Tolerability of bolus versus continuous gastric feeding in brain-injured patients

Nutrition Therapy for Patients With Traumatic Brain Injury: A Narrative Review

Traumatic brain injury (TBI) is a global health and socio-economic problem, resulting in significant disability and mortality. Malnutrition is common in TBI patients and is associated with increased vulnerability to infection, higher morbidity and mortality rates, as well as longer stays in the intensive care unit and hospital. Following TBI, various pathophysiological mechanisms, such as hypermetabolism and hypercatabolism, affect patient outcomes. It is crucial to provide adequate nutrition therapy to prevent secondary brain damage and promote optimal recovery. This review includes a literature review and discusses the challenges encountered in clinical practice regarding nutrition in TBI patients. The focus is on determining energy requirements, timing and methods of nutrition delivery, promoting enteral tolerance, providing enteral nutrition to patients receiving vasopressors, and implementing trophic enteral nutrition. Enhancing our understanding of the current evidence regarding appropriate nutrition practices will contribute to improving overall outcomes for TBI patients.

Comparison of continuous versus intermittent enteral feeding in critically ill patients: a systematic review and meta-analysis

Background

The enteral route is commonly utilised to support the nutritional requirements of critically ill patients. However, there is paucity of data guiding clinicians regarding the appropriate method of delivering the prescribed dose. Continuous enteral feeding is commonly used; however, a bolus or intermittent method of administration may provide several advantages such as minimising interruptions. The purpose of this meta-analysis is to compare a continuous versus an intermittent or bolus enteral nutrition administration method.

Methods

A systematic review and meta-analysis were performed with studies identified from the PubMed, EMBASE, Cochrane Library and Web of Science databases. Studies were included if they compared a continuous with either an intermittent or bolus administration method of enteral nutrition in adult patients admitted to the intensive care unit. Study quality was assessed using the PEDro and Newcastle–Ottawa scoring systems. Review Manager was used for performing the random-effects meta-analysis on the outcomes of mortality, constipation, diarrhoea, increased gastric residuals, pneumonia, and bacterial colonisation.

Results

A total of 5546 articles were identified, and 133 were included for full text review. Fourteen were included in the final analysis. There was an increased risk of constipation with patients receiving continuous enteral nutrition (relative risk 2.24, 95% confidence interval 1.01–4.97, p = 0.05). No difference was identified in other outcome measures. No appreciable bias was identified.

Conclusion

The current meta-analysis has not identified any clinically relevant difference in most outcome measures relevant to the care of critically ill patients. However, there is a paucity of high-quality randomised controlled clinical trials to guide this decision. Therefore, clinicians may consider either dosing regimen in the context of the patient’s care requirements.

Optimizing Sleep and Circadian Health in the NeuroICU

Purpose of Review

This article introduces fundamental concepts in circadian biology and the neuroscience of sleep, reviews recent studies characterizing circadian rhythm and sleep disruption among critically ill patients and potentially links to functional outcomes, and draws upon existing literature to propose therapeutic strategies to mitigate those harms. Particular attention is given to patients with critical neurologic conditions and the unique environment of the neuro-intensive care unit.

Recent Findings

Circadian rhythm disruption is widespread among critically ill patients and sleep time is reduced and abnormally fragmented. There is a strong association between the degree of arousal suppression observed at the bedside and the extent of circadian disruption at the system (e.g., melatonin concentration rhythms) and cellular levels (e.g., core clock gene transcription rhythms). There is a paucity of electrographically normal sleep, and rest-activity rhythms are severely disturbed. Common care interventions such as neurochecks introduce unique disruptions in neurologic patients. There are no pharmacologic interventions proven to normalize circadian rhythms or restore physiologically normal sleep. Instead, interventions are focused on reducing pharmacologic and environmental factors that perpetuate disruption.

Summary

The intensive care environment introduces numerous potent disruptors to sleep and circadian rhythms. Direct neurologic injury and neuro-monitoring practices likely compound those factors to further derange circadian and sleep functions. In the absence of direct interventions to induce normalized rhythms and sleep, current therapy depends upon normalizing external stimuli.

Nutritional Support for Pediatric Severe Traumatic Brain Injury

In critically ill children with severe traumatic brain injury (sTBI), nutrition may help facilitate optimal recovery. There is ongoing research regarding nutritional practices in the pediatric intensive care unit (PICU). These are focused on identifying a patient's most appropriate energy goal, the mode and timing of nutrient delivery that results in improved outcomes, as well as balancing these goals against inherent risks associated with nutrition therapy. Within the PICU population, children with sTBI experience complex physiologic derangements in the acute post-injury period that may alter metabolic demand, leading to nutritional needs that may differ from those in other critically ill patients. Currently, there are relatively few studies examining nutrition practices in PICU patients, and even fewer studies that focus on pediatric sTBI patients. Available data suggest that contemporary neurocritical care practices may largely blunt the expected hypermetabolic state after sTBI, and that early enteral nutrition may be associated with lower morbidity and mortality. In concordance with these data, the most recent guidelines for the management of pediatric sTBI released by the Brain Trauma Foundation recommend initiation of enteral nutrition within 72 h to improve outcome (Level 3 evidence). In this review, we will summarize available literature on nutrition therapy for children with sTBI and identify gaps for future research.

Safety and Efficacy of Continuous or Intermittent Enteral Nutrition in ICU Patients: Systematic Review of Clinical Evidence

The best mode of delivering enteral nutrition (EN) in ICU is still debated: several consensus guidelines (ASPEN and ESPEN) suggest that EN in ICU should be preferably delivered continuously rather intermittently but some authors highlight that the first is unphysiological. The aim of this systematic review (SR) is to summarize available clinical evidence related to safety and efficacy of continuous enteral nutrition (C-EN) or intermittent enteral nutrition (I-EN) in ICU patients, in relation to appropriated supply on nutritional status, gastrointestinal symptoms or tolerance, risks on respiratory tract infections. A literature search of Pubmed, EMBASE and Google Scholar was performed comparing C-EN vs I-EN and 4196 published studies were screened. Nineteen studies were selected for this SR reporting types of ICU, nutritional protocols and study period. Effects of C-EN vs I-EN were presented according to the impact on: nutritional status, digestive tract and respiratory tract. The contrasting results confirmed that the optimal delivering mode of EN remains controversial. Future studies dedicated to identify the benefits and limitations of C-EN or I-EN should be realized. This article is protected by copyright. All rights reserved.

Oropharyngeal Dysphagia and Impaired Motility of the Upper Gastrointestinal Tract-Is There a Clinical Link in Neurocritical Care?

Patients in the neurological ICU are at risk of suffering from disorders of the upper gastrointestinal tract. Oropharyngeal dysphagia (OD) can be caused by the underlying neurological disease and/or ICU treatment itself. The latter was also identified as a risk factor for gastrointestinal dysmotility. However, its association with OD and the impact of the neurological condition is unclear. Here, we investigated a possible link between OD and gastric residual volume (GRV) in patients in the neurological ICU. In this retrospective single-center study, patients with an episode of mechanical ventilation (MV) admitted to the neurological ICU due to an acute neurological disease or acute deterioration of a chronic neurological condition from 2011–2017 were included. The patients were submitted to an endoscopic swallowing evaluation within 72 h of the completion of MV. Their GRV was assessed daily. Patients with ≥1 d of GRV ≥500 mL were compared to all the other patients. Regression analysis was performed to identify the predictors of GRV ≥500 mL/d. With respect to GRV, the groups were compared depending on their FEES scores (0–3). A total of 976 patients were included in this study. A total of 35% demonstrated a GRV of ≥500 mL/d at least once. The significant predictors of relevant GRV were age, male gender, infratentorial or hemorrhagic stroke, prolonged MV and poor swallowing function. The patients with the poorest swallowing function presented a GRV of ≥500 mL/d significantly more often than the patients who scored the best. Conclusions: Our findings indicate an association between dysphagia severity and delayed gastric emptying in critically ill neurologic patients. This may partly be due to lesions in the swallowing and gastric network.

Risk Assessment of Intermittent and Continuous Nasogastric Enteral Feeding Methods in Adult Inpatients: A Meta-Analysis

Diarrhea and pneumonia are common and serious complications in hospitalized patients requiring nasogastric enteral feeding. Our study aimed to compare the risk of diarrhea and pneumonia between intermittent nasogastric enteral feeding (IEF) and continuous nasogastric enteral feeding (CEF). We systematically searched PubMed, Web of Science, and Cochrane for relevant articles published from August 9, 1992, to September 1, 2019. A total of 637 IEF and CEF patients were included in our meta-analysis. Odds ratios (ORs) with associated 95% confidence intervals (CIs) were calculated to estimate the effects of diarrhea and pneumonia. We showed that hospital patients that required IEF had an increased risk of diarrhea compared with CEF. In the subgroup analyses, similar conclusions were identified in the non-China group and small sample size group (size < 100). However, our results showed no significant differences in the China group or large sample size group (size ≥ 100). Furthermore, our analysis showed that no significant association was observed for the risk of pneumonia between IEF and CEF patients. For inpatients requiring nasogastric enteral feeding, CEF is a better method of enteral nutrition compared with IEF, of which patients experience a significantly increased risk of diarrhea.

Intermittent or continuous feeding: any difference during the first week?

PURPOSE OF REVIEW

To balance theoretical pros and cons of intermittent feeding, in light of the current nutritional management early during critical illness.

RECENT FINDINGS

Less aggressive nutrient administration is clinically superior in acute critical illness. This counterintuitive clinical finding may be explained by nutrient restriction activating autophagy, a process that clears intracellular damage. Intermittent feeding holds numerous theoretical benefits, such as activation of autophagy, preservation of the circadian rhythm, increased protein synthesis, and enhanced endogenous fatty acids release. RCTs investigating intermittent feeding in the ICU, however, are the most often limited to evaluation of gastrointestinal complications. Current guidelines advocate against the use of intermittent feeding, based on lack of benefit and increased risk of diarrhea, as revealed by a meta-analysis.

SUMMARY

Benefits of intermittent feeding in the ICU are today speculative, yet its potential impact may reach far beyond the gastrointestinal tract. Only adequately powered RCTs, evaluating both gastrointestinal tolerance, metabolic impact and patient-centered effects of intermittent feeding will allow to adopt or abort this nutritional strategy.

Enteral Nutrition Initiation in Children Admitted to Pediatric Intensive Care Units After Traumatic Brain Injury

BACKGROUND

Traumatic brain injury (TBI) is the leading cause of death and long-term disability among injured children. Early feeding has been shown to improve outcomes in adults, with some similar evidence in children with severe TBI. We aimed to examine the current practice of initiation of enteral nutrition in children with TBI and to evaluate the risk factors associated with delayed initiation of enteral nutrition.

METHODS

This retrospective, multicenter study used the Pediatric Trauma Assessment and Management Database including all children with head trauma discharged from five pediatric intensive care units (PICU) at pediatric trauma centers between January 1, 2013 and December 31, 2013. We compared demographics, injury and procedure data, time to initiation of nutrition, and injury and illness severity scores between patients who received enteral nutrition early (≤ 48 h) and late (> 48 h). Fisher's exact and Mann-Whitney U tests compared discrete and continuous variables. Univariate and multivariable analyses evaluated variables associated with delayed initiation of feeding. Outcomes of interest included mortality, complications, ventilator days, hospital and ICU length of stay, and functional status at ICU discharge.

RESULTS

In the 416 patients in the study, the overall mortality was 2.6%. The majority of patients (83%; range 69-88% between five sites, p = 0.0008) received enteral nutrition within 48 h of PICU admission. Lower Glasgow Coma Scale scores and higher Injury Severity Score (ISS) were independently associated with delayed initiation of enteral nutrition. Delayed enteral nutrition was independently associated with worse functional status at PICU discharge (p = 0.02) but was not associated with mortality or increased length of stay.

CONCLUSIONS

Children with severe TBI and higher ISS were more likely to have delayed initiation of enteral nutrition. Delayed enteral nutrition was an independent risk factor for worse functional status at ICU discharge for the entire cohort, but not for the severe TBI group.

ESPEN guideline on clinical nutrition in the intensive care unit

Following the new ESPEN Standard Operating Procedures, the previous guidelines to provide best medical nutritional therapy to critically ill patients have been updated. These guidelines define who are the patients at risk, how to assess nutritional status of an ICU patient, how to define the amount of energy to provide, the route to choose and how to adapt according to various clinical conditions. When to start and how to progress in the administration of adequate provision of nutrients is also described. The best determination of amount and nature of carbohydrates, fat and protein are suggested. Special attention is given to glutamine and omega-3 fatty acids. Particular conditions frequently observed in intensive care such as patients with dysphagia, frail patients, multiple trauma patients, abdominal surgery, sepsis, and obesity are discussed to guide the practitioner toward the best evidence based therapy. Monitoring of this nutritional therapy is discussed in a separate document.

Clinical chronobiology: a timely consideration in critical care medicine

A fundamental aspect of human physiology is its cyclical nature over a 24-h period, a feature conserved across most life on Earth. Organisms compartmentalise processes with respect to time in order to promote survival, in a manner that mirrors the rotation of the planet and accompanying diurnal cycles of light and darkness. The influence of circadian rhythms can no longer be overlooked in clinical settings; this review provides intensivists with an up-to-date understanding of the burgeoning field of chronobiology, and suggests ways to incorporate these concepts into daily practice to improve patient outcomes. We outline the function of molecular clocks in remote tissues, which adjust cellular and global physiological function according to the time of day, and the potential clinical advantages to keeping in time with them. We highlight the consequences of "chronopathology", when this harmony is lost, and the risk factors for this condition in critically ill patients. We introduce the concept of "chronofitness" as a new target in the treatment of critical illness: preserving the internal synchronisation of clocks in different tissues, as well as external synchronisation with the environment. We describe methods for monitoring circadian rhythms in a clinical setting, and how this technology may be used for identifying optimal time windows for interventions, or to alert the physician to a critical deterioration of circadian rhythmicity. We suggest a chronobiological approach to critical illness, involving multicomponent strategies to promote chronofitness (chronobundles), and further investment in the development of personalised, time-based treatment for critically ill patients.

Gastrointestinal dysmotility in critically ill patients

Gastrointestinal (GI) motility disorders are commonly present in critical illness. Up to 60% of critically ill patients have been reported to experience GI dysmotility of some form necessitating therapeutic intervention. It has been attributed to various factors, related to both the underlying disease and the therapeutic interventions undertaken. The assessment of motility disturbances can be challenging in critically ill patients, as the available tests used to detect abnormal motility have major limitations in the setting of an Intensive Care Unit. Critically ill patients with GI dysmotility require a multifaceted treatment approach that addresses multiple causes and utilizes multiple pharmacological pathways. In this review, we discuss the pathophysiology, assessment and management of GI dysmotility in critically ill patients.

Energy Expenditure in Patients With Nontraumatic Intracranial Hemorrhage

BACKGROUND

Patients with intracerebral (ICH), intraventricular (IVH) and subarachnoid hemorrhage (SAH) have increased morbidity and mortality compared with other forms of stroke. We postulate that the systemic inflammatory state triggered by these forms of nontraumatic intracranial hemorrhage (IH) translates into higher nutrition requirements than traditionally assumed. In order to test this hypothesis, we performed a retrospective study comparing the resting energy expenditure (REE) of 14 mechanically ventilated IH patients with the REE of 6 severe traumatic brain injury (sTBI) patients (a disease known to induce an increased metabolic state).

METHODS

Using nonparametric analysis, we compared 2 contemporary cohorts of patients-IH and sTBI-who required mechanical ventilation and who underwent indirect calorimetry (IC) within 7 days after the ictus.

RESULTS

Fourteen patients with nontraumatic IH (IVH, 2; SAH, 9; SAH/ICH, 1; ICH/SAH/IVH, 2) who underwent IC within 7 days from injury were identified; median age: 59 (28-84) years, median admission Glasgow Coma Scale (GCS): 6 (4-9), and median APACHE II: 19.5 (15-28). A control cohort of 6 patients with sTBI was identified; median age: 57.5 (18-80) years, admission GCS: 6.5 (4-8), and APACHE II: 16 (11-31). Sedation was used in 11/14 patients with IH and in 5/6 severe TBI patients. No patient was pharmacologically paralyzed. Median REE was 1810 (1124-2806) and 2238 (1860-2780) kcal/d for the IH and for the sTBI patient cohorts, respectively. Using Wilcoxon signed ranks test, the 2 patient groups were found comparable in regard to baseline clinical variables and disease severity (APACHE II). We did not identify a statistically significant difference in the REE between these 2 cohorts of patients (p = .25).

CONCLUSIONS

Patients with severe TBI and patients with IH have similar increments in metabolic rate during the initial phase (1 week from onset) of their disease. This information needs to be confirmed in a larger cohort of patients. If reproduced, our results suggest that nontraumatic IH patients are at high risk of inadequate nutrition if their metabolic rate is estimated after conventional nutrition practice.

Continuous versus bolus tube feeds: Does the modality affect glycemic variability, tube feeding volume, caloric intake, or insulin utilization?

Introduction:

Enteral nutrition (EN) is very important to optimizing outcomes in critical illness. Debate exists regarding the best strategy for enteral tube feeding (TF), with concerns that bolus TF (BTF) may increase glycemic variability (GV) but result in fewer nutritional interruptions than continuous TF (CTF). This study examines if there is a difference in GV, insulin usage, TF volume, and caloric delivery among intensive care patients receiving BTF versus CTF. We hypothesize that there are no significant differences between CTF and BTF when comparing the above parameters.

Materials and Methods:

Prospective, randomized pilot study of critically ill adult patients undergoing percutaneous endoscopic gastrostomy (PEG) placement for EN was performed between March 1, 2012 and May 15, 2014. Patients were randomized to BTF or CTF. Glucose values, insulin use, TF volume, and calories administered were recorded. Data were organized into 12-h epochs for statistical analyses and GV determination. In addition, time to ≥80% nutritional delivery goal, demographics, Acute Physiology and Chronic Health Evaluation II scores, and TF interruptions were examined. When performing BTF versus CTF assessments, continuous parameters were compared using Mann–Whitney U-test or repeated measures t-test, as appropriate. Categorical data were analyzed using Fisher's exact test.

Results:

No significant demographic or physiologic differences between the CTF (n = 24) and BTF (n = 26) groups were seen. The immediate post-PEG 12-h epoch showed significantly lower GV and median TF volume for patients in the CTF group. All subsequent epochs (up to 18 days post-PEG) showed no differences in GV, insulin use, TF volume, or caloric intake. Insulin use for both groups increased when comparing the first 24 h post-PEG values to measurements from day 8. There were no differences in TF interruptions, time to ≥80% nutritional delivery goal, or hypoglycemic episodes.

Conclusions:

This study demonstrated no clinically relevant differences in GV, insulin use, TF volume or caloric intake between BTF and CTF groups. Despite some shortcomings, our data suggest that providers should not feel limited to BTF or CTF because of concerns for GV, time to goal nutrition, insulin use, or caloric intake, and should consider other factors such as resource utilization, ease of administration, and/or institutional/patient characteristics.

Enteral Nutrition for Adults in the Hospital Setting

In patients unable to tolerate oral intake, multiple options of nutrient delivery are available to the clinician. Administration of enteral nutrition (EN) has long been considered the standard of care for nutrition support among patients unable to meet energy and protein requirements orally. Healthcare practitioners must make careful decisions related to ordering, administering, and monitoring EN therapy. In the hospital setting, the registered dietitian is a key resource in enteral formula selection and method of administration, monitoring for and troubleshooting EN-related complications, and transitioning to oral feeding. The hospital setting also presents many unique challenges in providing optimal nutrition to the enterally fed patient.

[Enteral nutrition therapy in critical care : Current knowledge, controversies, and practical implementation]

Nutrition therapy is a cornerstone in critical care. Early enteral feeding in patients who are unable to meet caloric requirements from oral intake is associated with better clinical outcomes. However, there are still uncertainties about optimal timing, dose, and formula selection of enteral nutrition in critically ill patients. In the present article, an overview of current knowledge and practical strategies for successful implementation of enteral nutrition in intensive care patients is given.

Definition, prevalence, and outcome of feeding intolerance in intensive care: a systematic review and meta-analysis

Clinicians and researchers frequently use the phrase 'feeding intolerance' (FI) as a descriptive term in enterally fed critically ill patients. We aimed to: (1) determine what is the most accepted definition of FI; (2) estimate the prevalence of FI; and (3) evaluate whether FI is associated with important outcomes. Systematic searches of peer-reviewed publications using PubMed, MEDLINE, and Web of Science were performed with studies reporting FI extracted. We identified 72 studies defining FI. In 33 studies, the definition was based on large gastric residual volumes (GRVs) together with other gastrointestinal symptoms, while 30 studies relied solely on large GRVs, six studies used inadequate delivery of enteral nutrition (EN) as a threshold, and three studies gastrointestinal symptoms without reference to GRV. The median volume used to define a 'large' GRV was 250 ml (ranges from 75 to 500 ml). The pooled proportion (n = 31 studies) of FI was 38.3% (95% CI 30.7-46.2). Five studies reported outcomes, all of them observed adverse outcome in FI patients. In three studies, respectively, FI was associated with increased mortality and ICU length-of-stay. In summary, FI is inconsistently defined but appears to occur frequently. There are preliminary data indicating that FI is associated with adverse outcomes. A standard definition of FI is required to determine the accuracy of these preliminary data.

Guideline clinical nutrition in patients with stroke

Stroke is regularly accompanied by dysphagia and other factors associated with decreased nutritional intake. Dysphagia with aspiration pneumonia and insufficient nutritional intake lead to worse outcome after stroke.

This guideline is the first chapter of the guideline “Clinical Nutrition in Neurology” of the German Society for Clinical Nutrition (DGEM) which itself is one part of a comprehensive guideline about all areas of Clinical Nutrition. The thirty-one recommendations of the guideline are based on a systematic literature search and review, last updated December 31, 2011. All recommendations were discussed and consented at several consensus conferences with the entire DGEM guideline group. The recommendations underline the importance of an early screening and assessment of dysphagia and give advice for an evidence based and comprehensive nutritional management to avoid aspiration, malnutrition and dehydration.

[Nutritional therapy in traumatic brain injury : Update 2012]

Severe traumatic brain injury ranks among the most common causes of death in young adults in western countries. Severe traumatic brain injury is typically followed by a pronounced pathophysiological cascade that accounts for many deaths. The aim of intensive care medicine after traumatic brain injury is to minimize and to control the consequences of this potentially fatal cascade. The avoidance of hypoxemia, arterial hypotension, intracranial hypertension, hyperthermia, hyperglycemia, hypoglycemia and thromboembolic complications is essential in preventing this cascade. The effect of nutrition has been rather underestimated as a means of improving the outcome after traumatic brain injury. Nutrition should be started within the first 24 h after trauma. Enteral, wherever applicable, should be the route of administration of nutrition. Enteral administration of the whole calculated calorie requirement on day 1 after trauma, if possible, lowers the infection and overall complication rates. The present review gives an update of a practical approach to nutrition in traumatic brain injury.

Effect of early nutritional support on intensive care unit length of stay and neurological status at discharge in children with severe traumatic brain injury

Pediatric severe traumatic brain injury treatment guidelines for nutrition indicate that "there are insufficient data to support a treatment guideline for this topic" (P. D. Adelson et al., 2003). Based on adult studies, the guideline provided an option for practitioners to start nutritional support within 72 hours of admission and full replacement by day 7. This retrospective, descriptive correlation study examined the timing of nutritional supplement initiation and the timing of achieving full caloric intake in relation to length of stay (LOS) in the intensive care unit (ICU) and patient disposition status at discharge from hospital in children 8-18 years old. Median time to initiation of nutrition was 1.5 days (0.02-11.9 days), and full caloric goals were achieved in 3.4 days (0.5-19.6 days). Median ICU LOS was 2.1 days (0.01-97.9 days). Overall, 48% of patients were discharged home; 28% experienced mild, moderate, or severe disability; and 24% either died or survived in a vegetative state. Early initiation and achieving full caloric intake were both positively correlated with shorter LOS in the ICU (p < .01, Spearman's rho correlational matrix) and better disposition status at discharge from the hospital (p < .05, Kruskal-Wallis test).

Current trends in critical care nutrition

Nutrition in the intensive care setting is a vital part of patient care, and may even be referred to as "nutritional therapy". Current nutritional practices have progressed a lot over the past few years, and draw from a large body of accumulating evidence. Yet, as with other trends in critical care, there are a lot of variations in the way nutrition is approached between institutions, as well as between individual physicians. This review attempts to look at some of these differences and provide recommendations based upon the available literature.

Early enteral nutrition and clinical outcomes of severe traumatic brain injury patients in acute stage: a multi-center cohort study

Guidelines for patients with severe traumatic brain injury (sTBI) published in 2007 recommend providing early nutrition after trauma. Early enteral nutrition (EN) started within 48 h post-injury reduces clinical malnutrition, prevents bacterial translocation from the gastrointestinal tract, and improves outcome in sTBI patients sustaining hypermetabolism and hypercatabolism. The aim of this study was to examine the effect of early EN support on survival rate, Glasgow Coma Scale (GCS) score, and clinical outcome of sTBI patients. Medical records of sTBI patients with GCS scores 4-8 were recruited from 18 hospitals in Taiwan, excluding patients with GCS scores ≤3. During 2002-2010, data from 145 EN patients receiving appropriate calories and nutrients within 48 h post-trauma were collected and compared with 152 non-EN controls matched for gender, age, body weight, initial GCS score, and operative status. The EN patients had a greater survival rate and GCS score on the 7th day in the intensive care unit (ICU), and a better outcome at 1 month post-injury. After adjusting for age, gender, initial GCS score, and recruitment period, the non-EN patients had a hazard ratio of 14.63 (95% CI 8.58-24.91) compared with EN patients. The GCS score during the first 7 ICU days was significantly improved among EN patients with GCS scores of 6-8 compared with EN patients with GCS scores of 4-5 and non-EN patients with GCS scores of 6-8. This finding demonstrates that EN within 48 h post-injury is associated with better survival, GCS recovery, and outcome among sTBI patients, particularly in those with a GCS score of 6-8.

Comparison of respiratory quotient and resting energy expenditure in two regimens of enteral feeding - continuous vs. intermittent in head-injured critically ill patients

INTRODUCTION

Measurement of respiratory quotient (RQ) and resting energy expenditure (REE) has been shown to be helpful in designing nutritional regimens. There is a paucity of the literature describing the impact of a feeding regimen on the energy expenditure patterns. Therefore, we studied the effect of continuous vs. intermittent feeding regimen in head-injured patients on mechanical ventilation on RQ and REE.

METHODS

After institutional ethical approval, this randomized study was conducted in 40 adult male patients with head injury requiring controlled mode of ventilation. Patients were randomly allocated into two groups. Group C: Feeds (30 kcal/kg/day) were given for 18 h/day, with night rest for 6 h. Group I: Six bolus feeds (30 kcal/kg/day) were given three hourly for 18 h with night rest for 6 h. RQ and REE were recorded every 30 min for 24 h. Blood sugar was measured 4 hourly. Other adverse effects such as feed intolerance, aspiration were noted.

RESULTS

Demographic profile and SOFA score were comparable in the two groups. Base line RQ (0.8 vs. 0.86) and REE (1527 vs. 1599 kcal/day) were comparable in both the groups (P>0.05). RQ was comparable in both groups during the study period at any time of the day (P>0.05). Base line RQ was compared with all other RQ values measured every half hour and fluctuation from the base line value was insignificant in both groups (P>0.05). REE was comparable in both the groups throughout the study period (P>0.5). Adequacy of feeding as assessed by EI/MREE was 105.7% and 105.3% in group C and group I, respectively. There was no significant difference in the blood sugar levels between the two groups (P>0.05).

CONCLUSION

We found from our study that RQ, REE, and blood sugar remain comparable with two regimens of enteral feeding - continuous vs. intermittent in neurosurgical patients on ventilator support in a ICU setup.

Gastrointestinal hemorrhage after acute ischemic stroke: an analysis of 607 cases

AIM: To analyze the incidence, diagnosis and treatment of gastrointestinal hemorrhage after acute ischemic stroke.

METHODS: A total of 607 patients with acute ischemic stroke were involved in the study. The relationship of Glasgow coma score, age, sex, diabetes, hypertension, smoking, and the type of cerebral infarction with the risk of gastrointestinal hemorrhage after acute ischemic stroke was analyzed.

RESULTS: Gastrointestinal bleeding was observed in 18 (2.9%) patients. The development of gastrointestinal hemorrhage after acute ischemic stroke was correlated with age (OR = 3.60) and middle cerebral artery infarction (MCA, OR = 9.47), but not with lacunar infarction, diabetes, hypertension, sex or smoking.

CONCLUSION: Elder age and larger MCA infarcts predict the development of gastrointestinal bleeding after acute ischemic stroke. Stroke mortality can be independently predicted by gastrointestinal bleeding.

Nutritional support in head injury

Nutritional support is imperative to the recovery of head-injury patients. Hypermetabolism and hypercatabolism place this patient population at increased risk for weight loss, muscle wasting, and malnutrition. Nutrition management may be further complicated by alterations in gastrointestinal motility. Resting energy expenditure should be measured using indirect calorimetry and protein status measured using urine urea nitrogen. Providing early enteral nutrition within 72 hours of injury may decrease infection rates and overall complications. Establishing standards of practice and nutrition protocols will assure patients receive optimal nutrition assessment and intervention in a timely manner.

Contemporary pharmacologic issues in the management of traumatic brain injury

Traumatic brain injury (TBI) is a major cause of death and disability in the United States. While there are no pharmacotherapeutic options currently available for attenuating the neurologic injury cascade after TBI, numerous pharmacologic issues are encountered in these critically ill patients. Adequate fluid resuscitation, reversal of coagulopathy, maintenance of cerebral perfusion, and treatment of intracranial hypertension are common interventions early in the treatment of TBI. Other deleterious complications such as venous thromboembolism, extremes in glucose concentrations, and stress-related mucosal disease should be anticipated and avoided. Early provision of nutrition and prevention of drug or alcohol withdrawal are also cornerstones of routine care in TBI patients. Prevention of infections and seizures may also be helpful. Clinicians caring for TBI patients should be familiar with the pharmacologic issues typical of this vulnerable population in order to develop optimal strategies of care to anticipate and prevent common complications.

Current and future therapeutic prokinetic therapy to improve enteral feed intolerance in the ICU patient

Malnutrition is associated with poor outcomes in critically ill patients, and providing enteral feeding to those who cannot eat is considered best practice. Enteral feeding is often unsuccessful when there is delayed gastric emptying. Recent research has given additional insight into the mechanisms underlying delayed gastric emptying. Pharmacological strategies to improve the success of feeding include prokinetic drugs such as metoclopramide and erythromycin alone or in combination. When drug treatment fails, either parenteral nutrition or direct small intestinal feeding is indicated. Simpler methods to access the duodenum and distal small bowel for feed delivery are under investigation. This review summarizes current understanding of the mechanisms underlying enteral feeding intolerance in critical illness, together with the evidence for current treatment practices. Areas requiring further research are also described.

Can continuous pump feeding reduce the incidence of pneumonia in nasogastric tube-fed patients? A randomized controlled trial

BACKGROUND & AIMS

Continuous pump feeding is often used to reduce aspiration risk in older patients on tube feeding, but its effectiveness in preventing aspiration pneumonia is unproven. A randomized controlled trial was therefore performed to examine the effectiveness of continuous pump feeding in decreasing the incidence of pneumonia in tube-fed older hospital patients.

METHODS

One hundred and seventy eight elderly patients from three convalescence hospitals and one infirmary, on nasogastric tube feeding, were randomly assigned to have intermittent bolus (bolus) or continuous pump (pump) feeding for 4weeks. The primary outcome was the incidence of pneumonia. The secondary outcome was mortality.

RESULTS

Eighty five subjects were randomized into the pump group and 93 in the bolus group. The groups were comparable in age, nutritional and functional status, co-morbidities and history of pneumonia, except that there were more women in the pump group. Within 4weeks, 15 subjects (17.6%) in the pump group and 18 (19.4%) in the bolus group developed pneumonia. Seven subjects (8.2%) in pump group and 13 subjects (14.0%) in bolus group died. There was no significant difference in either pneumonia or death rates between the two groups.

CONCLUSION

Continuous pump feeding did not significantly affect the rates of pneumonia or mortality in tube-fed older hospital patients when compared with intermittent bolus feeding.

Change in brain glucose after enteral nutrition in subarachnoid hemorrhage

BACKGROUND

The alteration of brain extracellular glucose after enteral nutrition (EN) remains unclear. In this study, we used brain microdialysis methods to estimate whether the physiologic elevation of plasma glucose following EN affects brain glucose metabolism of aneurysmal subarachnoid hemorrhage (SAH) patients.

METHODS

Brain extracellular glucose, lactate, glycerol, glutamate, and pyruvate were measured with a brain microdialysis probe in 12 patients (mean age: 60.0 y+/-7.8 y) after SAH. The EN was initially administered a mean of 3.2 d after the onset of SAH. All of the measured parameters were estimated before and after EN.

RESULTS

Cerebral perfusion pressure did not significantly change after SAH during the study period. Plasma glucose rose significantly after EN (141.4+/-11.6mg/dL before EN versus 183.8+/-26.2mg/dL immediately after EN (P=0.0006), 177.7+/-30.2mg/dL at 2h after EN (P=0.0033)). The brain extracellular glucose before EN (2.5+/-0.92mmol/L) was significantly lower than the levels measured just after (3.49+/-1.0mmol/L, P=0.0186) and 2h after the end of EN (3.70+/-1.0mmol/L, P=0.0053). Brain extracellular concentrations of lactate, glutamate, pyruvate, and glycerol showed no significant changes.

CONCLUSIONS

Brain extracellular glucose increased after the transient elevation of plasma glucose following EN. These results suggest that brief, physiologic elevations in plasma glucose after EN produced no changes in brain extracellular glutamate concentration or lactate/pyruvate ratio. These data may help determine the plasma glucose levels most effective for avoiding brain metabolic acidosis in patients after SAH. It remains unclear, however, how SAH itself influences these findings.

Bedside postpyloric feeding tube placement: a pilot series to validate this novel technique

OBJECTIVE

Postpyloric feeding may facilitate tolerance to enteral nutrition (EN) and offers an alternative route of feed administration when prepyloric EN fails. However, this is constrained by the difficulty of establishing nasojejunal (NJ) tube placement, which may necessitate endoscopy or radiology with the inevitable delay in the instigation of treatment. A bedside technique of NJ tube insertion has, therefore, been developed to permit blind postpyloric intubation. The primary aim of this audit was to validate the success of bedside NJ tube placement using the described technique. Secondary end points included the time taken to establish EN and the value of aspirate pH as an indicator of tube tip placement.

DESIGN

Observational.

SETTING

District general hospital.

PATIENTS

Consecutive patients requiring EN.

MEASUREMENTS AND MAIN RESULTS

The time taken to insert the tubes, the success rates in achieving the required position, and the time between the decision to feed and commencement of EN were recorded. The pH of any aspirate obtained was related to tube tip placement. Tube position was confirmed radiologically before starting EN. A total of 43 NJ tubes were inserted in 32 patients. Successful postpyloric intubation was achieved in 35 of 43 patients (81%). The median time for tube insertion was 18 (14-30) minutes. Time from the decision to feed to commencement of EN was 6 (5-18) hours. Aspirates were obtained from 26 of 43 (60%) intubations. Gastric aspirate pH readings were obtained for 19 of 43 (44%) of these intubations. Radiology reliably demonstrated the position of the tube tip in all cases.

CONCLUSIONS

By-the-bedside NJ tube placement is possible in more than 80% of patients. This may overcome delays in the commencement of feeds resulting from other methods of postpyloric tube placement. The use of aspirate pH on its own is not a reliable indicator of tube tip position.

Trauma

In terms of cost and years of potential lives lost, injury arguably remains the most important public health problem facing the United States. Care of traumatically injured patients depends on early surgical intervention and avoiding delays in the diagnosis of injuries that threaten life and limb. In the critical care phase, successful outcomes after injury depend almost solely on diligence, attention to detail, and surveillance for iatrogenic infections and complications.

Evaluation of Feeding Intolerance in Patients with Pentobarbital-Induced Coma

BACKGROUND:

There is considerable debate regarding the appropriateness of feeding patients by the enteral route in conjunction with pentobarbital coma therapy.

OBJECTIVE:

To determine the incidence of feeding intolerance (FI) in patients receiving pentobarbital in conjunction with enteral nutrition (EN).

METHODS:

A retrospective, observational evaluation of patients (>14 y of age) who received a therapeutic pentobarbital coma in combination with EN was conducted. Patients were divided into groups, based on the occurrence of FI defined as aspiration of gastric residuals greater than 75 mL for 2 consecutive measurements.

RESULTS:

Forty-eight percent (29 of 61) of patients experienced FI based on our definition. The median pentobarbital infusion rate did not differ significantly between patients who experienced FI versus those who did not (median [intraquartile range, IQR] 1.8 mg/kg/h [1.4, 2.1] vs 1.7 mg/kg/h [1.4, 2.5]; p = 0.680). The total pentobarbital bolus dose during the first 24 hours of therapy was lower in patients who experienced FI (700 mg [225, 980] vs 1000 mg [600, 1475]; p = 0.029). Median duration of pentobarbital therapy was comparable between groups (141.0 h [93.3, 217.3] vs 116.3 h [64.0, 174.8]; p = 0.115). Other factors with the potential to influence FI, such as catecholamines, neuromuscular blockade, and hyperglycemia, were similar between groups. The higher narcotic doses and greater percentage of patients receiving benzodiazepines in the FI group warrants further study.

CONCLUSIONS:

Pentobarbital therapy did not preclude use of EN in the entire study population. In addition, FI did not occur at a greater frequency in patients who received a higher dosage, a longer duration, or an earlier initiation of pentobarbital therapy.

Increased intestinal permeability in rats subjected to traumatic frontal lobe percussion brain injury

BACKGROUND

Dysfunction of the gastrointestinal tract is a common occurrence after traumatic brain injury (TBI). We hypothesized that increased intestinal permeability may result from a precisely controlled percussion injury to the exposed brains of anesthetized rats and that such an effect could be assessed in vitro using excised intestinal mucosae mounted in Ussing chambers.

METHODS

After craniotomy over the left medial prefrontal cortex on anesthetized rats, neurotrauma was produced using a pneumatically driven impactor on the exposed brain. Control rats were subjected to identical procedures but did not receive an impact. Muscle-stripped rat intestinal ileal and colonic segments were mounted in Ussing chambers within 30 minutes of death. Transepithelial electrical resistance (TEER) and the apparent permeability coefficient (Papp) of [C]-mannitol were recorded from intestinal tissue for 120 minutes. Histopathologic analysis was also performed to determine any gross morphologic changes in the intestine.

RESULTS

Ileal and colonic mucosae showed no differences in TEER in ileum or colon of TBI rats compared with controls. The Papp of mannitol was significantly increased in ilea from rats previously exposed to TBI compared with controls. Histologic analysis showed gross changes to 50% of the ileal but not the colonic sections from TBI rats.

CONCLUSION

TBI results in significantly reduced ileal barrier function, most likely mediated by open tight junctions. For patients with acute head injury, this may have implications for subsequent oral absorption of nutrients. Systemic delivery of luminal endotoxins may contribute to multiple organ failure.

Gastric emptying and the organization of antro-duodenal pressures in the critically ill

The motor dysfunctions underlying delayed gastric emptying (GE) in critical illness are poorly defined. Our aim was to characterize the relationship between antro-duodenal (AD) motility and GE in critically ill patients. AD pressures were recorded in 15 mechanically ventilated patients and 10 healthy volunteers for 2 h (i) during fasting, (ii) following an intragastric nutrient bolus with concurrent assessment of GE using the (13)C-octanoate breath test and (iii) during duodenal nutrient infusion. Propagated waves were characterized by length and direction of migration. Critical illness was associated with: (i) slower GE (GEC: 3.47 +/- 0.1 vs 2.99 +/- 0.2; P = 0.046), (ii) fewer antegrade (duodenal: 44%vs 83%, AD: 16%vs 83%; P < 0.001) and more retrograde (duodenal: 46%vs 12%, AD: 38%vs 4%; P < 0.001) waves, (iii) shorter wave propagation (duodenal: 4.7 +/- 0.3 vs 6.0 +/- 0.4 cm; AD: 7.7 +/- 0.6 vs 10.9 +/- 0.9 cm; P = 0.004) and (iv) a close correlation between GE with the percentage of propagated phase 3 waves that were antegrade (r = 0.914, P = 0.03) and retrograde (r = -0.95, P = 0.014). In critical illness, the organization of AD pressure waves is abnormal and associated with slow GE.