Considerations for medical nutrition therapy management of the critically ill patient with hematological malignancies: A narrative review.

Patients with hematological malignancies (HMs) are more frequently admitted now than in the past to the intensive care unit (ICU) due to more aggressive approaches in primary therapy of HMs and the need for critical care support. Pathophysiological alterations derived from HMs and the different hematological therapies, such as chemotherapy, negatively affect gastrointestinal (GI) function, metabolism, and nutrition status. Further, malnutrition strongly influences outcomes and tolerance of the different hematological therapies. In consequence, these critically ill patients frequently present with malnutrition and pathophysiological alterations that create challenges for the delivery of medical nutrition therapy (MNT) in the ICU. Frequent screening, gauging tolerance, and monitoring nutrition status are mandatory to provide individualized MNT and achieve nutrition objectives. The present review discusses how HM impact GI function and nutrition status, the importance of MNT in patients with HM, and specific considerations for guidance in providing adequate MNT to these patients when admitted to the ICU.

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.

Browning of white adipose tissue may be an appropriate adaptive response to critical illness.

Both the baseline amount of brown adipose tissue (BAT) and the capacity to stimulate browning of white adipose tissue (WAT) may provide a protective effect to the patient in a critical care setting. Critical illness is associated with reduced mitochondrial volume and function resulting in the increased production of reactive oxygen species, greater demand for adenosine triphosphate, a switch to uncoupled fat metabolism, and hibernation of the organelle, which all contribute to multiple organ failure. Increasing insulin resistance, decreasing fatty acid oxidation, and dependence on carbohydrate metabolism result. Browning of WAT may oppose many of these adverse effects. The presence of BAT and the changes associated with browning may help dissipate oxidative stress, increase consumption and utilization of metabolites, and reduce pro-inflammatory actions. The number of mitochondria increases, and there is greater infiltration of macrophages into adipose tissue. A shift occurs in macrophage expression from the M1 to M2 phenotype, an effect which further dampens inflammation, increases insulin sensitivity, and improves tissue healing and remodeling. Any benefit from these responses may be lost in the disease states of chronic hypermetabolism (such as burns or cancer cachexia) in which the persistence of these physiologic effects may become detrimental, contributing to excessive weight loss, adipose wasting, and loss of lean body mass. This paper discusses the plasticity of adipose tissue and whether shifts in its physiology provide clinical advantages in the intensive care unit.

The importance of providing dietary fiber in medical and surgical critical care.

The early provision of soluble/insoluble fiber to the patient who is critically ill has been controversial in the past. Especially in the setting of hemodynamic instability, dysmotility, or impaired gastrointestinal transit, fear of inspissation of formula with precipitation of nonocclusive mesenteric ischemia (NOMI)/nonocclusive bowel necrosis (NOBN) limited its utilization by medical and surgical intensivists. The incidence of NOMI/NOBN has been estimated at 0.2%-0.3% for all intensive care unit (ICU) patients receiving enteral nutrition (EN), and the occurrence of inspissated formula is even less. The science supporting a benefit from providing fiber has recently increased exponentially. The fermentation of soluble fibers leading to the production of short chain fatty acids supports gut barrier function, modulates immune responses, and promotes refaunation of commensal organisms. The "butyrate effect" refers to local (gastrointestinal tract) and systemic anti-inflammatory responses mediated by the M2 polarization of macrophages, inhibition of histone deacetylase, and stimulation of ubiquitous G protein receptors. Both soluble and insoluble fiber have been shown to promote intestinal motility, reduce feeding intolerance, and shorten hospital length of stay. The benefit of providing dietary fiber early upon admission to the ICU outweighs its minimal associated risk. The point at which the intensivist determines that is safe to initiate EN, both soluble and insoluble fiber should be included in the enteral formulation.

Personalized nutrition therapy in critical care: 10 expert recommendations.

Personalization of ICU nutrition is essential to future of critical care. Recommendations from American/European guidelines and practice suggestions incorporating recent literature are presented. Low-dose enteral nutrition (EN) or parenteral nutrition (PN) can be started within 48 h of admission. While EN is preferred route of delivery, new data highlight PN can be given safely without increased risk; thus, when early EN is not feasible, provision of isocaloric PN is effective and results in similar outcomes. Indirect calorimetry (IC) measurement of energy expenditure (EE) is recommended by both European/American guidelines after stabilization post-ICU admission. Below-measured EE (~ 70%) targets should be used during early phase and increased to match EE later in stay. Low-dose protein delivery can be used early (~ D1-2) (< 0.8 g/kg/d) and progressed to ≥ 1.2 g/kg/d as patients stabilize, with consideration of avoiding higher protein in unstable patients and in acute kidney injury not on CRRT. Intermittent-feeding schedules hold promise for further research. Clinicians must be aware of delivered energy/protein and what percentage of targets delivered nutrition represents. Computerized nutrition monitoring systems/platforms have become widely available. In patients at risk of micronutrient/vitamin losses (i.e., CRRT), evaluation of micronutrient levels should be considered post-ICU days 5-7 with repletion of deficiencies where indicated. In future, we hope use of muscle monitors such as ultrasound, CT scan, and/or BIA will be utilized to assess nutrition risk and monitor response to nutrition. Use of specialized anabolic nutrients such as HMB, creatine, and leucine to improve strength/muscle mass is promising in other populations and deserves future study. In post-ICU setting, continued use of IC measurement and other muscle measures should be considered to guide nutrition. Research on using rehabilitation interventions such as cardiopulmonary exercise testing (CPET) to guide post-ICU exercise/rehabilitation prescription and using anabolic agents such as testosterone/oxandrolone to promote post-ICU recovery is needed.

Nutrition dose in the early acute phase of critical illness: Finding the sweet spot and heeding the lessons from the NUTRIREA trials.

The landmark NUTRIREA-2 and NUTRIREA-3 trials compared the route and dose of nutrition, respectively, in critically ill patients with circulatory shock. The results of both trials support a "less-is-more" paradigm shift in the early acute phase of critical illness. In this review, the authors outline and appraise the results of the NUTRIREA-2 and NUTRIREA-3 trials, introduce the concept of identifying the "sweet spot" for nutrition dose based on severity of illness/nutrition risk and nutrition dose, and identify the unintended consequences of delivering full-dose nutrition in sicker critically ill patients during the early acute phase of critical illness.

Immunonutrition vs standard nutrition for patients with cancer.

The prevailing belief in the value of immunonnutrition has been questioned as different patient populations show variable responses ranging from no benefit or even harm to significant improvements in clinical outcomes. The subject of this invited review is a previously published meta-analysis that showed important benefits from the perioperative use of an immunonutrition formula (defined as nutrition therapy that contains specific immune-modulating agents) in a distinct population: adult patients with cancer undergoing an elective major surgical operation. Findings showed that use of an immunonutrition formula was associated with reduced infectious morbidity, anastomotic leakage, hospital length of stay, and postoperative complications compared with standard formulations. These benefits were seen after adjusting for bias and removal of older publications. Issues, such as dosing, duration of therapy, baseline nutrition status, content of specific immunomodulatory agents, and route of delivery that contributed to the beneficial response, were discussed. Little difference in response was seen between well-nourished and malnourished patients, but geographic differences were seen, with greater outcome benefits seen in studies originating from Europe than from Asia or the United States. The best results were seen when at least three agents (arginine, fish oil, and RNA nucleotides) were given, with the timing of the delivery occurring throughout the perioperative period. A review of this meta-analysis is warranted because it shows a consistent benefit from such therapy over 30 years of clinical research, provides a detailed subset analysis of related issues, and highlights its value in improving outcome in this patient population.

Surgical Diagnoses of Pancreatic Adenocarcinoma Not Found on Previous Endoscopic Ultrasound: A Case Series and Review of the Literature.

INTRODUCTION: Pancreatic cancer is a leading cause of death in North America and Western Europe with rising rates in the developing world. Endoscopic ultrasound (EUS) with FNA (fine needle aspiration) is a critical component in the evaluation and diagnosis of pancreatic lesions with a high sensitivity and specificity. In this paper, we report patients at our center who eventually developed pancreatic cancer despite an early negative EUS, and identifying factors that may result in a missed diagnosis. METHODS: The University of Louisville database was queried for patients who had a Whipple procedure for presumed benign disease and had a pre-operative EUS between 2008 and 2018. Patients who had pancreatic adenocarcinoma on final pathology were identified. Demographic, clinical, EUS, operative, and pathologic details were reviewed for each case in efforts to identify factors associated with failure to diagnose a pancreatic malignancy on EUS. RESULTS: Five patients who had pancreatic adenocarcinoma on final pathology were reviewed in detail and their cases are presented in the paper. Four of the patients had dilation of the common bile duct, three had chronic pancreatitis. Two of them had previous surgery on the pancreas or bile ducts. CONCLUSIONS: All of the patients presented in the paper had variables that made their EUS evaluation challenging. A high index of suspicion must be maintained in patients that do not improve after appropriate treatment of their strictures or pancreatic lesions. In the future, new techniques, such as fine needle biopsy and biomarker assays, may improve diagnosis accuracy.

2022 Peggi Guenter Excellence in Clinical Practice Lectureship: Expanding the clinical practice of nutrition-Challenging the known, exposing inconvenient truths, and engaging the young.

To expand the clinical practice of nutrition, the influence of the American Society for Parenteral and Enteral Nutrition (ASPEN) must reach an audience outside the nutrition community, must be relevant and meaningful to clinicians, and must meet the needs of specific patient populations throughout medical and surgical specialties. Individual members of our society need to share their enthusiasm and expertise with youth through conscious, intentional mentorship. Efforts should be made to promote advanced practice, increasing the skill set of the individual nutritionist. Nutrition research should be of the highest quality, matching that of any current medical or surgical discipline. Members of a nutrition consult service should speak the same language as the physicians they work with, through discussions on rounds and in communication through their charting and consult notes. Our societal guidelines should define clinical practice. Relationships with other societies should be cultivated through these guidelines, position papers, and public health initiatives to increase the relevance and impact of our society. To position itself for future generations, the role of ASPEN should be expanded to be more comprehensive and involve all nutrition aspects of patient care.

Preparative Fasting Orders for Medical/Surgical Interventions and Imaging Studies: Time to Review and Revise!

PURPOSE OF THE REVIEW: Preparative fasting orders arose out of a purported need to enhance imaging studies, reduce interference of food with intended medical/surgical interventions, and protect the patient from vomiting and aspiration pneumonia. This review discusses the frequency, appropriateness, and efficacy of fasting orders in meeting those needs and whether their use should be modified in the future. RECENT FINDINGS: Nil per os (NPO) orders are overused, as they are often inappropriate, typically excessive, and routinely create barriers which may increase risk for patients. Fasting orders are used more often for medical procedures than for surgical operations or imaging studies. One fourth of NPO orders are inappropriate, and the intended procedure or study is canceled 20% of the time usually for a change in plans or scheduling error and rarely because of patient eating. Nausea/vomiting associated with contrast media or imaging studies is rare, self-limited, and not linked to preparatory fluid or food ingestion. Prolonged fasting reduces patient cooperation and satisfaction, and may contribute to a higher rate of complications. Each institution should review and revise preparative fasting orders. Drinking of fluids should be allowed without restriction. Truncated periods of solid food restriction may be required due to technical reasons related to specific imaging studies, and for procedures or surgical operations which require sedation or general anesthesia. Inappropriate and prolonged fasting should be avoided, as they create barriers to adequate nutritional therapy and impose added risk with regard to patient outcomes.

Optimizing the nutrition support care model: Analysis of survey data.

BACKGROUND: Malnutrition is underrecognized and underdiagnosed, despite high prevalence rates and associated poor clinical outcomes. The involvement of clinical nutrition experts, especially physicians, in the care of high-risk patients with malnutrition remains low despite evidence demonstrating lower complication rates with nutrition support team (NST) management. To facilitate solutions, a survey was designed to elucidate the nature of NSTs and physician involvement and identify needs for novel nutrition support care models. METHODS: This survey assessed demographics of NSTs, factors contributing to the success of NSTs, elements of nutrition education, and other barriers to professional growth. RESULTS: Of 255 respondents, 235 complete surveys were analyzed. The geographic distribution of respondents correlated with population concentrations of the United States (r = 90.8%, p < .0001). Most responding physicians (46/57; 80.7%) reported being a member of NSTs, compared with 56.5% (88/156) of dietitians. Of those not practicing in NSTs (N = 81/235, 34.4%), 12.3% (10/81) reported an NST was previously present at their institution but had been disbanded. Regarding NSTs, financial concerns were common (115/235; 48.9%), followed by leadership (72/235; 30.6%), and healthcare professional (HCP) interest (55/235; 23.4%). A majority (173/235; 73.6%) of all respondents wanted additional training in nutrition but reported insufficient protected time, ability to travel, or support from administrators or other HCPs. CONCLUSION: Core actions resulting from this survey focused on formalizing physician roles, increasing interdisciplinary nutrition support expertise, utilizing cost-effective screening for malnutrition, and implementing intervention protocols. Additional actions included increasing funding for clinical practice, education, and research, all within an expanded portfolio of pragmatic nutrition support care models.

Nutrition, defecation, and the lower gastrointestinal tract during critical illness.

PURPOSE OF REVIEW: The goal of this report is to delineate the correlation between constipation as a manifestation of impaired gastrointestinal transit with adverse clinical outcomes, to identify risk factors, which predispose to this condition, and outline a management scheme for prophylactic treatment. RECENT FINDINGS: Constipation is common in the ICU, affecting upwards of 60-85% of critically ill patients. As suggested by case series and observational studies, constipation may be an independent prognostic factor identifying patients with greater disease severity, higher likelihood of organ dysfunction, longer duration of mechanical ventilation, prolonged hospital length of stay, and possibly reduced survival. Treating constipation is a low priority for intensivists often relegated to the nursing service, and few ICUs have well designed protocols in place for a bowel regimen. Small randomized controlled trials show improvement in certain outcome parameters in response to a daily lactulose therapy; hospital length of stay, sequential organ failure assessment scores, and duration of mechanical ventilation. However, aggregating the data from these studies in two separate meta-analyses showed that the effect of a bowel regimen on these three endpoints were not statistically different. SUMMARY: No causal relationship can be determined between constipation and adverse outcomes. Nonetheless, a clinical correlation seems to exist. Whether constipation is an epiphenomenon or simply a reflection of greater severity of critical illness, at some point it may contribute to worsening morbidity in the ICU. A graded prophylactic bowel regimen should help reverse impairment of the gastrointestinal transit and aid in reducing its deleterious impact on the hospital course of the critically ill patient.

Barriers to nutrition therapy in the critically ill patient with COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has created challenges for intensivists, as high ventilatory demands and prolonged hypermetabolism make it difficult to sustain nutrition status. The purpose of this survey was to determine current practices in nutrition therapy and identify barriers to its delivery. METHODS: A survey about delivering nutrition therapy to critically ill patients with COVID-19 was sent to clinicians at academic and community hospitals from September to December 2020. RESULTS: Of 440 who viewed the survey, 199 (45%) completed the questionnaire. Respondents were composed of 30%, physicians and 70% registered dietitians, with 51% representing community programs, 43% academic institutions, and 6% Veterans Affairs centers. Half (49%) had protocols for managing critically ill patients with COVID-19, and 21% had a protocol for nutrition therapy. Although most respondents (83%) attempted to feed by the intragastric route, only 9% indicated that energy/protein needs were met. The biggest barriers to delivery of enteral nutrition (EN) involved the patients unpredictable clinical course and fear of aspiration given the lack of respiratory reserve. Intensivists were reluctant to add supplemental parenteral nutrition (PN) because of perceived lack of benefit. CONCLUSION: The survey results would suggest that strategies for nutrition therapy based on the intragastric infusion of EN are unsuccessful in meeting the energy/protein needs of critically ill patients with COVID-19. It is likely these barriers exist in providing nutrition to non-Covid-19 critically ill patients. Intensivists need protocols that optimally deliver intragastric EN, consider early postpyloric infusion, and address adding supplemental PN in a deteriorating nutrition status.

Prolonged progressive hypermetabolism during COVID-19 hospitalization undetected by common predictive energy equations.

BACKGROUND & AIMS: Indirect calorimetry (IC) is the gold-standard for determining measured resting energy expenditure (mREE) in critical illness. When IC is not available, predicted resting energy expenditure (pREE) equations are commonly utilized, which often inaccurately predict metabolic demands leading to over- or under-feeding. This study aims to longitudinally assess mREE via IC in critically ill patients with SARS-CoV-2 (COVID-19) infection throughout the entirety of, often prolonged, intensive care unit (ICU) stays and compare mREE to commonly utilized pREE equations. METHODS: This single-center prospective cohort study of 38 mechanically ventilated COVID-19 patients from April 1, 2020 to February 1, 2021. The Q-NRG® Metabolic Monitor was used to obtain IC data. The Harris-Benedict (HB), Mifflin St-Jeor (MSJ), Penn State University (PSU), and weight-based equations from the American Society of Parenteral and Enteral Nutrition - Society of Critical Care Medicine (ASPEN-SCCM) Clinical Guidelines were utilized to assess the accuracy of common pREE equations and their ability to predict hypo/hypermetabolism in COVID-19 ICU patients. RESULTS: The IC measures collected revealed a relatively normometabolic or minimally hypermetabolic mREE at 21.3 kcal/kg/d or 110% of predicted by the HB equation over the first week of mechanical ventilation (MV). This progressed to significant and uniquely prolonged hypermetabolism over successive weeks to 28.1 kcal/kg/d or 143% of HB predicted by MV week 3, with hypermetabolism persisting to MV week 7. Obese individuals displayed a more truncated response with significantly lower mREE versus non-obese patients in MV week 1 (19.5 ± 1.0 kcal/kg/d vs 25.1 ± 1.8 kcal/kg/d, respectively; p < 0.01), with little change in weeks 2-3 (19.5 ± 1.5 kcal/kg/d vs 28.0 ± 2.0 kcal/kg/d; p < 0.01). Both ASPEN-SCCM upper range and PSU pREE equations provided close approximations of mREE yet, like all pREE equations, occasionally over- and under-predicted energy needs and typically did not predict late hypermetabolism. CONCLUSIONS: Study results show a truly unique metabolic response in COVID-19 ICU patients, characterized by significant and prolonged, progressive hypermetabolism peaking at 3 weeks' post-intubation, persisting for up to 7 weeks in ICU. This pattern was more clearly demonstrated in non-obese versus obese patients. This response is unique and distinct from any previously described model of ICU stress response in its prolonged hypermetabolic nature. This data reaffirms the need for routine, longitudinal IC measures to provide accurate energy targets in COVID-19 ICU patients. The PSU and ASPEN-SCCM equations appear to yield the most reasonable estimation to IC-derived mREE in COVID-19 ICU patients, yet still often over-/under-predict energy needs. These findings provide a practical guide for caloric prescription in COVID-19 ICU patients in the absence of IC.

Food Access, Food Insecurity, and Gun Violence: Examining a Complex Relationship.

PURPOSE OF REVIEW: Food insecurity and gun violence are timely and relevant public health issues impacting many regions within the USA with a potential association. Terminology surrounding food access and food security can be confusing, which is important to understand when examining the relationship between these issues and gun violence. RECENT FINDINGS: Food insecurity is an individual level risk factor that appears to correlate with an increased rate of exposure and future involvement in violence. Food deserts represent geographic regions with limited access to food but do not necessarily represent regions with high prevalence of food insecurity. Although both food insecurity and food deserts in urban regions have been linked with increased incidence of gun violence, a high prevalence of food insecurity was found to be more predictive. A high prevalence of food insecurity in urban regions likely serves as a marker for socioeconomic disadvantage and intentional disinvestment. These regions are predictably associated with a higher incidence of interpersonal gun violence. Food deserts in rural areas have not, to date, been shown to correlate with interpersonal gun violence. Urban food insecurity and gun violence are both likely the byproduct of structural violence. Despite the significant overlap and similar contributors, the application of the public health framework in addressing these two issues has historically been quite different.

How Differences in the Disease Process of the COVID-19 Pandemic Pose Challenges to the Delivery of Critical Care Nutrition.

PURPOSE OF REVIEW: The COVID-19 pandemic is a unique disease process that has caused unprecedented challenges for intensive care specialists. The hyperinflammatory hypermetabolic nature of the disease and the complexity of its management create barriers to the delivery of nutritional therapy. This review identifies the key differences which characterize this pandemic from other disease processes in critical illness and discusses alternative strategies to enhance success of nutritional support. RECENT FINDINGS: Prolonged hyperinflammation, unlike any previously described pattern of response to injury, causes metabolic perturbations and deterioration of nutritional status. High ventilatory demands, hypercoagulation with the risk of bowel ischemia, and threat of aspiration in patients with little or no pulmonary reserve, thwart initial efforts to provide early enteral nutrition (EN). The obesity paradox is invalidated, tolerance of EN is limited, intensivists are reluctant to add supplemental parenteral nutrition (PN), and efforts to give sufficient nutritional therapy remain a low priority. The nature of the disease and difficulties providing traditional critical care nutrition lead to dramatic deterioration of nutritional status. Institutions should not rely on insufficient gastric feeding alone but focus instead on redoubling efforts to provide postpyloric deep duodenal/jejunal EN or re-examine the role of supplemental PN in this population of patients with such severe critical illness.

Can feeding strategies alter immune signaling and gut sepsis in critical illness?

The insult necessitating admission to the intensive care unit propels the patient along a course involving increasing oxidative stress, immune dysregulation, and adverse outcomes. As the largest immune organ with the greatest microbial burden, the gastrointestinal (GI) tract may change the speed and direction the patient follows along this pathway. The gut's influence is mediated by a complex process of cross-talk immune signaling between the intestinal epithelium, the liver, and the microbiome. Agents that invoke this response vary from mitochondrial DNA, inflammatory cytokines, and bacterial organisms to short-chain fatty acids and bile salts. The site of action of these agents again varies widely from pattern-recognition receptors, G protein receptors, and farnesoid X receptors in the gut and liver to transcriptional factors in epithelial cells, hepatocytes, macrophages, and neutrophils. Whereas the initial focus of response may be local within the GI tract and liver, the process extends in a systemic manner to affect immune tissue and various organs at distant sites. The gut can modulate this cross-talk signaling through numerous strategies in the design of nutrition therapy. The physiologic response to luminal nutrients and short-chain fatty acids, and more novel approaches like using phosphorylated polyethylene glycol, bovine serum-derived immunoglobulin, and specialized proresolving molecules, may help slow disease progression and even reverse the patient's course toward one of health and recovery. The optimal benefit to be derived from nutrition therapy may have more to do with the degree to which immune cross-talk signaling can be modified by such innovative strategies.