Enteral versus parenteral feeding. Effects on septic morbidity after blunt and penetrating abdominal trauma

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

BACKGROUND AND PURPOSE

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 and published in the Journal of JSICM, [2017; Volume 24 (supplement 2)] 10.3918/jsicm.24S0001 and Journal of Japanese Association for Acute Medicine [2017; Volume 28, (supplement 1)] http://onlinelibrary.wiley.com/doi/10.1002/jja2.2017.28.issue-S1/issuetoc.This abridged English edition of the J-SSCG 2016 was produced with permission from the Japanese Association of Acute Medicine and the Japanese Society for Intensive Care Medicine.

METHODS

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ) and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (> 66.6%) majority vote of each of the 19 committee members.

RESULTS

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation, and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty-seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for five CQs.

CONCLUSIONS

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

Barriers and Solutions to Delivery of Intensive Care Unit Nutrition Therapy

Despite recommendations for early enteral nutrition (EN) in critically ill patients, numerous factors contribute to incomplete delivery of EN, including insufficient nutrition risk screening in critically ill patients, underutilization of enteral feeding protocols, fixed rate-based enteral infusion targets with frequent EN interruption, and suboptimal provider practices regarding nutrition support therapy. The purpose of this narrative review is to identify common barriers to optimizing and delivering nutrition in critically ill patients, and suggest strategies and solutions to overcome barriers.

Enteral Nutrients and Gastrointestinal Physiology

The gastrointestinal (GI) tract is a highly efficient organ system with specialized structures to facilitate digestion and absorption of nutrients to meet the body's needs. The presence of nutrients in the GI tract supports optimal structure and function, stimulates regulatory hormones, and supports the microbiota, the population of microorganisms residing in the GI tract. A lack of enteral nutrition (EN) results in impaired GI integrity and serious patient complications, making EN a priority. Normal GI physiology is reviewed, and the regulatory impact of luminal nutrients on GI function is discussed.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

Background and Purpose

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 in Japanese. An English-language version of these guidelines was created based on the contents of the original Japanese-language version.

Methods

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ), and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (>66.6%) majority vote of each of the 19 committee members.

Results

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for 5 CQs.

Conclusions

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

Surgical Critical Care: Gastrointestinal Complications

Critical illness and injury affect the gastrointestinal tract almost uniformly. Complications include the sequelae of direct intestinal injury and repair, impaired motility, intra-abdominal hypertension, and ulceration, among others. Contemporary clinical practice has incorporated many advances in the prevention and treatment of gastrointestinal complications during critical illness. This article discusses the epidemiology, risk factors, means of diagnosis, treatment, and prevention of some of these compilations.

Septic predictor index: A novel platform to identify thermally injured patients susceptible to sepsis

BACKGROUND

During the past decades' sepsis has become the major cause of death in severely burned patients. Despite the importance of burn sepsis, its diagnosis, let alone its prediction, is difficult if not impossible. Recently, we have demonstrated burn patients have increased NLRP3 inflammasome activation in white adipose tissue. We aimed to delineate a unique immune profile that can be used to identify septic outcomes in severely burned patients.

METHODS

Adult burn patients (n = 37) admitted to our burn center between June 2013-2015 were enrolled in this study. White adipose tissue from the site of injury and plasma were collected from severely burned patients (>20% total body surface area) within 96 hours after thermal injury, indiscriminate of sex or age.

RESULTS

We found that patients exhibiting aberrantly high levels of proinflammatory interleukin-1β and decreased macrophages at the site of injury are highly susceptible to development of sepsis. Septic patients also had increased anti-inflammatory (interleukin-10, interleukin-1RA) cytokines in plasma. The Septic Predictor Index was generated as a quotient for the site of injury macrophage proportion and interleukin-1β production. All patients who eventually develop sepsis had septic predictor index values >0.5. Septic patients with Septic Predictor Index values >1 all had sepsis onset within 12 days post-injury, whereas patients with Septic Predictor Index values between 0.5-1 all had later onset (>12 days).

CONCLUSION

The Septic Predictor Index can determine sepsis onset accurately in thermally injured patients a priori and further enables surgeons to develop clinical studies and focused therapies specifically designed for septic cohorts.

Effects of semielemental diet containing whey peptides on Peyer's patch lymphocyte number, immunoglobulin A levels, and intestinal morphology in mice

BACKGROUND

Enteral nutrition (EN) is the gold standard of nutritional therapy for critically ill or severely injured patients, because EN promotes gut and hepatic immunity, thereby preventing infectious complications as compared with parenteral nutrition. However, there are many EN formulas with different protein and fat contents. Their effects on gut-associated lymphoid tissue remain unclear. Recently, semielemental diets (SEDs) containing whey peptides as a nitrogen source have been found to be beneficial in patients with malabsorption or pancreatitis. Herein, we examined the influences of various dietary formulations on gut immunity to clarify the advantages of SEDs over elemental diets.

METHODS

Forty-four male Institute of Cancer Research mice were randomized to four groups: chow (CH: n = 5), intragastric total parenteral nutrition (IG-TPN: n = 13), elemental diet (ED: n = 13), and SED (n = 13). The CH group received CH diet ad libitum, whereas the IG-TPN, ED (Elental, Ajinomoto, Japan), and SED (Peptino, Terumo, Japan) groups were given their respective diets for 5 day via gastrostomy. After 5 days, the mice were killed to obtain whole small intestines. Peyer's patch (PP) lymphocytes were harvested and counted. Their subpopulations were evaluated by flow cytometry. Immunoglobulin A (IgA) levels in intestinal and respiratory tract washings were measured with enzyme-linked immunosorbent assay. Villous height (VH) and crypt depth in the distal intestine were measured by light microscopy.

RESULTS

SED increased the PP cell number and intestinal or respiratory IgA levels to those of CH mice, while ED partially restored these parameters. The IG-TPN group showed the lowest PP cell number and IgA levels among the four groups. VH was significantly greater in the CH than in the other groups. VH in the ED and SED groups also exceeded in the IG-TPN group, while being similar in these two groups. No significant crypt depth differences were observed among the four groups.

CONCLUSIONS

SED administration can be recommended for patients unable tolerate complex enteral diets or a normal diet in terms of not only absorption and tolerability but also maintenance of gut immunity.

Metabolic programming of the epigenome: host and gut microbial metabolite interactions with host chromatin

The mammalian gut microbiota has been linked to host developmental, immunologic, and metabolic outcomes. This collection of trillions of microbes inhabits the gut and produces a myriad of metabolites, which are measurable in host circulation and contribute to the pathogenesis of human diseases. The link between endogenous metabolite availability and chromatin regulation is a well-established and active area of investigation; however, whether microbial metabolites can elicit similar effects is less understood. In this review, we focus on seminal and recent research that establishes chromatin regulatory roles for both endogenous and microbial metabolites. We also highlight key physiologic and disease settings where microbial metabolite-host chromatin interactions have been established and/or may be pertinent.

Critical Care Nutrition: Where's the Evidence?

The surgical critically ill patient is subject to a variable and complex metabolic response, which has detrimental effects on immunity, wound healing, and preservation of lean body muscle. The concept of nutrition support has evolved into nutrition therapy, whereby the primary objectives are to prevent oxidative cell injury, modulate the immune response, and attenuate the metabolic response. This review outlines the metabolic response to critical illness, describes nutritional risk; reviews the evidence for the role, dose, and timing of enteral and parenteral nutrition, and reviews the evidence for immunonutrition in the surgical intensive care unit.

Safety and Efficacy of Electromagnetic-Guided Bedside Placement of Nasoenteral Feeding Tubes versus Standard Placement

Although enteral feeding in critically ill patients has been shown to be beneficial, reliable postpyloric placement of feeding tubes remains a challenge. The standard of care involves blind placement, frequently requiring multiple attempts, and radiographs. To evaluate the effect of electromagnetic-guided bedside placement in reducing time to establishment of feeding, lung placement, use of radiography, and cost, we initiated a prospective trial using electromagnetic-guided bedside placement and compared them to a retrospective cohort. Fifty-three consecutive placements of nasoenteral feeding tubes were made using electromagnetic-guidance on patients requiring enteral nutrition in a surgical intensive care unit at a tertiary care center. Sixty-three placement attempts in the preceding seven months served as controls. There were no significant differences between the two groups in terms of age, sex, weight, body mass index, hiatal or ventral hernias, or previous esophageal/gastric operations. The number of radiographs needed per patient, need for fluoroscopy, radiology charge per patient for the tube placement, and time from first attempt at placement to confirmation of postpyloric location were lower for the electromagnetic-guided group. Use of electromagnetic guidance allows reliable and cost-effective postpyloric enteral feeding tube placement compared with blind insertion.

Effects on nutritional care practice after implementation of a flow chart-based nutrition support protocol in an intensive care unit

Background

Enteral nutrition (EN) is associated with improved outcome in critically ill patients and is more affordable. We compared nutritional care practice in our ICU before and after modification of our nutrition support protocol: Several comprehensive documents were substituted with one flow chart and early EN was encouraged.

Design

Retrospective observational study.

Methods

Nutritional data were collected from admission up to 7 days in 25 patients before and 25 patients after protocol modification.

Results

The percentage of patients receiving EN within 72 hr of admission increased from 64% before to 88% after protocol modification. Cumulative percentage energy from EN during ICU days 1–4 increased from 26–89% of total kcal. Overall amount of nutrition administered enterally increased, with a corresponding marked decline in use of parenteral nutrition. Pre‐modification, >80% of patients received >65% of their calculated nutrition requirements by ICU Day 4; post‐modification this goal was achieved by Day 7.

Feeding Jejunostomy-Associated Small Bowel Necrosis After Elective Esophago-Gastric Resection

BACKGROUND

Feeding jejunostomy has increasingly become a standard adjunctive procedure during major esophago-gastric resections. They provide nutritional support during the post-operative period as required. However, significant early complications have been reported, most notably small bowel necrosis. Literature reports have been restricted to case reports or series. This study aims to determine the frequency of this complication in a cohort of patients undergoing esophago-gastric resection, and identify any difference in the risk of this complication between patients undergoing esophagectomy and gastrectomy.

METHODS

Consecutive patients who had esophago-gastric resections for malignancy and who had a feeding jejunostomy placed were identified from a prospectively maintained database at Leicester Royal Infirmary during the years 2009-2015. Case notes were reviewed to extract information relating to demographics, presenting features and clinical outcome.

RESULTS

The study included 360 patients, 285 of which had esophagectomy and 75 had gastrectomy. There were no small bowel complications among esophagectomy patients (0%), while six patients who had total gastrectomy developed small bowel ischemia or necrosis (8%), p = 0.05, in spite of an identical feeding regimen. Every patient that developed the complication underwent surgery with five out six having resection of the infarcted segment and double-barrel stoma formation. A 6-8-week period of parenteral nutrition was required before stoma reversal. One patient had leucocytosis on the day of diagnosis. The other five patients showed no derangements in biochemical or clinical parameters in the preceding 48 h. Five of the six patients survived.

CONCLUSIONS

Small bowel necrosis and perforation is a life-threatening complication of feeding jejunostomy. In our cohort, it happened exclusively in total gastrectomy patients. Antecedent signs were lacking. The condition requires prompt attention with earlier use of CT scanning and a return to the operating room. The presence of pneumatosis intestinalis on CT scan should prompt surgical intervention that improves survival.

Interleukin-7 Dose-Dependently Restores Parenteral Nutrition–Induced Gut-Associated Lymphoid Tissue Cell Loss but Does Not Improve Intestinal Immunoglobulin A Levels

BACKGROUND

Without enteral nutrition, the mass and function of gut-associated lymphoid tissue (GALT), a center of systemic mucosal immunity, are reduced. Therefore, new therapeutic methods, designed to preserve mucosal immunity during parenteral nutrition (PN), are needed. Our recent study revealed that exogenous interleukin-7 (IL-7; 1 microg/kg twice a day) restores the GALT cell mass lost during intravenous (IV) PN but does not improve secretory immunoglobulin A (IgA) levels. Herein, we studied the IL-7 dose response to determine the optimal IL-7 dose for recovery of GALT mass and function during IV PN. We hypothesized that a high dose of IL-7 would increase intestinal IgA levels, as well as GALT cell numbers.

METHODS

Male mice (n = 42) were randomized to chow, IL-7-0, IL-7-0.1, IL-7-0.33, IL-7-1 and IL-7-3.3 groups and underwent jugular vein catheter insertion. The IL-7 groups were fed a standard PN solution and received IV injections of normal saline (IL-7-0), 0.1, 0.33, 1, or 3.3 microg/kg of IL-7 twice a day. The chow group was fed chow ad libitum. After 5 days of treatment, the entire small intestine was harvested and lymphocytes were isolated from Peyer's patches (PPs), intraepithelial (IE) spaces, and the lamina propria (LP). The lymphocytes were counted and phenotypes determined by flow cytometry (alphabetaTCR, gammadeltaTCR, CD4, CD8, B cell). IgA levels of small intestinal washings were also examined using ELISA (enzyme-linked immunoabsorbent assay).

RESULTS

IL-7 dose-dependently increased total lymphocyte numbers in PPs and the LP. The number of lymphocytes harvested from IE spaces reached a plateau at 1 microg/kg of IL-7. There were no significant differences in any phenotype percentages at any GALT sites among the groups. IgA levels of intestinal washings were significantly higher in the chow group than in any of the IL-7 groups, with similar levels in all IL-7 groups.

CONCLUSIONS

Exogenous IL-7 dose-dependently reverses PN-induced GALT cell loss, with no major changes in small intestinal IgA levels. IL-7 treatment during PN appears to have beneficial effects on gut immunity, but other therapeutic methods are needed to restore secretory IgA levels.

N-3 polyunsaturated fatty acid-enriched lipid emulsion improves Paneth cell function via the IL-22/Stat3 pathway in a mouse model of total parenteral nutrition

Total parenteral nutrition (TPN) is a life-saving therapy for patients with gastrointestinal dysfunction or failure. Long-term TPN impairs gut barrier function and contributes to infections and poor clinical outcomes. However, the underlying mechanisms of TPN-related gut barrier damage have not been fully elucidated, and effective measures are still rare. Here, we compared the effects of a predominantly n-6 polyunsaturated fatty acids emulsion (PUFAs; Intralipid) and a lipid emulsion containing n-3 PUFAs (Intralipid plus Omegaven) on antimicrobial peptides produced by Paneth cells. Our results show for the first time that n-3 PUFAs markedly ameliorated intestine atrophy, and increased protein levels of lysozyme, RegIIIγ, and α-cryptdin 5, and their mRNA expression, compared to the n-6 PUFAs emulsion. Importantly, our study reveals that downregulation of IL-22 and phosphorylated Stat3 (p-Stat3) is associated with Paneth cell dysfunction, which may mediate TPN-related gut barrier damage. Lastly, n-3 PUFAs upregulated levels of IL-22 and increased the p-Stat3/Stat3 ratio in ileal tissue, suggesting that n-3 PUFAs improve Paneth cell function through activation of the IL-22/Stat3 pathway. Therefore, our study provides a cogent explanation for the beneficial effects of n-3 PUFAs, and indicates the IL-22/Stat3 pathway as a promising target in the treatment of TPN-related gut barrier damage.

Pneumatosis Intestinalis in Patients Receiving Tube Feeds

Pneumatosis intestinalis (PI) identified on computed tomography (CT) suggests an underlying pathology including bowel ischemia. Patients receiving tube feeds can develop PI, potentially requiring surgical intervention. We identify clinical factors in PI to predict those that may be safe to observe versus those that need immediate intervention. We retrospectively reviewed patients from a single institution from 2008 to 2016 with CT findings of PI and an enteric feeding tube. Patients who had not received tube feeds within one week of the CT were excluded. We analyzed clinical, operative, and outcome data to differentiate benign from pathologic outcomes. P values < 0.05 were set as significant. Forty patients were identified. We classified 24 as benign (no intervention) and 16 as pathologic (requiring intervention). A pathologic outcome was demonstrated for free fluid on CT [odds ratio (OR) = 5.00, confidence interval (CI) 1.23-20.30, P = 0.03)], blood urea nitrogen (BUN) elevation (OR = 8.27, CI 1.53-44.62, P = 0.01), creatinine (Cr) elevation (OR = 5.00, CI 1.27-19.62, P = 0.02), BUN/Cr ratio >30 (OR = 8.57, CI 1.79-40.98, P = 0.006), and vomiting/ feeding intolerance (OR = 9.38, CI 1.64-53.62, P = 0.01). Bowel function within 24 hours of the CT, bowel dilatation (small ≥ 3 cm; large ≥6 cm), and lactic acidemia were not significant. Peritonitis was only seen in pathologic states, but this did not reach statistical significance (P = 0.06). This represents the largest single-center retrospective analysis of tube feeding-induced PI to date. The presence of free fluid on CT, BUN and Cr elevation, BUN/Cr >30, vomiting/feeding intolerance and peritonitis were predictive of a pathologic etiology of PI.

Total Parenteral and Enteral Nutrition in the ICU: Evolving Concepts

Appropriate nutrition in the hospital setting, particularly in critically ill patients, has long been tied to improving clinical outcomes. During critical illness, inflammatory mediators and cytokines lead to the creation of a catabolic state to facilitate the use of endogenous energy sources to meet increased energy demands. This process results in increasing the likelihood of overfeeding. The literature has revealed exponential advances in understanding the molecular basis of nutritional support and evolution of clinical protocols aimed at treating artificial nutritional support as a therapeutic intervention, preventing loss of lean body mass and metabolic deterioration to improve clinical outcomes in the critically ill.

Gastrointestinal immune and microbiome changes during parenteral nutrition

Parenteral nutrition (PN) is a lifesaving therapy that provides intravenous nutrition support to patients who cannot, or should not, feed via the gastrointestinal (GI) tract. Unfortunately, PN also carries certain risks related to infection and metabolic complications compared with enteral nutrition. In this review, an overview of PN and GI immune and microbiome changes is provided. PN impacts the gut-associated lymphoid tissue functions, especially adaptive immune cells, changes the intestinal epithelium and chemical secretions, and significantly alters the intestinal microbiome. Collectively, these changes functionally result in increased susceptibility to infectious and injurious challenge. Since PN remains necessary in large numbers of patients, the search to improve outcomes by stimulating GI immune function during PN remains of interest. This review closes by describing recent advances in using enteric nervous system neuropeptides or microbially derived products during PN, which may improve GI parameters by maintaining immunity and physiology.

Intestinal Polymeric Immunoglobulin Receptor Is Affected by Type and Route of Nutrition

BACKGROUND

Secretory immunoglobulin A (SIgA) prevents adherence of pathogens at mucosal surfaces to prevent invasive infection. Polymeric immunoglobulin receptor (pIgR) is located on the basolateral surface of epithelial cells and binds dimeric immunoglobulin A (IgA) produced by plasma cells in the lamina propria. This IgA-pIgR complex is transported apically, where IgA is exocytosed as SIgA to the mucosal surface. Our prior work shows that mice fed intragastric (IG, an elemental diet model) and IV parenteral nutrition (PN) solution have reduced intestinal T and B cells, SIgA, and interleukin-4 (IL-4) compared with mice fed chow or a complex enteral diet (CED). Prior work also demonstrates a reduction in IgA transport to mucosal surfaces in IV PN-fed mice. Because IL-4 up-regulates pIgR production, this work studies the effects of these diets on intestinal pIgR.

METHODS

Male Institute of Cancer Research (ICR) mice were randomized to chow (n = 11) with IV catheter, CED (n = 10) or IG PN (n = 11) via gastrostomy and IV PN (n = 12) for 5 days. CED and PN were isocaloric and isonitrogenous. Small intestine was harvested for pIgR and IL-4 assays after mucosal washing for IgA. IgA and IL-4 levels were analyzed by enzyme-linked immunosorbent assay and pIgR by Western blot.

RESULTS

Small intestinal pIgR expression, IgA levels, and IL-4 levels decreased significantly in IV PN and IG PN groups.

CONCLUSIONS

Lack of enteral stimulation affects multiple mechanisms responsible for decreased intestinal SIgA levels, including reduced T and B cells in the lamina propria, reduced Th-2 IgA-stimulating cytokines, and impaired expression of the IgA transport protein, pIgR.

Feeding the Open Abdomen

BACKGROUND

The purpose of this study was to determine if early enteral nutrition improves outcome for trauma patients with an open abdomen (OA).

METHODS

Retrospective review was used to identify 78 patients who required an OA for >or=4 hospital days, survived, and had available nutrition data. Demographic data and nutrition data comprising enteral nutrition initiation day and daily % target goal were collected. Patients were divided into 2 groups: early enteral feeding (EEN), initiated <or=4 days within celiotomy; and late enteral feeding (LEN; >4 days). Outcomes included infectious complications, early closure of the abdominal cavity (<8 days from original celiotomy), and fistula formation.

RESULTS

Fifty-three of 78 (68%) patients were men, with a mean age of 35 years; 74% had blunt trauma. Forty-three of 78 (55%) patients had EEN, whereas 35 of 78 (45%) had LEN. There was no difference with respect to demographics, injury severity, or infectious complication rates. Thirty-two of 43 (74%) patients with EEN had early closure of the abdominal cavity, whereas 17 of 35 (49%) patients with late feeding had early closure (p = .02). Four of 43 (9%) patients with EEN demonstrated fistula formation, whereas 9 of 35 (26%) patients with late feeding formed fistulae (p = .05). The EEN group had lower hospital charges (p = .04) by more than $50,000.

CONCLUSIONS

EEN in the OA was associated with (1) earlier primary abdominal closure, (2) lower fistula rate, (3) lower hospital charges.

When Is Parenteral Nutrition Appropriate?

Parenteral nutrition (PN) represents one of the most notable achievements of modern medicine, serving as a therapeutic modality for all age groups across the healthcare continuum. PN offers a life-sustaining option when intestinal failure prevents adequate oral or enteral nutrition. However, providing nutrients by vein is an expensive form of nutrition support, and serious adverse events can occur. In an effort to provide clinical guidance regarding PN therapy, the Board of Directors of the American Society for Parenteral and Enteral Nutrition (ASPEN) convened a task force to develop consensus recommendations regarding appropriate PN use. The recommendations contained in this document aim to delineate appropriate PN use and promote clinical benefits while minimizing the risks associated with the therapy. These consensus recommendations build on previous ASPEN clinical guidelines and consensus recommendations for PN safety. They are intended to guide evidence-based decisions regarding appropriate PN use for organizations and individual professionals, including physicians, nurses, dietitians, pharmacists, and other clinicians involved in providing PN. They not only support decisions related to initiating and managing PN but also serve as a guide for developing quality monitoring tools for PN and for identifying areas for further research. Finally, the recommendations contained within the document are also designed to inform decisions made by additional stakeholders, such as policy makers and third-party payers, by providing current perspectives regarding the use of PN in a variety of healthcare settings.

The Efficacy of an Enteral Access Protocol for Feeding Trauma Patients

BACKGROUND

Proper enteral access to deliver specialized nutrition support in critically injured patients can be difficult, time consuming, and costly. We designed a protocol with interdisciplinary input to facilitate early enteral access in our trauma patients. Our primary objective was to determine if the protocol improved our ability to obtain small-bowel access in patients within 48 hours of their admission to the surgical intensive care unit (SICU). Secondary objectives were to examine the efficacy of the protocol by evaluating parenteral nutrition (PN) use, adequacy of enteral caloric delivery, and clinical outcomes including pneumonia and sepsis rates, SICU length of stay (LOS), hospital LOS, and mortality before and after its implementation.

METHODS

The medical records of 51 trauma patients admitted to the SICU, who met inclusion criteria, were reviewed retrospectively and divided into 2 groups. Patients in group 1 were admitted before protocol implementation (1997-1998, n = 17). Patients in group 2 were admitted after protocol implementation (1998-2000, n = 34).

RESULTS

Small-bowel access was achieved earlier in group 2 compared with group 1 [2.2 +/- 2 days vs 5.4 +/- 8 days, respectively (p = .04)]. PN was used less frequently in group 2 at 41.2% (14/34) as opposed to 64.7% (11/17) in group 1 (p = .05). There was a reduction in the number of days to reach caloric goal from 4.9 days in group 1 to 3.9 days in group 2 (n.s.). Clinical outcomes were similar in both groups.

CONCLUSIONS

The use of a protocol was effective in the achievement of prompt small bowel access. The number of days to reach caloric goal decreased after protocol implementation, but not to a statistically significant degree. However, we were able to detect a significant reduction in the use of PN.

Defining and Assessing Tolerance in Enteral Nutrition

Nutrition support has become widely recognized as an essential component of optimal care for acutely ill patients. Enteral nutrition is preferred over parenteral routes when possible. However, prescribed enteral nutritional regimens are sometimes met with side effects and even complications. These adverse events have been collectively termed "intolerance," and forms of intolerance occur in a spectrum from bothersome at least to life threatening when most severe. Here we discuss nutritional access and its maintenance, introduce and define intolerance, and then review the current literature with regard to principal forms of enteral nutrition intolerance.

Fistuloclysis: Case Report and Literature Review

Enterocutaneous fistulae are a common postoperative entity, causing serious complications such as sepsis, malnutrition, and electrolyte and fluid abnormalities. Because sepsis coupled with malnutrition is the leading cause of death in these patients, it is especially important to provide nutrition support. Although parenteral nutrition (PN) is widely used in these patients, it is not without risks, because PN is known to cause liver dysfunction, among other problems. We report a case in which a male patient with an enterocutaneous fistula, having experienced increased liver enzymes receiving PN, began receiving enteral nutrition (EN) via a feeding tube placed in the fistula. Known as fistuloclysis, this method provided adequate nutrition and improved his serum albumin and prealbumin levels, body weight, and liver function tests. Upon stabilization of his nutrition status, he was able to undergo successful surgical repair of the enterocutaneous fistula. According to our experience and that of others, we recommend that patients with high-output enterocutaneous fistulae be considered for EN via fistuloclysis after nutrition stabilization with PN; then the fistulae can be surgically repaired if not spontaneously healed. Use of EN via fistuloclysis, if used appropriately, avoids the complications of long-term PN and may promote faster fistula healing.

Enteral Access in Mechanically Ventilated Patients

The early institution of enteral nutrition is now accepted as the preferred route of feeding in critically ill patients with a functioning gastrointestinal tract. It is particularly important to establish early enteral nutrition in mechanically ventilated patients because of the metabolic demands associated with mechanical ventilation. The options for enteral access in mechanically ventilated patients are reviewed, with an emphasis on those techniques that may be performed at the bedside. The advantages, disadvantages, and complications of the different techniques will be considered.

Lack of Enteral Nutrition Delays Nuclear Factor Kappa B Activation in Peritoneal Exudative Cells in a Murine Glycogen-Induced Peritonitis Model

BACKGROUND

Early enteral nutrition is associated with a lower incidence of intraabdominal abscess in severely injured patients than parenteral nutrition (PN). We explored the underlying mechanisms by examining the influence of nutrition route on nuclear factor kappaB (NFkappaB) activation in peritoneal exudative cells (PECs) and peritoneal cytokine levels.

METHODS

Thirty male Institute Cancer Research mice were randomized to chow (n = 10), IV PN (n = 10), or intragastric (IG) PN (n = 10) and fed for 5 days. PECs were harvested at 2 or 4 hours after intraperitoneal injection of 2 mL of 1% glycogen. Intranuclear NFkappaB activity in PECs was examined by laser scanning cytometry. Cytokine (tumor necrosis factor-alpha [TNF-alpha], macrophage inflammatory protein-2 [MIP-2], interleukin-10 [IL-10]) levels in peritoneal lavaged fluid were determined by enzyme-linked immunosorbent assay.

RESULTS

Intranuclear NFkappaB at 2 hours was significantly higher in the chow and IG-PN groups than in the IV-PN group. TNF-alpha and IL-10 levels of the chow group were significantly higher than those of IV-PN mice at 2 hours, whereas those of IG-PN mice were midway between those of the chow and IV-PN groups. MIP-2 was significantly higher in the chow group than in the IG-PN and IV-PN mice at 2 hours. TNF-alpha levels correlated positively with intranuclear NFkappaB activity in PECs.

CONCLUSIONS

Enteral nutrition may improve peritoneal defense by preserving early NFkappaB activation in PECs and cytokine responses.

A Randomized Controlled Trial Comparing Three Different Techniques of Nasojejunal Feeding Tube Placement in Critically Ill Children

BACKGROUND

The goal of this study was to compare 3 different techniques used to place nasojejunal (NJ) feeding tubes in the critically ill or injured pediatric patients. This was a randomized, prospective trial in a university-affiliated 12-bed pediatric intensive care unit. Patients were critically ill children requiring placement of an NJ feeding tube. Patient age, weight, medications, use of mechanical ventilation, and patient tolerance were recorded. An abdominal radiograph obtained immediately after the placement determined correct placement. The final placement was recorded, as was the number of placement attempts.

METHODS

Patients were randomized to 1 of 3 groups: standard technique, standard technique facilitated with gastric insufflation, and standard technique facilitated with the use of preinsertion erythromycin. To ensure equal distribution, all patients were stratified by weight (<10 kg vs > or =10 kg) before randomization. All NJ tubes were placed by one of the investigators. If unsuccessful, a second attempt by the same investigator was allowed. Successful placement of the NJ tube was defined by confirmation of the tip of the tube in the first part of the duodenum or beyond by a pediatric radiologist blinded to the treatment groups.

RESULTS

Seventy-five pediatric patients were enrolled in the study; 94.6% (71/75) of tubes were passed successfully into the small bowel on the first or second attempt. Evaluation of the data revealed no significant association with a specific technique and successful placement (p = .1999).

CONCLUSIONS

When placed by a core group of experienced operators, the majority of NJ feeding tubes can be placed in critically ill or injured children on the first or second attempt, regardless of the technique used.

A New Graduated Dosing Regimen for Phosphorus Replacement in Patients Receiving Nutrition Support

BACKGROUND

Hypophosphatemia is a common metabolic complication in patients receiving specialized nutrition support. We changed our previously reported dosing algorithm because the low dose no longer appeared to be effective at increasing serum phosphorus concentrations. The purpose of this study was to evaluate the safety and efficacy of a revised weight-based phosphorus-dosing algorithm in critically ill trauma patients receiving specialized nutrition support.

METHODS

Seventy-nine adult trauma patients with hypophosphatemia (serum phosphorus concentration < or = 0.96 mmol/L) receiving nutrition support received an IV dose of phosphorus on day 1 according to the serum concentration of phosphorus: 0.73-0.96 mmol/L (0.32 mmol/kg, low dose), 0.51-0.72 mmol/L (0.64 mmol/kg, moderate dose), and < or = 0.5 mmol/L (1 mmol/kg, high dose). The IV phosphorus bolus dose was administered at 7.5 mmol/hour. Generally, patients with a serum potassium concentration <4 mmol/L received potassium phosphate and patients with a serum potassium concentration > or = 4 mmol/L received sodium phosphate. Patients who still had hypophosphatemia on day 2 were dosed using the new dosing algorithm by the nutrition support service according to that day's serum concentration of phosphorus, or empirically by the trauma service.

RESULTS

Of the 79 patients studied, 57 were male and 22 were female with a mean age of 44.8 +/- 20.6 years. Mean Injury Severity Scores and APACHE-II scores were 27.1 +/- 11.6 and 15.2 +/- 6.8, respectively. There was no difference in baseline characteristics among the 3 dosing groups. Of the 79 patients, 34 received the low dose, 30 received the moderate dose, and 15 received the high dose of phosphorous. Mean serum phosphorous concentrations on day 2 were significantly increased in the moderate-dosed group (0.64 +/- 0.06 to 0.77 +/- 0.22 mmol/L, p < .05) and high-dosed group (0.38 +/- 0.06 to 0.93 +/- 0.32 mmol/L, p < .01), respectively, when compared with day 1. Mean serum phosphorus concentrations were normal in all 3 groups on day 3. Serum concentrations of magnesium, sodium, and potassium, as well as arterial pH, were stable across the study. Mean concentrations of ionized calcium were not significantly different in any of the 3 dosing groups across the study period.

CONCLUSIONS

This weight-based phosphorus-dosing algorithm is safe for use in critically ill patients receiving nutrition support. The moderate and severe-dose regimens effectively increase serum phosphorus concentrations.

Ghrelin improves intestinal mucosal atrophy during parenteral nutrition: An experimental study

BACKGROUND/PURPOSE

Total parenteral nutrition (TPN) has been reported to be associated with mucosal atrophy of the small intestine. Ghrelin has hormonal, orexigenic, and metabolic activities. We investigated whether ghrelin improved intestinal mucosal atrophy using a TPN-supported rat model.

METHODS

Rats underwent jugular vein catheterization and were divided into four groups: TPN alone (TPN), TPN plus low-dose ghrelin (TPNLG), TPN plus high-dose ghrelin (TPNHG), and oral feeding with normal chow (OF). Ghrelin was administered continuously at dosages of 10 or 50 μg/kg/day. On day 6 rats were euthanized, and the small intestine was harvested and divided into the jejunum and ileum. Then the villus height (VH) and crypt depth (CD) were evaluated.

RESULTS

The jejunal and ileal VH and CD in the TPN group were significantly decreased compared with those in the OF group. TPNHG improved only VH of the jejunum. TPNLG improved VH and CD of the jejunum and CD of the ileum. The improvement of TPNLG was significantly stronger than that in CD of the jejunum and ileum.

CONCLUSIONS

TPN was more strongly associated with mucosal atrophy in the jejunum than in the ileum. Low-dose intravenous administration of ghrelin improved TPN-associated intestinal mucosal atrophy more effectively than high-dose administration.

The History of Nonsurgical Enteral Tube Feeding Access

Specialized nutrition support, particularly enteral feeding, has been used for centuries. Technologic advancements have affected the provision of enteral feeding. Feeding solutions and devices, as well as the techniques to place the feeding devices, have evolved. This article reviews the history of bedside placement methods for short-term enteral access devices.

Nutrition Support in Adult Trauma Patients

Nutrition supplementation is paramount to the care of severely injured patients. Despite its widespread use in trauma patients, many areas of clinical practice remain controversial. The purpose of this paper is to critically review the literature studying the use of enteral vs parenteral nutrition (PN) and to provide the rationale for early enteral nutrition. Additional controversies confronting clinicians are reviewed, including the use of immune-enhancing agents and the optimal site for enteral nutrition delivery (gastric vs small intestinal). Evidence-based recommendations for clinical practice are presented when available.

Bacterial nutrient foraging in a mouse model of enteral nutrient deprivation: insight into the gut origin of sepsis

Total parenteral nutrition (TPN) leads to a shift in small intestinal microbiota with a characteristic dominance of Proteobacteria This study examined how metabolomic changes within the small bowel support an altered microbial community in enterally deprived mice. C57BL/6 mice were given TPN or enteral chow. Metabolomic analysis of jejunal contents was performed by liquid chromatography/mass spectrometry (LC/MS). In some experiments, leucine in TPN was partly substituted with [¹³C]leucine. Additionally, jejunal contents from TPN-dependent and enterally fed mice were gavaged into germ-free mice to reveal whether the TPN phenotype was transferrable. Small bowel contents of TPN mice maintained an amino acid composition similar to that of the TPN solution. Mass spectrometry analysis of small bowel contents of TPN-dependent mice showed increased concentration of ¹³C compared with fed mice receiving saline enriched with [¹³C]leucine. [¹³C]leucine added to the serosal side of Ussing chambers showed rapid permeation across TPN-dependent jejunum, suggesting increased transmucosal passage. Single-cell analysis by fluorescence in situ hybridization (FISH)-NanoSIMS demonstrated uptake of [¹³C]leucine by TPN-associated bacteria, with preferential uptake by Enterobacteriaceae Gavage of small bowel effluent from TPN mice into germ-free, fed mice resulted in a trend toward the proinflammatory TPN phenotype with loss of epithelial barrier function. TPN dependence leads to increased permeation of TPN-derived nutrients into the small intestinal lumen, where they are predominately utilized by Enterobacteriaceae The altered metabolomic composition of the intestinal lumen during TPN promotes dysbiosis.

Nutritional controversies in critical care: revisiting enteral glutamine during critical illness and injury

PURPOSE OF REVIEW

This article examines some of the articles that inspired recent changes to critical care guidelines related to glutamine in enteral nutrition.

RECENT FINDINGS

Two recent multicenter randomized controlled trials involving enteral glutamine have reported increased mortality rates in groups of mechanically ventilated adult patients, while demonstrating no additional benefits to other outcomes, such as nosocomial infections.

SUMMARY

Recent studies suggest that enteral glutamine supplementation may not provide significant clinical benefits to adult patients on mechanical ventilation with multiple organ failure, but more information is still needed when attempting to apply these results to other groups of critical care patients.

The efficacy and safety of prokinetic agents in critically ill patients receiving enteral nutrition: a systematic review and meta-analysis of randomized trials

Background

Intolerance to enteral nutrition is common in critically ill adults, and may result in significant morbidity including ileus, abdominal distension, vomiting and potential aspiration events. Prokinetic agents are prescribed to improve gastric emptying. However, the efficacy and safety of these agents in critically ill patients is not well-defined. Therefore, we conducted a systematic review and meta-analysis to determine the efficacy and safety of prokinetic agents in critically ill patients.

Methods

We searched MEDLINE, EMBASE, and Cochrane Library from inception up to January 2016. Eligible studies included randomized controlled trials (RCTs) of critically ill adults assigned to receive a prokinetic agent or placebo, and that reported relevant clinical outcomes. Two independent reviewers screened potentially eligible articles, selected eligible studies, and abstracted pertinent data. We calculated pooled relative risk (RR) for dichotomous outcomes and mean difference for continuous outcomes, with the corresponding 95 % confidence interval (CI). We assessed risk of bias using Cochrane risk of bias tool, and the quality of evidence using grading of recommendations assessment, development, and evaluation (GRADE) methodology.

Results

Thirteen RCTs (enrolling 1341 patients) met our inclusion criteria. Prokinetic agents significantly reduced feeding intolerance (RR 0.73, 95 % CI 0.55, 0.97; P = 0.03; moderate certainty), which translated to 17.3 % (95 % CI 5, 26.8 %) absolute reduction in feeding intolerance. Prokinetics also reduced the risk of developing high gastric residual volumes (RR 0.69; 95 % CI 0.52, 0.91; P = 0.009; moderate quality) and increased the success of post-pyloric feeding tube placement (RR 1.60, 95 % CI 1.17, 2.21; P = 0.004; moderate quality). There was no significant improvement in the risk of vomiting, diarrhea, intensive care unit (ICU) length of stay or mortality. Prokinetic agents also did not significantly increase the rate of diarrhea.

Conclusion

There is moderate-quality evidence that prokinetic agents reduce feeding intolerance in critically ill patients compared to placebo or no intervention. However, the impact on other clinical outcomes such as pneumonia, mortality, and ICU length of stay is unclear.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1441-z) contains supplementary material, which is available to authorized users.

Tolerability of Enteral Nutrition in Mechanically Ventilated Patients With Septic Shock Who Require Vasopressors

Purpose:

Enteral nutrition (EN) is often held in patients receiving vasopressor support for septic shock. The rationale for this practice is to avoid mesenteric ischemia. The objective of this study is to evaluate the tolerability of EN in patients with septic shock who require vasopressor support and determine factors associated with tolerance of EN.

Materials and Methods:

This was a single-center retrospective review of adult patients admitted to the intensive care unit with a diagnosis of septic shock and an order for EN. The primary outcome was EN tolerance. Secondary outcomes included time to initiation of EN from the start of vasopressor(s), length of stay, and mortality.

Results:

A total of 120 patients were included. Sixty-two percent of patients tolerated EN. The most common reason for intolerance of EN was gastric residuals > 250 mL (74%). No reports of mesenteric ischemia were observed. A multivariate analysis demonstrated that patients with septic shock initiating EN within 48 hours and receiving norepinephrine-equivalent doses of 0.14 μg/kg/min or less were more likely to tolerate EN.

Conclusion:

Based on our observation, early EN may be tolerated and safely administered in patients with septic shock who are adequately fluid resuscitated and receive doses of < 0.14 μg/kg/min of norepinephrine equivalents.

Current Concepts in Severe Sepsis and Septic Shock

Sepsis is a frequent cause of presentation to the emergency department (ED). Early identification and aggressive management in the ED is paramount to improving morbidity and mortality associated with sepsis. As a result, pharmacists in the ED should be familiar with and assist with the optimization of therapy for sepsis in this patient population. This article will discuss the epidemiology and economic impact of sepsis and the definitions, pathophysiology, and clinical presentation of sepsis and its related syndromes. In addition, the authors will discuss the elements related to treatment of sepsis from the Surviving Sepsis Campaign Guidelines that are particularly germane to the management of sepsis in the ED. Direct support such as source control, early broad-spectrum antibiotic therapy, hemodynamic assessment, and continuous monitoring are essential. In addition, early aggressive fluid resuscitation with titration of therapy to mixed venous oxygen saturation >70%, tight glycemic control and choice of vasopressors and inotropes have been shown to decrease mortality in sepsis. Mechanical ventilation with low tidal volumes, renal replacement therapies, early enteral nutritional support, and stress ulcer prophylaxis are also important considerations in septic patients. Controversies in therapy such as the utility of drotrecogin α activated, low-dose corticosteroids, and vasopressin are also discussed.