICU Experiences and Measuring Outcomes of Family Caregivers of Patients Who Have Undergone Hematopoietic Stem Cell Transplantation.

The impact of an intensive care unit (ICU) admission on family caregivers of patients who have undergone hematopoietic stem cell transplantation (HSCT) has not been well described. Aims of this study were to determine the feasibility of conducting research with family caregivers of HSCT patients during an ICU admission and generate preliminary data about their experiences and engagement in care. Using a mixed-methods, repeated measures design, we collected data from family caregivers after 48 hr in the ICU (T1) and at 48 hr after transferring out of ICU (T2). Enrolling HSCT caregivers in research while in the ICU was feasible (10/13 consented; 9/10 completed data collection at T1); however, data collection at T2 was not possible for most caregivers. Caregiver distress levels were high, and engagement in care was moderate. The three themes that emerged from interviews (n = 5) highlighted that although HSCT family caregivers faced many challenges and received limited support during their ICU experience, they were able to access their own personal resources and demonstrated resilience.

Critical Appraisal of a Systematic Review: A Concise Review.

OBJECTIVES: Concise definitive review of how to read and critically appraise a systematic review. DATA SOURCES: None. STUDY SELECTION: Current literature describing the conduct, reporting, and appraisal of systematic reviews and meta-analyses. DATA EXTRACTION: Best practices for conducting, reporting, and appraising systematic review were summarized. DATA SYNTHESIS: A systematic review is a review of a clearly formulated question that uses systematic and explicit methods to identify, select, and critically appraise relevant original research, and to collect and analyze data from the studies that are included in the review. Critical appraisal methods address both the credibility (quality of conduct) and rate the confidence in the quality of summarized evidence from a systematic review. The A Measurement Tool to Assess Systematic Reviews-2 tool is a widely used practical tool to appraise the conduct of a systematic review. Confidence in estimates of effect is determined by assessing for risk of bias, inconsistency of results, imprecision, indirectness of evidence, and publication bias. CONCLUSIONS: Systematic reviews are transparent and reproducible summaries of research and conclusions drawn from them are only as credible and reliable as their development process and the studies which form the systematic review. Applying evidence from a systematic review to patient care considers whether the results can be directly applied, whether all important outcomes have been considered, and if the benefits are worth potential harms and costs.

IV Vitamin C in Critically Ill Patients: A Systematic Review and Meta-Analysis.

OBJECTIVES: To conduct a systematic review and meta-analysis to evaluate the impact of IV vitamin C on outcomes in critically ill patients. DATA SOURCES: Systematic search of MEDLINE, EMBASE, CINAHL, and the Cochrane Register of Controlled Trials. STUDY SELECTION: Randomized controlled trials testing IV vitamin C in critically ill patients. DATA ABSTRACTION: Two independent reviewers abstracted patient characteristics, treatment details, and clinical outcomes. DATA SYNTHESIS: Fifteen studies involving 2,490 patients were identified. Compared with placebo, IV vitamin C administration is associated with a trend toward reduced overall mortality (relative risk, 0.87; 95% CI, 0.75-1.00; p = 0.06; test for heterogeneity I2 = 6%). High-dose IV vitamin C was associated with a significant reduction in overall mortality (relative risk, 0.70; 95% CI, 0.52-0.96; p = 0.03), whereas low-dose IV vitamin C had no effect (relative risk, 0.94; 95% CI, 0.79-1.07; p = 0.46; test for subgroup differences, p = 0.14). IV vitamin C monotherapy was associated with a significant reduction in overall mortality (relative risk, 0.64; 95% CI, 0.49-0.83; p = 0.006), whereas there was no effect with IV vitamin C combined therapy. No trial reported an increase in adverse events related to IV vitamin C. CONCLUSIONS: IV vitamin C administration appears safe and may be associated with a trend toward reduction in overall mortality. High-dose IV vitamin C monotherapy may be associated with improved overall mortality, and further randomized controlled trials are warranted.

Early versus delayed enteral nutrition in mechanically ventilated patients with circulatory shock: a nested cohort analysis of an international multicenter, pragmatic clinical trial.

INTRODUCTION: Real-world evidence on the timing and efficacy of enteral nutrition (EN) practices in intensive care unit (ICU) patients with circulatory shock is limited. We hypothesized early EN (EEN), as compared to delayed EN (DEN), is associated with improved clinical outcomes in mechanically ventilated (MV) patients with circulatory shock. METHODS: We analyzed a dataset from an international, multicenter, pragmatic randomized clinical trial (RCT) evaluating protein dose in ICU patients. Data were collected from ICU admission, and EEN was defined as initiating < 48 h from ICU admission and DEN > 48 h. We identified MV patients in circulatory shock to evaluate the association between the timing of EN initiation and clinical outcomes. The regression analysis model controlled for age, mNUTRIC score, APACHE II score, sepsis, and Site. RESULTS: We included 626 patients, from 52 ICUs in 14 countries. Median age was 60 years [18-93], 55% had septic shock, 99% received norepinephrine alone, 91% received EN alone, and 50.3% were randomized to a usual protein dose. Forty-two percent of EEN patients had persistent organ dysfunction syndrome plus death at day 28, compared to 53% in the DEN group (p = 0.04). EEN was associated with more ICU-free days (9.3 ± 9.2 vs. 5.7 ± 7.9, p = 0.0002), more days alive and free of vasopressors (7.1 ± 3.1 vs. 6.3 ± 3.2, p = 0.007), and shorter duration of MV among survivors (9.8 ± 10.9 vs. 13.8 ± 14.5, p = 0.0002). This trend was no longer observed in the adjusted analysis. There were no differences in ICU/60-day mortality or feeding intolerance rates between groups. CONCLUSION: In MV patients with circulatory shock, EEN, as compared to DEN, was associated with improved clinical outcomes, but no longer when adjusting for illness severity. RCTs comparing the efficacy of EEN to DEN in MV patients with circulatory shock are warranted.

Incidence, Risk Factors, and Clinical Consequence of Enteral Feeding Intolerance in the Mechanically Ventilated Critically Ill: An Analysis of a Multicenter, Multiyear Database.

OBJECTIVES: To determine the incidence of enteral feed intolerance, identify factors associated with enteral feed intolerance, and assess the relationship between enteral feed intolerance and key nutritional and clinical outcomes in critically ill patients. DESIGN: Analysis of International Nutrition Survey database collected prospectively from 2007 to 2014. SETTING: Seven-hundred eighty-five ICUs from around the world. PATIENTS: Mechanically ventilated adults with ICU stay greater than or equal to 72 hours and received enteral nutrition during the first 12 ICU days. INTERVENTIONS: None. MEASUREMENT AND MAIN RESULTS: We defined enteral feed intolerance as interrupted feeding due to one of the following reasons: high gastric residual volumes, increased abdominal girth, distension, subjective discomfort, emesis, or diarrhea. The current analysis included 15,918 patients. Of these, 4,036 (24%) had at least one episode of enteral feed intolerance. The enteral feed intolerance rate increased from 1% on day 1 to 6% on days 4 and 5 and declined daily thereafter. After controlling for site and patient covariates, burn (odds ratio 1.46; 95% CIs, 1.07-1.99), gastrointestinal (odds ratio 1.45; 95% CI, 1.27-1.66), and sepsis (odds ratio 1.34; 95% CI, 1.17-1.54) admission diagnoses were more likely to develop enteral feed intolerance, as compared to patients with respiratory-related admission diagnosis. enteral feed intolerance patients received about 10% less enteral nutrition intake, as compared to patients without enteral feed intolerance after controlling for important covariates including severity of illness. Enteral feed intolerance patients had fewer ventilator-free days and longer ICU length of stay time to discharge alive (all p < 0.0001). The daily mortality hazard rate increased by a factor of 1.5 (1.4-1.6; p < 0.0001) once enteral feed intolerance occurred. CONCLUSIONS: Enteral feed intolerance occurs frequently during enteral nutrition delivery in the critically ill. Burn and gastrointestinal patients had the highest risk of developing enteral feed intolerance. Enteral feed intolerance is associated with lower enteral nutrition delivery and worse clinical outcomes. Identification, prevention, and optimal management of enteral feed intolerance may improve nutrition delivery and clinical outcomes in important "at risk" populations.

Enteral nutrition in circulatory shock: friend or foe?

PURPOSE OF REVIEW: Circulatory shock is associated with reduced splanchnic blood flow and impaired gut epithelial barrier function (EBF). Early enteral nutrition (EN) has been shown in animal models to preserve EBF. There are limited human data informing early EN in circulatory shock and critical care nutrition guidelines provide disparate recommendations regarding the optimal timing and dose. The purpose of this review is to describe the harms and benefits of early EN in circulatory shock by identifying and appraising recent human data. RECENT FINDINGS: The cumulative risk of nonocclusive bowel ischemia and necrosis in patients with circulatory shock is no higher than 0.3% across observational and randomized controlled trial-level data, and whether the risk is increased by EN delivery remains uncertain. Observational data suggest that early EN in circulatory shock is associated with improved clinical outcomes but data from robust randomized controlled trials remain equivocal, so the optimal timing and dose remain unknown. SUMMARY: Based on the best available data, initiating restrictive dose EN into the stomach after initial resuscitation in patients with circulatory shock does not appear to be harmful. In fact, early EN may preserve EBF and improve clinical outcomes.

The effect of higher versus lower protein delivery in critically ill patients: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: The optimal protein dose in critical illness is unknown. We aim to conduct a systematic review of randomized controlled trials (RCTs) to compare the effect of higher versus lower protein delivery (with similar energy delivery between groups) on clinical and patient-centered outcomes in critically ill patients. METHODS: We searched MEDLINE, EMBASE, CENTRAL and CINAHL from database inception through April 1, 2021.We included RCTs of (1) adult (age ≥ 18) critically ill patients that (2) compared higher vs lower protein with (3) similar energy intake between groups, and (4) reported clinical and/or patient-centered outcomes. We excluded studies on immunonutrition. Two authors screened and conducted quality assessment independently and in duplicate. Random-effect meta-analyses were conducted to estimate the pooled risk ratio (dichotomized outcomes) or mean difference (continuous outcomes). RESULTS: Nineteen RCTs were included (n = 1731). Sixteen studies used primarily the enteral route to deliver protein. Intervention was started within 72 h of ICU admission in sixteen studies. The intervention lasted between 3 and 28 days. In 11 studies that reported weight-based nutrition delivery, the pooled mean protein and energy received in higher and lower protein groups were 1.31 ± 0.48 vs 0.90 ± 0.30 g/kg and 19.9 ± 6.9 versus 20.1 ± 7.1 kcal/kg, respectively. Higher vs lower protein did not significantly affect overall mortality [risk ratio 0.91, 95% confidence interval (CI) 0.75-1.10, p = 0.34] or other clinical or patient-centered outcomes. In 5 small studies, higher protein significantly attenuated muscle loss (MD -3.44% per week, 95% CI -4.99 to -1.90; p < 0.0001). CONCLUSION: In critically ill patients, a higher daily protein delivery was not associated with any improvement in clinical or patient-centered outcomes. Larger, and more definitive RCTs are needed to confirm the effect of muscle loss attenuation associated with higher protein delivery. PROSPERO registration number: CRD42021237530.

Fiber in the ICU: Should it Be a Regular Part of Feeding?

PURPOSE OF REVIEW: To highlight the controversy of fiber use in the current critical care nutrition guidelines; review the effect of fiber on the gut microbiota in the critically ill; and examine the data on fiber and outcomes in the intensive care setting. RECENT FINDINGS: Fiber is increasingly recognized as a necessary component of colonic health and nutrition support. In critical illness there is a shift toward gut dysbiosis and immune dysregulation. Through fermentation and the generation of short-chain fatty acids, fiber has a role in maintaining intestinal homeostasis, immune function, and supporting commensal bacteria. In contrast to fermentable fiber, recent animal models suggest that non-fermentable fiber can also favorably alter intestinal homeostasis in a mechanism distinct from short chain fatty acids. In the critically ill, RCTs and meta-analyses suggest that soluble and mixed fiber supplemented enteral nutrition can reduce diarrhea and is well tolerated. Based on limited data, there may be benefits in reducing length of hospital stay, certain infections, and glucose metabolism. Nonetheless, the role of fiber enriched nutrition in critically ill patients is controversial as evident in the conflicting guidelines. Despite shortcomings in the literature, soluble and mixed fiber supplemented enteral nutrition is safe and beneficial in most hemodynamically stable intensive care patients. More research is necessary to determine optimal fiber composition.

When Pandemics Collide: the Interplay of Obesity and COVID-19.

PURPOSE OF REVIEW: The COVID-19 pandemic has been associated with significant morbidity and mortality worldwide. In addition to those with advanced age and co-morbidities such as heart disease or cancer, obese individuals have also had very high rates of hospitalization, critical illness, need for ventilator support, as well as mortality. A number of factors associated with obesity have led to devastating consequences as these two pandemics have interacted. RECENT FINDINGS: Obese individuals through a combination of structural and cellular level changes have greater risk of ischemic heart disease, diabetes, cancer, and respiratory disease, which are themselves risk-factors for acquiring COVID-19 disease. These structural changes also result in increased intra-abdominal and intra-thoracic pressure as well as a restrictive lung physiology that leads to reduction in total lung capacity, functional residual capacity, and increase in airway hyper-reactivity. Adipose tissue is also impacted in obese individuals leading to local as well as systemic inflammation, which can contribute to increased release of free fatty acids and systemic insulin resistance. Additionally, angiotensin-converting enzyme 2 and dipeptidyl peptidase 4, which act as receptors for SARS-CoV-2 are also significantly increased in obese individuals. The present manuscript reviews these structural, immune, and molecular changes associated with obesity that make obese individuals more vulnerable to acquiring severe COVID-19 and more challenging to manage associated complications.

Intermittent versus continuous feeding in critically ill adults.

PURPOSE OF REVIEW: Early enteral nutrition is recommended in critically ill adult patients. The optimal method of administering enteral nutrition remains unknown. Continuous enteral nutrition administration in critically ill patients remains the most common practice worldwide; however, its practice has recently been called into question in favor of intermittent enteral nutrition administration, where volume is infused multiple times per day. This review will outline the key differences between continuous and intermittent enteral nutrition, describe the metabolic responses to continuous and intermittent enteral nutrition administration and outline recent studies comparing continuous with intermittent enteral nutrition administration on outcomes in critically ill adults. RECENT FINDINGS: In separate studies, healthy humans and critically ill patients receiving intermittent nutrition (infused over 3 h) had improved whole body protein balance from negative to positive. These studies did not have an isonitrogenous control group. A randomized controlled trial of intermittent bolus versus continuous enteral nutrition in healthy humans found that intermittent bolus feeding increased mesenteric arterial blood flow, increased insulin and peptide YY and reduced blood glucose concentration. A randomized controlled trial comparing intermittent bolus to continuous enteral nutrition in critically ill patients did not demonstrate clinically relevant differences in glycemic variability, insulin use or tube feeding volume or caloric intake between the two groups. SUMMARY: Studies in healthy humans suggest that intermittent nutrient administration, as opposed to continuous, improves whole body protein synthesis. Unfortunately, similarly designed studies are lacking for critically ill patients. Future studies evaluating the impact of intermittent versus continuous nutrition administration on critical care outcomes should take into account factors such as protein quantity, protein quality and delivery route (enteral and/or parenteral). Until further studies are conducted in critically ill patients, a recommendation for or against intermittent nutrition delivery cannot be made.

Should fecal microbial transplantation be used in the ICU?

PURPOSE OF REVIEW: Maintaining gut barrier defenses, modulating immune responses, and supporting the role of commensal microbiota are major factors influencing outcome in critical illness. Of these, maintaining a commensal 'lifestyle' and preventing the emergence of a virulent pathobiome may be most important in reducing risk of infection and multiple organ failure. RECENT FINDINGS: The polymeric formulas utilized for enteral nutrition in the ICU are absorbed high in the gastrointestinal tract and may not reach the microbial burden in the cecum where their effect is most needed. The provision of a few select probiotic organisms may be insufficient to refaunate the gut and establish a 'recovery pattern,' propelling the patient toward health and homeostasis. Use of fecal microbial transplantation (FMT) appears to be a more successful strategy for replenishing the intestinal microbiome and maintaining its commensal phenotypic expression. SUMMARY: FMT has become an attractive option to mitigate multiple organ dysfunction in the ICU. This article discusses the physiology, rationale, early experience, and expectations for such therapy in the critically ill patient.

Can Specialized Pro-resolving Mediators Deliver Benefit Originally Expected from Fish Oil?

PURPOSE OF THE REVIEW: Fish oil (FO) supplementation has historically been used by individuals suffering from cardiovascular disease and other inflammatory processes. However, a meta-analysis of several large randomized control trials (RCTs) suggested FO conferred no benefit in reducing cardiovascular risk. Skeptics surmised that the lack of benefit was related to FO dose or drug interactions; therefore, the widely accepted practice of FO consumption was brought into question. RECENT FINDINGS: Thereafter, Serhan et al. identified specialized pro-resolving mediators (SPMs) to be one of the bioactive components and mechanisms of action of FO. SPMs are thought to enhance resolution of inflammation, as opposed to classic anti-inflammatory agents which inhibit inflammatory pathways. Numerous diseases, including persistent Inflammation, immunosuppression, and catabolic syndrome (PICS), are rooted in a burden of chronic inflammation. SPMs are gaining traction as potential therapeutic agents used to resolve inflammation in cardiovascular disorders, inflammatory bowel disease, sepsis, pancreatitis, and acute respiratory distress syndrome (ARDS). This narrative reviews the history of FO and the various studies that made the health benefits of FO inconclusive, as well as an overview of SPMs and their use in specific disease states.