AGA technical review on parenteral nutrition.

This literature review and the recommendations therein were prepared for the American Gastroenterological Association Clinical Practice and Practice Economics Committee. The paper was approved by the Committee on September 13, 2001, and by the AGA Governing Board on May 18, 2001.

Nutrition in gastroenterology and hepatology.

Nutritional issues, sometimes obvious and sometimes not so obvious, confront the primary care practitioner on a daily basis. Understanding the multi-disciplinary nature of nutrition science and clinical nutrition and having a basic understanding of gastrointestinal tract digestive and absorptive physiology can only help sort out the many issues involved. The general practitioner needs a core understanding of the principles of nutrition assessment.

Evolving management and outcome of esophageal cancer with airway involvement.

BACKGROUND: Esophageal cancer with airway involvement, including patients with esophagorespiratory fistula (ERF), has been associated with a poor prognosis. Multimodality treatment, self-expanding metal stents, and improved supportive therapy may be impacting outcome in these patients. There is concern for the development of ERF during therapy. METHODS: We retrospectively studied 74 consecutive male patients at a single institution presenting between 1/85 to 12/98 with bronchoscopic, endoscopic or radiographic confirmation of airway involvement with esophageal cancer, including 35 patients with ERF. Comparison was made between the first 35 patients (group I) and the last 39 patients (group II) with regard to antineoplastic therapy, stent placement, and survival. RESULTS: Treatment in group I included supportive care in 17 of 35 patients, plastic stent in 7 of 35 patients, and radiation or chemotherapy in 9 of 35 patients. In group II, radiation or chemotherapy was offered to 33 patients, and self-expanding metal stents were placed in 10 of 39 patients. Surgical resection was possible after neoadjuvant therapy in 13 of 39 patients in group II, including 2 initially presenting with ERF. Median survival in group I was 16 weeks and in group II was 37 weeks. Comparison of Kaplan-Meier survival estimates using log rank testing demonstrated improved survival in group II (p = 0.0026). Long-term survival in 4 group II patients initially presenting with ERF and receiving multimodality treatment was observed. Development of ERF during treatment occurred in 3 group II patients. Treatment failure was predominantly local in group I and local and distant in group II. CONCLUSIONS: More aggressive treatment may favorably influence outcome in esophageal cancer with airway invasion. Long-term survival and the development of ERF during therapy occurred at similar rates.

Home artificial nutrition.

Home artificial nutrition is a mature technology that has been with us for over a quarter of a century. Its use appears to be more widespread in the USA than in other western countries. Issues of outcome, ethics, and quality of life are increasingly important. Complications continue to be reported, some newly recognized and some that we must continually relearn.

Systematic screening of chromosome 18 for loss of heterozygosity in esophageal squamous cell carcinoma.

Esophageal cancer ranks among the 10 most common cancers in the world, and is almost uniformly fatal. The genetic events leading to the development of esophageal carcinoma are not well established. To identify genomic regions involved in esophageal carcinogenesis, we performed a systematic screening for loss of heterozygosity (LOH) in 24 samples of squamous cell carcinomas, initially focusing the analysis on chromosome 18. Thirteen short tandem repeat markers spanning 18p and 18q were used. We found a broad peak of LOH spanning 18p11.2 and 18q21.1 with the most frequent LOH (72%) at D18S978 on 18q12.2, which coincides with a known fragile site FRA18A. This region is 4 cM proximal to known tumor suppressor genes and therefore suggests the possible existence of a yet undiscovered tumor suppressor gene.

Grains or veins: is enteral nutrition really better than parenteral nutrition? A look at the evidence.

BACKGROUND: Enteral nutrition is said to be better than parenteral nutrition for providing nutrition support to humans. PURPOSE: To assess the literature documenting the assertions that enteral nutrition is superior to parenteral nutrition with respect to cost, safety, physiology, intestinal structure and function, bacterial translocation, and outcome. DATA IDENTIFICATION: Sources included MEDLINE search, personal files, and references from human comparative studies of enteral vs parenteral nutrition. STUDY SELECTION: The goal was to include all human studies directly addressing questions of comparative efficacy of enteral and parenteral nutrition. Emphasis was given to prospective randomized controlled studies where available. Retrospective comparisons were not included. DATA EXTRACTION: An attempt was made to briefly summarize methodology and findings of relevant studies. No general attempt was made to assess quality of individual studies. RESULTS OF DATA SYNTHESIS: Enteral nutrition appears to be less expensive than parenteral nutrition, but new economic analyses are needed given the newer aggressive access techniques for enteral nutrition. Enteral nutrition is associated with meaningful morbidity and mortality. The little comparative data existent suggest no differences in safety. Comparative studies of physiology and metabolism as well as comparative and noncomparative studies of intestinal function and structure do not support putative advantages of enteral nutrition. There is no evidence that enteral nutrition prevents bacterial translocation in humans. Enteral nutrition probably reduces septic morbidity compared with parenteral nutrition in abdominal trauma. Otherwise, there is no evidence that enteral nutrition consistently improves patient outcome compared with parenteral nutrition. CONCLUSIONS: With the exception of decreased cost and probable reduced septic morbidity in acute abdominal trauma, the available literature does not support the thesis that enteral nutrition is better than parenteral nutrition in humans.

Group I: choosing the appropriate method of placement of an enteral feeding tube in the high-risk population.

The traditional nasogastric/nasoenteric feeding tube is the preferred access device for short-term feeding (< 30 days), with delivery into the stomach suggested unless aspiration or motility abnormalities are present. Preference for a long-term access device is operator- and facility-dependent. Endoscopic or fluoroscopic placement is preferred as first choices over laparoscopic placement because of considerations of cost, need for general anesthesia, and need for operating room time. Gastrostomy is preferred over intestinal placement for long-term access unless problems with aspiration or motility abnormalities exist.

Hepatobiliary toxicity of total parenteral nutrition in adults.

The enzymology and clinical manifestations of total parenteral nutrition (TPN)-induced liver abnormalities have been investigated extensively. The cause, pathogenesis, and treatment of TPN-related hepatic and biliary dysfunction in adults still are not well understood, however. The findings of experimental studies in animals has not necessarily correlated with the human data, and there have been few prospective, randomized controlled trials examining the mechanism, cause, or treatment of TPN-induced hepatobiliary toxicity in adults. This article examines the animal models of pathogenesis and treatment of TPN-induced intrahepatic and extrahepatic abnormalities, and provides a discussion of abnormalities seen in humans.

Bacterial translocation and enteral nutrition in humans: an outsider looks in.

PURPOSE: To assess the literature documenting the existence of bacterial translocation in humans, the effects of enteral nutrition on bacterial translocation in humans, and the hypothesis that enteral nutrition prevents bacterial translocation in humans. DATA IDENTIFICATION: Sources included Medline search, references from review articles, and references from animal and human studies. STUDY SELECTION: The goal was to include all animal and human studies directly addressing questions of bacterial translocation and nutritional status or nutritional support. DATA EXTRACTION: An attempt was made to briefly summarize methodology and findings of relevent studies. No general attempt was made to assess quality of individual studies. RESULTS OF DATA SYNTHESIS: Bacterial translocation is a well documented phenomenon in animal models. Starvation and malnutrition of themselves do not induce bacterial translocation, but may facilitate translocation in the presence of other systemic insults. Parenteral nutrition and many forms of enteral nutrition may induce and/or facilitate bacterial translocation. Chow and certain fiber sources seem protective. Moderate direct and several lines of indirect evidence support the existence of bacterial translocation in humans. There is no direct evidence and questionable indirect evidence suggesting that enteral nutrition prevents or modifies bacterial translocation in humans. CONCLUSIONS: The hypothesis relating enteral nutrition and bacterial translocation in critically ill patients remains attractive, but unproven.

Clinical trials of nutritional support in cancer. Parenteral and enteral therapy.

Cancer-related malnutrition is associated with poor prognosis. Although logic would dictate that nutritional support should improve malnutrition and thus outcome, when tested by controlled clinical trials, this has not borne out. With the exception of bone marrow transplantation, routine specialized nutritional support, particularly parenteral nutrition, has not demonstrated consistent therapeutic benefit with respect to any outcome measure and may be associated with harm to patients. The clinician must carefully select appropriate indications for specialized nutritional support in cancer patients.

Efficacy and safety of total parenteral nutrition.

Total parenteral nutrition has been widely available for almost 20 years. This therapy can demonstrably support growth in neonates and children and will maintain life in adults with an inadequate intestine. It may be beneficial in highly selected preoperative patients, and patients with head trauma. Otherwise, its role in specific disease states or pathologic conditions remains unclear. Whether its benefits outweigh its hazards is largely unknown. Crucial to the decision-making process for initiation of TPN is a knowledge of when starvation becomes detrimental to an individual and whether TPN can prevent or reverse any of starvation's detrimental effects; this information is unknown. Many potential complications exist, the frequency of which generally is dependent on the expertise of the user. Nutritional support teams appear to reduce septic, mechanical, and metabolic complications and may improve the clinical efficacy and decrease the cost of TPN care.

Vitamin prescriptions on a hospital general medical ward: result of a drug utilization review.

Records of 103 consecutive admissions to a general medical ward over 4 months in a Veterans Administration Medical Center were reviewed. Assessment was made of nutritional status and potential need for supplemental vitamin therapy based upon predetermined criteria. Thirty-five of the 103 patients received one or more vitamin supplements. No patient received unnecessary vitamins as defined by our criteria. However, 48 patients had indications for vitamin supplementation, but did not receive any. Analysis of data by indication for vitamin therapy revealed 125 indications for vitamin therapy in 83 patients. Of the 125 indications 54 were treated appropriately, but there were no vitamin prescriptions in 71 indicated instances. We conclude that indicated vitamin supplementation may be underutilized in hospitalized general medical patients.

Central venous catheter care in parenteral nutrition: a review.

Central venous catheter care in parenteral nutrition has been described in numerous publications. These descriptions include care of both short- and long-term catheters. Important aspects in the prevention of infection in central venous catheters used for parenteral nutrition have included: the method of central venous access, subcutaneous tunneling, dressing change techniques, therapeutic uses of the catheter, and catheter-intravenous tubing connection care. Methods of predicting infection and evaluating catheter sepsis have been described. The efficacy of intervention by specialized nutrition support teams in infection control related to these catheters has been demonstrated. Newer partially implantable and completely implantable venous access devices have been used for parenteral nutrition. Methods of infection control and prevention of mechanical damage of these types of catheters have been examined with various results. Care and composition of central venous catheters have been shown to have some role in thrombus formation in the central veins. The use of heparin to prevent thrombosis and catheter occlusion, and the varying degrees of success obtained, have been described. Medical treatment of the occluded catheter with urokinase may be a necessary alternative to discontinuance of that catheter. Overall consideration of research methods used to reach conclusions for catheter care should be considered in the evaluation of appropriate care in each situation.