Nutrition in Clinical Practice

Provision of enteral nutrition (EN) to critically ill patients early upon admission to the intensive care unit exerts a beneficial physiologic effect that downregulates systemic immune responses, reduces oxidative stress, and improves patient outcome. Adding specific pharmaconutrient agents to EN in certain patient populations has a synergistic effect, magnifying the degree of this favorable physiologic response. In contrast, failure to provide enteral nutrients creates a physiologic profile that exacerbates oxidative stress and increases the systemic inflammatory response syndrome. Unfortunately, parenteral nutrition (PN) in the form and manner currently provided in North America does not appear to mimic the same physiologic response seen with EN. In the future, use of alternative fuel sources, steps to promote better tolerance of EN, and innovative strategies for delivery of both EN and PN may serve to further enhance the physiologic effect of nutrition therapy and to achieve even greater improvement in patient outcome.

Those who read the medical literature should understand the principles of evidence-based medicine. Even randomized trials can contain design or interpretative flaws that allow bias to produce, or exaggerate the size of, beneficial effects. Such problems beset the literature of enteral nutrition (EN). Investigators who have compared EN with parenteral nutrition (PN) have alleged that EN produces fewer adverse events, but such studies do not assess the absolute value of either therapy, and data exist suggesting that PN causes net harm. Trials comparing EN with no nutrition therapy have not yielded convincing evidence of efficacy because the study designs have failed to use methods to prevent bias from interfering with the observations. This same problem exists with trials that have assessed volitional feeding programs (eg, oral supplements). Thus, although systematic reviews have alleged that EN benefits patients undergoing surgery, patients in the critical care unit, patients with liver disease, and patients with pancreatitis, the presence of bias limits any positive conclusions. As a manifestation of this issue, when the various trials are separated into studies with high and low risks of bias, those with low risks have not shown any benefit. EN has been accepted and implemented despite the lack of convincing scientific support of efficacy.

Enteral misconnections are defined as inadvertent connections between enteral feeding systems and nonenteral systems such as intravascular lines, peritoneal dialysis catheters, tracheostomy tube cuffs, medical gas tubing, and so on. Sentinel event data and causative factors are outlined along with potential solutions to prevent such medical errors. The solutions can be grouped into 3 areas: (1) education, awareness, and human factors; (2) purchasing strategies; and (3) design changes. Updates on safety innovations and programs are presented.

In developing the evidence-based Enteral Nutrition Practice Recommendations, the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) formed a task force to address the many aspects of safety in the delivery and provision of enteral nutrition support. This recently published document provides healthcare professionals with recommendations that are derived from evidence-based practice. The development and use of clinical practice guidelines (CPGs) is a recent, significant contribution for the dissemination of evidence-based medicine. This involves the review of scientific literature along with clinical skill and knowledge to generate specific recommendations assisting healthcare providers and patients with decisions regarding appropriate healthcare. A primary opportunity to improve patient outcomes will come from the effective delivery of existing therapies rather than from the new development of treatment modalities. Compliance with CPGs is challenging because it depends on a variety of factors. Both general and specific strategies have been devised with the expansion of the new discipline of implementation science. The high degree of evidence now available in medicine gives clinicians more opportunity to improve patient outcomes and quality of care. It remains for clinicians to evaluate their institutional mission and goals, and to investigate those CPGs appropriate to improve patient care in that setting.

In the last few decades, there has been tremendous advancement in the area of enteral nutrition formulas. Enteral nutrition makes it possible to provide important substrates for those who cannot or will not meet daily requirements via oral intake but who have an intact digestive system. Numerous enteral nutrition formulas are currently available, with a large portion of them targeting specific disease conditions, thus making it a daunting task at times for a clinician to sort through all the possibilities and decide on the most appropriate formula. This review provides a close examination of various enteral formula categories and presents proposed mechanisms of specialized ingredients, followed by a thorough evidence-based analysis of existing literature before making recommendations for the various enteral formula categories.

Because every child has individual needs, there are a variety of infant and pediatric formulas from which to choose. Not only are there several categories of formulas including milk protein-based, soy protein-based, hydrolyzed protein, and amino acid-based, but there are differences between products within each category. Research is being done in the area of formula design for the prevention or treatment of disease. In this article, the authors review types of formulas and their indications for use for infants and children, and review current literature on formula trends.

The delivery of a preterm baby is a nutrition emergency. Growth and the accumulation of nutrient reserves are higher during the third trimester of pregnancy than at any other time during the life cycle. Enteral nutrition is the preferred mode of support and human milk the preferred source of enteral nutrition. Human milk is highly digestible and contains many anti-infective components, which confer a lower risk of infection. The mother of a preterm infant requires education, equipment, and encouragement to successfully initiate and sustain lactation. Human milk requires nutrient fortification to meet the protein and mineral needs of the rapidly growing preterm infant. Commercial human milk fortifiers are available. If human milk is unavailable or the volume is insufficient, preterm formulas are available. Preterm formulas have different sources of macronutrients and greater density of all nutrients than formulas intended for term newborns. Preterm infants benefit from early enteral feedings with slow but steady increases in feedings to achieve full support. Infants born at <35 weeks gestational age are supported with tube feedings. A transition to feedings at the breast or to bottle feedings is gradually made as the baby matures. Nutrient recommendations specific to the preterm infant are available. Special products and feeding strategies exist to respond to common medical conditions that can complicate nutrition management. Optimal nutrition care of the preterm infant offers the opportunity to improve outcomes for children.

The pediatric intensive care unit (PICU) environment poses unique challenges to achieving enteral nutrition (EN) goals for the critically ill child. Nutrition support in the PICU is often in conflict with the complexity of care provided to acutely ill children. A significant proportion of eligible patients do not receive optimal enteral nutrition for avoidable reasons. Early institution of EN is recommended and the gastric route is preferred because of ease of administration and reduced costs compared with the transpyloric route. In patients with poor gastric emptying or in cases where a trial of gastric feeding has failed, transpyloric or postpyloric feeding may be used to decrease the risk of aspiration and to improve enteral feed tolerance. However, there is no evidence of benefit for routine use of small bowel feeding in all patients admitted to the PICU. The placement of blind nasoenteric feeding tubes can be technically challenging, is not without complications, and requires local expertise and experience for successful placement and maintenance. A protocolized approach to selecting the optimal route and advancing enteral feedings may optimize EN delivery. Institutional practice guidelines based on consensus, available evidence, and national guidelines may decrease time to reaching caloric goal, improve protein balance, and potentially affect clinical outcomes. The rationale and challenges to the delivery and maintenance of optimal EN, and strategies to achieve optimal EN during critical illness, are discussed.

Objective: To determine whether nutritional supplementation following hospital discharge in patients who undergo gastrointestinal (GI) surgery is benefical in specific outcome measures. Methods: A systematic review was conducted of randomized controlled trials comparing nutritional supplements vs a “standard care” regimen given to patients following discharge from hospital after GI surgery. Outcome measures were weight change, quality of life, clinical complications, fatigue, and hand grip strength. Results: Four studies were identified. Postdischarge oral nutritional supplements were found to be safe and increased energy intake, protein intake, and weight in patients after discharge from hospital. The greatest gains in weight were seen in malnourished patients. Little evidence was found that nutritional supplements reduce morbidity or improve quality of life, fatigue, or hand-grip strength. Only one study was methodologically adequate, and none were powered to detect differences in clinical complications. Conclusions: In patients who undergo GI surgery and receive nutritional supplements after discharge from hospital, little evidence of clinical benefit was found, principally through lack of robust data. All the studies were under-powered or not specifically designed to show benefit during this period. It is recommended that nutritional supplements be offered to malnourished patients or those at high risk of poor dietary intake at discharge from hospital.

The risk for disordered oropharyngeal swallowing (dysphagia) increases with age. Loss of swallowing function can have devastating health implications, including dehydration, malnutrition, pneumonia, and reduced quality of life. Age-related changes increase risk for dysphagia. First, natural, healthy aging takes its toll on head and neck anatomy and physiologic and neural mechanisms underpinning swallowing function. This progression of change contributes to alterations in the swallowing in healthy older adults and is termed presbyphagia, naturally diminishing functional reserve. Second, disease prevalence increases with age, and dysphagia is a comorbidity of many age-related diseases and/or their treatments. Sensory changes, medication, sarcopenia, and age-related diseases are discussed herein. Recent findings that health complications are associated with dysphagia are presented. Nutrient requirements, fluid intake, and nutrition assessment for older adults are reviewed relative to dysphagia. Dysphagia screening and the pros and cons of tube feeding as a solution are discussed. Optimal intervention strategies for elders with dysphagia ranging from compensatory interventions to more rigorous exercise approaches are presented. Compelling evidence of improved functional swallowing and eating outcomes resulting from active rehabilitation focusing on increasing strength of head and neck musculature is provided. In summary, although oropharyngeal dysphagia may be life threatening, so are some of the traditional alternatives, particularly for frail, elderly patients. Although the state of the evidence calls for more research, this review indicates that the behavioral, dietary, and environmental modifications emerging in this past decade are compassionate, promising, and, in many cases, preferred alternatives to the always present option of tube feeding.

Background: Dysphagia and aspiration occur frequently in stroke patients. The aim of the present study was to evaluate 2 consistencies (liquid and spoon-thick/pudding-like) regarding the risk of aspiration and to determine the usefulness of a bedside speech therapy assessment to predict risk of aspiration. Methods: This randomized, crossover clinical trial was carried out April to August 2001 at a university hospital. Sixty-one inpatients diagnosed with acute phase or prior stroke received liquid and spoon-thick (pudding-like) feeds during nasoendoscopy and bedside clinical assessment. Results: Aspiration occured in only 3 patients with the spoon-thick consistency vs 21 with the liquid consistency (relative risk = 0.13; 95% confidence interval = 0.04-0.39; P < .001). The bedside assessment had a sensitivity of 81% and a specificity of 70.8% to detect risk of aspiration. Conclusions: The use of a spoon-thick consistency reduced the risk of aspiration compared with the liquid consistency. Clinical assessment was useful to predict aspiration, although the probability of dysphagia in the presence of a negative clinical assessment (29%) is a reason for concern.

Background: Despite the increasing use of Rouxen-Y gastric bypass (RYGBP) in the treatment of morbid obesity, data about postoperative nutritional deficiencies and their treatment remain scarce. Objective: The aim of this study was to evaluate the efficacy of a standard multivitamin preparation in the prevention and treatment of nutritional deficiencies in obese patients after RYGBP. Design: This was a retrospective study of a 2-year follow-up of obese patients after RYGBP surgery. Between the first and the sixth postoperative months, a standardized multivitamin preparation was prescribed for all patients. Specific requirements for additional substitutive treatments were systematically assessed by a biologic workup at 3, 6, 9, 12, 18, and 24 months. Results: A total of 137 morbidly obese patients (110 women and 27 men) were included. The mean (±SD) age at the time of surgery was 39.9± 10.0 years, and the body mass index (in kg/m²) was 46.7± 6.5. Three months after RYGBP, 34% of these patients required at least one specific supplement in addition to the multivitamin preparation. At 6 and 24 months, this proportion increased to 59% and 98%, respectively. Two years after RYGBP, a mean amount of 2.9 ± 1.4 specific supplements had been prescribed for each patient, including vitamin B-12, iron, calcium + vitamin D, and folic acid. At that time, the mean monthly cost of the substitutive treatment was $34.83. Conclusion: Nutritional deficiencies are very common after RYGBP and occur despite supplementation with the standard multivitamin preparation. Therefore, careful postoperative follow-up is indicated to detect and treat those deficiencies. (Am J Clin Nutr. 2008;87:1128-33.)

Gasteyger C, Suter M, Gaillard RC, and Giusti V.