Nutrition in Clinical Practice

Intestinal failure is a condition in which inadequate digestion or absorption of fluid, electrolytes, and nutrients leads to dehydration or malnutrition. The most common cause of intestinal failure is short bowel syndrome (SBS) defined as <200 cm of functional small intestine. SBS may result from congenital abnormalities or from surgical resection. For the past 3 decades, patients with severe SBS were managed with home parenteral nutrition (HPN). With the emergence of new therapies, the clinician now has multiple options to treat these patients. These include intestinal rehabilitation regimens whereby patients are treated with specialized oral diets, soluble fiber, oral rehydration solutions (ORS), and trophic factors to enhance absorption. There are also a variety of surgical techniques available to preserve intestinal length. Small bowel and multivisceral transplantation has evolved during the last decade to be a valid therapeutic option for those patients who cannot be rehabilitated or who fail HPN. These are interrelated services designed to offer the patient the best therapeutic options to meet their individual needs. This article reviews the principles associated with the nutrition management of this very complex and diverse group of patients.

Extensive resection of the intestinal tract with resulting malabsorption is known as short bowel syndrome (SBS). Adaptation and rehabilitation of the remaining small bowel occurs spontaneously after resection and can be enhanced by diet, medications, and use of intestinal trophic factors such as recombinant human growth hormone (r-hGH). Many trials have been published on the influence of r-hGH therapy in SBS patients, with varying results. Analysis of the trials has produced a set of criteria that can be used to define the patient most likely to benefit from r-hGH therapy.

Nutrition therapy after small bowel or combined liver/small bowel transplantation is challenging. The objective is to restore enteral autonomy to a patient with a complex past surgical history and equally complex posttransplant immunosuppressive regimen in the context of a newly created surgical anatomy. Improved surgical techniques and immunosuppressive regimens have led to superior outcomes. Accompanying these advances is a range of nutrition issues that require specific management strategies. This review outlines the current clinical practice and decision making used to create individualized nutrition regimens for small bowel or combined liver/small bowel transplant recipients. Successful small bowel transplant outcomes require a coordinated effort from a transplant team to restore nutritional autonomy to transplant recipients and free them from parenteral nutrition.

Anatomic and physiologic changes introduced by gastric surgery result in clinically significant dumping syndrome in approximately 10% of patients. Dumping is the effect of alteration in the motor functions of the stomach, including disturbances in the gastric reservoir and transporting function. Gastrointestinal hormones play an important role in dumping by mediating responses to surgical resection. Treatment options of dumping syndrome include diet, medications, and surgical revision. Poor nutrition status can be anticipated in patients who fail conservative therapy. Management of refractory dumping syndrome can be a challenge. This review highlights current knowledge about the mechanisms of dumping syndrome and available therapy.

Foods that account for 90% of allergic reactions in children are cow's milk protein, eggs, peanut, soy, tree nuts, fish, and wheat. Food allergy can manifest as urticaria/angioedema, anaphylaxis, atopic dermatitis, respiratory symptoms, or a gastrointestinal (GI) disorder. GI allergic manifestations can be classified as immunoglobulin E (IgE) mediated (immediate GI hypersensitivity and oral allergy syndrome); “mixed” GI allergy syndromes (involving some IgE components and some non-IgE or T-cell-mediated components) include eosinophilic esophagitis and eosinophilic gastroenteritis. Non-IgE-mediated or T-cell-mediated allergic GI disorders include dietary protein enteropathy, protein-induced enterocolitis, and proctitis. All these conditions share a common denominator: the response of the immune system to a specific protein leading to pathologic inflammatory changes in the GI tract. This immunological response can elicit symptoms such as diarrhea, vomiting, dysphagia, constipation, or GI blood loss, symptoms consistent with a GI disorder. The detection of food allergies can be accomplished by the use of radioallergosorbent (RAST) testing and skin prick tests in helping to assess the IgE-mediated disorders. Patch tests may help evaluate delayed hypersensitivity reactions. Treatment of GI allergic disorders ranges from strict dietary elimination of offending food(s), use of protein hydrolysates, and use of l-amino acid–based formula when protein hydrolysates fail. Treatment with topical (for eosinophilic esophagitis) or systemic steroids is used if all dietary measures are unsuccessful. Maternal breast feeding or the use from birth of hydrolysate formulas (extensive or partial hydrolysates) may be efficacious in the prevention of atopic disease in “high-risk” families (with at least 1 parent or sibling with a history of atopic disease).

Constipation is a common complaint in childhood, and the etiology of many healthcare referrals. Despite literature documenting the high frequency of this problem, there is little research directly relating the food consumed and the eventual stool consistency. There is literature suggesting the importance of adequate fiber intake in children to maintain soft stools. Other dietary modifications actually have not been shown to be helpful or are not based on actual clinical studies. The presence of dietary allergies may also contribute to etiology of constipation. More studies to provide further linkages between diet and constipation are clearly needed.

Patients with upper gastrointestinal cancer or other surgical diseases are at high risk for both mechanical and infectious complications. The disease process itself places these patients at increased risk for malnutrition, with subsequent postoperative complications. Because these surgeries are semielective, a period of time is available to optimize the patient's condition. There are several trials that suggest preoperative immunonutrition supplementation improves outcomes and is cost-effective by reducing complications. However, the most important choice a patient or clinician can make may well be by whom and where the surgery is performed.

Whether to provide artificial enteral nutrition therapy to a patient with evidence of gastrointestinal bleeding (GIB) creates a difficult clinical dilemma. Concern that enteral feeding may contribute to the morbidity associated with GIB leads to delays in initiating enteral therapy or to cessation of feeding in the patient in whom artificial nutrition support has already been started. Surprisingly, evidence of GIB is not an automatic contraindication to further enteral feeding. Depending on the etiology of the GIB, enteral nutrition may protect the gut mucosa and reduce further bleeding in some patients, actually increase risk for rebleeding in other patients, or serve as a moot point with no relation to further bleeding or morbidity in still other patients. In many cases, an endoscopic evaluation is needed to distinguish the differential etiology of the GIB. The nutrition support specialist needs a full understanding of the physiology behind the varying diagnoses for GIB to know whether feedings can be initiated or continued or whether enteral feedings need to be withheld for 48–72 hours until risk for rebleeding and further morbidity is minimized.

After massive small-intestinal resection or combined small-intestinal and colonic resection, diarrhea with resulting dehydration, electrolyte abnormalities, and malnutrition occur. Many patients become dependent on IV fluids and nutrition. An adaptation process manifested clinically by decreased diarrhea and improved nutrient absorption according to decreased parenteral nutrition and fluid requirements has been noted to occur over time. In some patients, adaptation is inadequate and may require special techniques to enhance and augment this process. This is a case of a 52-year-old woman who experienced increased stoma output 1 week after major intestinal resection, resulting in dehydration. She required IV fluids in order to maintain hydration. After the initiation of an intestinal rehabilitation program, which included modified diet, soluble fiber, oral rehydration solution (ORS), and medications, IV fluids were successfully weaned off in 3 months. She continues not to receive IV fluids and continues to follow the intestinal rehabilitation plan.

There is a high prevalence of protein-energy malnutrition (PEM) in chronic dialysis patients. Causes of PEM include the catabolic effects of hemodialysis treatments, acidemia associated with end-stage renal disease, common comorbid conditions, and uremia-induced anorexia. Morbidity and mortality increase with PEM. Before considering parenteral nutrition (PN) as a nutrition intervention in a maintenance dialysis patient, all other efforts to promote optimal nutrition need to be exhausted. The first step is careful evaluation of protein-energy status, followed by intensive nutrition counseling. If necessary, this is followed by oral nutrition supplementation, appetite stimulation, enteral tube feedings, and finally PN.

Short-term parenteral nutrition (PN) became a crucial component of the management of a 38-year-old hemodialysis (HD) patient who endured serious complications after kidney transplant rejection. A profound and prolonged malnourished state followed her treatment for necrotizing pancreatitis. She had developed persistent hypercalcemia believed secondary to tertiary hyperparathyroidism (HPT) and immobilization. Later, she developed hungry bone syndrome (HBS) after parathyroidectomy (PTX). She also developed refeeding syndrome after initiation of PN. The patient's persistent, poorly understood hypercalcemia did not resolve even after PTX and removal of all other sources of vitamin D and calcium from her feedings, medications, and dialysis bath. The close communication of the inpatient and outpatient dialysis multidisciplinary teams became a key component to the successful outcome in this complex patient.

Background: The purpose of this study was to provide a detailed evaluation of adherence to nutrition supplements by patients with a lower limb fracture. Methods: These descriptive data are from 49 nutritionally“ at-risk” patients aged 70+ years admitted to the hospital after a fall-related lower limb fracture and allocated to receive supplementation as part of a randomized, controlled trial. Supplementation commenced on day 7 and continued for 42 days. Prescribed volumes aimed to meet 45% of individually estimated theoretical energy requirements to meet the shortfall between literature estimates of energy intake and requirements. The supplement was administered by nursing staff on medication rounds in the acute or residential care settings and supervised through thrice-weekly home visits postdischarge. Results: Median daily percent of the prescribed volume of nutrition supplement consumed averaged over the 42 days was 67% (interquartile range [IQR], 31–89, n = 49). There was no difference in adherence for gender, accommodation, cognition, or whether the supplement was self-administered or supervised. Twenty-three participants took some supplement every day, and a further 12 missed <5 days. For these 35 “nonrefusers,” adherence was 82% (IQR, 65–93), and they lost on average 0.7% (SD, 4.0%) of baseline weight over the 6 weeks of supplementation compared with a loss of 5.5% (SD, 5.4%) in the “refusers” (n = 14, 29%), p = .003. Conclusions: We achieved better volume and energy consumption than previous studies of hip fracture patients but still failed to meet target supplement volumes prescribed to meet 45% of theoretical energy requirements. Clinicians should consider alternative methods of feeding such as a nasogastric tube, particularly in those patients where adherence to oral nutrition supplements is poor and dietary intake alone is insufficient to meet estimated energy requirements.