Enteral nutrition support: formula preparation from modular ingredients

Many hospitalized patients are undernourished, and often this condition can be corrected by feeding one of a variety of commercial enteral formulas through a thin nasoenteral cannula. In a subset of tube feeding patients, nutritional requirements are unique, and needs cannot be met by a fixed composition formula. Modification, or de novo fabrication of the enteral formula is therefore required. Few reviews have adequately addressed some of the complexities of designing, mixing, and feeding these specialized diets. This report provides some of this information, and shows that considerably more education and research in this area is needed.     

Effect of liquid pancreatic enzymes on the assimilation of fat in different liquid formula diets

BACKGROUND: In some diseases, patients require high-calorie tube feeding with standard enteral formulas usually administered via temporal feeding tubes. One frequent pathophysiological condition in a relevant number of these patients is exocrine pancreatic insufficiency. Patients unable to swallow capsules might benefit from a liquid pancreatic enzyme (LPE) preparation. METHODS: LPEs were prepared and mixed with different commercially available formula diets produced for enteral feeding. Lipolysis was then measured by fatty acid titration. RESULTS: Complete lipolysis by liquid enzyme preparations was observed in diverse formula diets. Fat assimilation was even complete when LPE had been prepared 3.5 hours before the experiments, showing that the enzymes had been stable up to that time. CONCLUSIONS: The use of LPEs seems to be a good therapeutic option in patients with exocrine pancreatic insufficiency and the need for permanent high-calorie enteral feeding. Pharmaceutical companies should therefore be further encouraged to develop and distribute liquid enzyme preparations.     

Does the supplementation of the formula with fibre increase the risk of gastro-oesophageal reflux during enteral nutrition? A human study

BACKGROUND & AIMS: Fibre-supplements in enteral feeding could increase the risk of gastro-oesophageal reflux (GOR). The aim of this study was to assess in humans the physiological effects of the supplementation of the enteral diet with different types of dietary fibre on gastro-oesophageal reflux episodes, gastric acidity and gastric emptying. METHODS: pH profiles were compared in 12 healthy volunteers between three different formula (500 kcal, 250 mL x h-1) delivered in a random order and containing either no fibre, either soy polysaccharide fibre only or mixed fibre from pea and inuline. Enteral diets were instilled through a nasogastric tube. Oesophageal and gastric pH recordings were combined with the ultrasound measurement of gastric antral area during the infusion. RESULTS: More GOR were observed with a fibre-free diet (median 4, range 1-10) than with a mixed (median 1.5, range 0-5) (P=0.04) or soy polysaccharide fibre (median 1.5, range 0-5) (P=0.04) diet. The median duration of GOR was longer with the mixed fibre (median 3.6, range 1.8-7.2) than with the fibre-free diet (mean 1.8 min, range 1-3.6) (P<0.05). The number of GOR episodes lasting more than 5 min, the duration of the longest GOR and the percent of time under pH 4 were not significantly different with the three diets. The intragastric pH profile and the ultrasound antral area were not different with all three diets. CONCLUSIONS: Addition of fibre to the enteral formula had limited effects on the onset of GOR episodes. It decreased the number of GOR but increased their duration. These effect were more pronounced with the formula containing soluble fibre. At variance, the addition of fibre had no significant effect on gastric emptying and gastric acid secretion.     

Enteral nutrition practices: similarities and differences between dietitians and physicians in Connecticut

There has been little evaluation of attitudes, beliefs, and practices of health professionals involved in the provision of enteral nutrition support. A study was undertaken to define and describe enteral feeding practices of registered dietitians (R.D.s) and physicians (M.D.s) in Connecticut. Survey questionnaires were returned by 74.5% of R.D.s and 53.3% of M.D.s. Data were analyzed for 195 respondents. Overall, there were more similarities than differences between R.D.s and M.D.s. Malnutrition was the most frequent indication for tube feedings. Dietitians and physicians selected formulas on the basis of nutrient needs of the patients, but R.D.s gave significantly more weight to formula design and nutrient composition than did M.D.s. Lactose-free low-residue, high-calorie high-nitrogen, and elemental diets were considered to be the most desirable products to include in a hospital formulary. Dietitians more frequently monitored nutrition-related parameters, whereas M.D.s followed metabolic parameters of patients on tube feeding. Physicians relied on R.D.s to recommend formulas and to provide them with enteral nutrition information. The results from this study may be useful in planning nutrition education programs, evaluating standards for enteral nutrition practice, and improving utilization of enteral nutrition therapy.     

Infection control issues of enteral feeding systems

Enteral feeding systems provide a mechanism for nutritional support for patients who may be unable to tolerate oral dietary sustenance. This review takes into account recent infection control issues relating to enteral feeding systems. The review is organized into the following areas of emphasis: infections associated with enteral tube feeding, the stability and contamination of enteral tube feeding, the risk:benefit analysis of enteral tube feeding, and the protective effects of enteral tube feeding.     

Enteral tube feeding in a cohort of chronic hemodialysis patients.

Malnutrition affects up to half of all chronic dialysis patients and is an important predictor of mortality, but the efficacy of interventions designed to improve the nutritional status of dialysis patients has been poorly studied. Specifically, although enteral tube feeding is often cited as an important option in the treatment of malnourished dialysis patients, there are few studies examining the effectiveness and complications of enteral tube feedings in adults on dialysis. We performed a retrospective analysis of a small cohort (n = 10) of chronic hemodialysis patients who received enteral tube feeding as all or part of their nutrition between January 1 and May 1, 1999, with follow-up through May 1, 2000, to assess the efficacy and complications of enteral tube feeding. Six patients received feeding via a peritoneoscopically placed (PEG) tube, 3 via nasogastric (NG) tube, and 1 patient was switched from PEG to NG feeding after an exit site infection developed at her PEG site. Seven patients received enteral feeding because of swallowing difficulties occurring after a cerebrovascular accident. Four patients were fed via enteral tube temporarily (相似文献   

Bacterial contamination of enteral feeds as a possible risk of nosocomial infection.

The degree of microbiological contamination in enteral diets was studied and the possible infectious complications that could arise in the patient after administration of an enteral feed were evaluated. Of the 208 diets studied, 56 (26.9%) were contaminated and 152 (73.1%) were sterile. Of the 56 contaminated diets, 11 could be used as delivered, but the other 45 required further modification. Of the patients who had received enteral feeding, 43 developed gastrointestinal symptoms in the first 24 h (fever, vomiting, abdominal pain and diarrhoea). Twenty-nine (67.4%) had received a contaminated diet and 14 (32.6%) an uncontaminated one. We conclude that contamination of enteral feeds may constitute a risk factor for nosocomial infection, and consider it necessary to carry out epidemiological surveillance in order to control the factors which may lead to contamination of enteral diets.     

7 g weighted versus unweighted polyurethane nasoenteral tubes--spontaneous transpyloric passage and clinical performance: a controlled randomised trial

A proportion of patients requiring enteral nutrition is at increased risk of regurgitation or pulmonary aspiration of enteral diet as a result of gastric atony or paresis. The positioning of the distal end of an enteral feeding tube beyond the pylorus into duodenum or jejunum may reduce this risk. It has been postulated that by suitable lengthening of feeding tubes and by altering the distal end tip profile or by the addition of a weight, spontaneous passage of a tube through the pylorus after pernasal insertion may be achieved. In a recent controlled trial we were unable to demonstrate any advantage to a) modifying the tip profile or b) the addition of a 2.4 g weight. This prospective controlled clinical study examined the difference between an unweighted polyurethane tube which had performed optimally in the previous study and a new 7 g weighted tube similar in all other respects. In both cases less than 50% of tubes had passed spontaneously through the pylorus when assessed at 24 h, with no significant difference in performance (p = 0.38). When comparing overall length of time that each tube remained in situ, there was similarly no significant difference between the 7 g weighted and unweighted tubes (p = 0.277). We conclude that the addition of a 7 g weight to a suitably lengthened enteral feeding tube confers no advantage on either incidence of spontaneous transpyloric passage or in prolonging tube usage. If post-pyloric feeding is indicated for a patient, positioning by either fluoroscopic or endoscopic techniques should be undertaken.     

食管癌手术细管状胃制作及术中肠内营养通路的建立

目的 介绍食管癌手术中细管状胃代食管技术及手术中经鼻或经皮穿刺方式放置空肠营养管的方法.方法 我科从2003年7月至2006年4月,对就诊的食管癌患者(接受两切口及三切口手术)采用传统管状胃代食管技术,2006年5月至2009年11月对就诊的食管癌患者采用细管状胃代食管技术,所有食管癌患者均进行术中空肠营养管置入术,术后早期给予肠内营养支持.结果 围手术期无死亡病例.改进的细管状胃代食管组患者术中管状胃长度较满意,器械吻合操作顺利,两组患者术后生存率差异无统计学意义.结论 在食管癌切除术的处理中,胃大弯侧细管状胃的使用,能提供器械吻合的便利,术中放置空肠营养管有利于术后早期肠内营养支持的开展.     

鼻空肠置管与鼻胃置管两种不同置管方式在改善重型颅脑损伤亚低温状态下早期肠内营养支持中的疗效比较

目的探讨鼻空肠置管与鼻胃置管两种不同置管方式在改善重型颅脑损伤亚低温状态下早期肠内营养支持中的作用,并比较其临床疗效。方法选择120例进行常规亚低温治疗的重型颅脑损伤患者,按简单随机抽样法分为鼻空肠置管肠内营养（鼻空肠置管组）60例及鼻胃置管肠内营养（鼻胃置管组）60例,实施鼻胃置管及鼻空肠置管后,使用肠内营养要素膳和／或肠内高营养多聚合剂实施早期肠内营养支持,两组患者在肠功能存在条件下48h内开始肠内营养,比较两组各项营养指标以及不良反应、并发症和格拉斯哥昏迷量表（GCS）评分、急性生理学与慢性健康状况11（APACHElI）评分等。结果两组患者经过早期肠内营养,营养指标均有改善,入院第14、28天,鼻空肠置管组患者的肱三头肌皮褶厚度、上臂肌围、血清白蛋白、前白蛋白、转铁蛋白、血红蛋白等指标上升幅度均明显高于鼻胃置管组,差异有统计学意义（P〈0．05）。鼻空肠置管组患者腹泻、腹胀、呕吐、胃内容物潴留及反流发生率明显低于鼻胃置管组[5．0％（3／60）比18．3％（11／60）、10．0％（6／60）比21．7％（13／60）、5．0％（3／60）比21．7％（13／60）、15．0％（9／60）比16．7％（10／60）、11．7％（7／60）比48．3％（29／60）、8．3％（5／60）比21．7％（13／60）],差异有统计学意义（尸〈O．05）。鼻空肠置管组并发症发生率低于鼻胃置管组[16．7％（10／60）比76．7％（46／60）],差异有统计学意义（P〈0．05）。鼻空肠置管组GCS评分、APACHEⅡ评分均较鼻胃置管组明显改善,差异有统计学意义（P〈0．05）。结论早期鼻空肠置管肠内营养对于重型颅脑损伤后亚低温状态下临床肠内营养实施是可行的、合理的,与鼻胃置管比较,能明显减少肠内营养的并发症,较早地达到目标营养治疗量,可以改善预后。     

Soy polysaccharide in an enteral diet: Effects on rat intestinal cell proliferation, morphology and metabolic function

The present study was conducted to compare the effect of soy polysaccharide (SP)-supplemented and fibre-free enteral diets and a normal chow diet on intestinal and colonic adaptation of rat gastrointestinal morphometrics and cytokinetics. Results showed that the fibre-free diet caused a significant decrease in various gut parameters, such as cell proliferation, tissue wet weight, and intestinal brush border enzymes, when compared to the normal gut of chow-fed rats. However the SP-supplemented enteral diet resulted in a significant improvement in several parameters in most regions along the gastrointestinal tract, when compared to orally-fed animals. These studies demonstrate that significant changes occur in the intestine as a result of enteral diets, with regional variation. Furthermore, the results demonstrate that SP stimulates crypt cell proliferation which could, in part, hasten recovery from intestinal mucosal damage. The addition of SP to enteral diets seems potentially advantageous.     

Gastrointestinal effects of modified guar gum and soy polysaccharide as part of an enteral formula diet.

Dietary fiber supplementation may improve gastrointestinal tolerance and decrease diarrhea in patients receiving enteral formula diets. To compare the effects of two dietary fibers on bowel function parameters and short-chain fatty acid excretion we fed 11 healthy men three defined enteral formula diets in random order for 18 days each. The test diets consisted of a fiber-free formula and daily intakes of maltodextrin (0 g of fiber), 15 g of total dietary fiber as an enzymatically modified guar gum, and 15 g of total dietary fiber as soy polysaccharide. Data were also collected while subjects consumed self-selected diets for 5 days. Mean transit time was longer and fecal moisture content was lower on 0 g of fiber and modified guar than on the self-selected and soy diets. Furthermore, mean transit time was slightly longer and fecal nitrogen excretion greater on modified guar compared with 0 g of fiber. Daily fecal output and frequency of defecation were greater, fecal pH was lower, and fecal butyrate concentrations were higher on the self-selected diet compared with the enteral formula diets. However, there was no difference in these parameters among the three liquid diets. Thus, despite significant differences in mean transit time, few differences in other parameters of bowel function were observed when healthy subjects consumed enteral formula diets containing 0 g of fiber and 15 g of total dietary fiber as modified guar and soy.     

Home enteral nutrition in children: an 11-year experience with 416 patients

BACKGROUND & AIMS: We report our experience of paediatric home enteral nutrition, as there is little detailed evidence published. METHODS: All patients younger than 18 years commencing treatment between January 1990 and December 2000 were included in this retrospective study. RESULTS: The study covered 416 children and adolescents, corresponding to a total of 243,844 days of home enteral nutrition (HEN). The mean (+/-SD) age of patients commencing treatment was 5.4+/-5.3 years (range 0.1-17.8). Indications were digestive disorders in 35% of patients, neurological and muscular disorders in 35%, malignancy in 11%, failure to thrive in 8%, and miscellaneous ailments in 9%. Enteral feeding comprised commercially available paediatric industrial diets in 36%, adult-type diet in 35% and infant formulas in 29%. Children received enteral feeding by nasogastric tube (53%), or gastrostomy (41%). A mechanical pump was used in 98% of the patients. The mean duration of treatment was 595+/-719 days. CONCLUSIONS: HEN can be used while treating a large group of chronic diseases of children. It can be started very early in life and is often prolonged over several years.     

Caring for Tube‐Fed Children

Enteral nutrition is the practice of delivering nutrition to the gut either orally or through a tube or other device. Many children are reliant on enteral feedings to either supplement their nutrition or as a complete source of their nutrition. Managing children on tube feedings requires a team of providers to work through such dilemmas as feeding schedules, weaning from tube feeding, sensory implications of tube feeding, treatment of pain or nausea associated with eating, oral‐motor issues, and behavioral issues in the child and family. The purpose of the current review is to summarize the multidisciplinary aspects of enteral feeding. The multidisciplinary team consists of a variable combination of an occupational therapist, speech‐language pathologist, gastroenterologist, psychologist, nurse, pharmacist, and dietitian. Children who have minimal oral feeding experience and are fed via a nasogastric or gastrostomy tube often develop oral aversions. Limited data support that children with feeding disorders are more likely to have sensory impairment and that early life pain experiences contribute to feeding refusal. There are inpatient and outpatient programs for weaning patients from tube feeding to eating. The parent‐child interaction is an important part of the assessment and treatment of the tube‐fed child. This review also points out many information gaps, including data on feeding schedules, blenderized tube feedings, the best methods for weaning children off enteral feedings, the efficacy of chronic pain medications with tube‐fed children, and, finally, the necessity of the assessment of parental stress among all parents of children who are tube fed.     

Composition of enteral diets and meals providing optimal absorption rates of nutrients in mini pigs

BACKGROUND: Commercial enteral diets differ widely in nutrient composition. It is unknown whether the nutrient composition of the diets influences intestinal absorption. OBJECTIVE: The objective of this study was to investigate the effects of different enteral diets providing 60% of energy as carbohydrate, protein, or fat or 33.3% of energy from each nutrient on intestinal absorption in mini pigs. DESIGN: Kinetics of nutrient absorption were determined by perfusing a 150-cm jejunal segment. The kinetics of absorption were used to determine optimal relations between the absorption and recovery of each nutrient. From these data, the optimal nutrient composition of the diets providing complete absorption of the macronutrients in the shortest intestinal length was evaluated. Absorption of nutrients was further determined after oral administration of 4 corresponding meals. RESULTS: With all enteral diets, the absorption of nutrients displayed saturation kinetics. Absorption rates of carbohydrate were significantly larger than those of fat and protein. Consequently, the amounts of nutrients remaining unabsorbed per unit length of jejunum differed among the macronutrients. After administration of various test meals, the length of the small intestine required for complete absorption of the nutrients depended on the composition of the meals. The shortest intestinal length for complete absorption was needed for a diet providing 48% of energy as carbohydrate, 23% as protein, and 29% as fat. This composition closely matched the nutritional requirements. CONCLUSION: The nutrient composition of diets can optimize intestinal absorption. This may be especially important in patients with malabsorption or short-bowel syndrome.     

Enteral tube feeding in the community: survey of adult patients discharged from a Dublin hospital

BACKGROUND AND AIMS: No previous study has examined the state of patients on enteral tube feeding in the community in the Republic of Ireland. METHODS: Fifty adult patients discharged from a Dublin hospital on enteral tube feeding were assessed retrospectively. RESULTS: Sixty-six per cent of the sample were over 65 years of age. Patients required enteral tube feeding as a consequence of swallowing difficulties caused by stroke (46%) or cancer of the head and neck (24%). Most patients were on full nutritional support and, in total, had spent over 49 years tube feeding in the community. Geriatric stroke patients were found to have poor functional ability and nutritional assessment proved difficult to carry out on many of these patients. Problems encountered with feeding included blocked tubes (30%), infected stoma sites (16%), and logistical problems regarding feed and equipment. Nutritional follow-up was not routine in patients with poor mobility, and 55% of patients on long-term tube feeding had not been reviewed by a dietitian in over 1 year. Patients had little faith in their general practitioner's knowledge of enteral feeding. CONCLUSIONS: While patients and families appear to cope remarkably well with tube feeding in the community, more support is necessary to ensure appropriate feeding and to monitor the nutritional status of these patients.     

Gastrointestinal disorders caused by medication and electrolyte solution osmolality during enteral nutrition

Enteral feeding tubes represent convenient avenues for medication administration and electrolyte replacement. The frequent association of medication therapy with gastrointestinal disorders during enteral nutrition prompted this evaluation of medication and electrolyte solution osmolality. It is concluded that the hypertonicity of electrolyte replacement solutions and various medications may cause gastrointestinal intolerance in patients. Electrolyte supplementation by parenteral means or by appropriate dilution and mixture with an enteral formula is preferable to bolus administration of undiluted solutions via the feeding tube. Routine admixture of medications such as antibiotic suspensions to enteral formulas cannot be recommended at this time pending specific study of drug compatibility and availability from enteral tube feeding systems.     

Nursing administration of medication via enteral tubes in adults: a systematic review

Background Enteral tubes are frequently inserted as part of medical treatment in a wide range of patient situations. Patients with an enteral tube are cared for by nurses in a variety of settings, including general and specialised acute care areas, aged care facilities and at home. Regardless of the setting, nurses have the primary responsibility for administering medication through enteral tubes. Medication administration via an enteral tube is a reasonably common nursing intervention that entails a number of skills, including preparing the medication, verifying the tube position, flushing the tube and assessing for potential complications. If medications are not given effectively through an enteral tube, harmful consequences may result leading to increased morbidity, for example, tube occlusion, diarrhoea and aspiration pneumonia. There are resultant costs for the health-care system related to possible increased length of stay and increased use of equipment. Presently what is considered to be best practice to give medications through enteral tubes is unknown. Objectives The objective of this systematic review was to determine the best available evidence on which nursing interventions are effective in minimising the complications associated with the administration of medications via enteral tubes in adults. Nursing interventions and considerations related to medication administration included form of medication, verifying tube placement before administration, methods used to give medication, methods used to flush tubes, maintenance of tube patency and specific practices to prevent possible complications related to the administration of enteral medications. Search strategy The following databases were searched for literature reported in English only: CINAHL, MEDLINE, The Cochrane Library, Current Contents/All Editions, EMBASE, Australasian Medical Index and PsychINFO. There was no date restriction applied. In addition, the reference lists of all included studies were scrutinised for other potentially relevant studies. Selection criteria Systematic reviews of randomised controlled trials (RCTs) and RCTs that compared the effectiveness of nursing interventions and considerations used in the administration of medications via enteral tubes. Other research methods, such as non-randomised controlled trials, longitudinal studies, cohort and case control studies, were also included. Exclusion criteria included studies investigating drug-nutrient interactions or the bioavailability of specific medications. Data collection and analysis Initial consideration of potential relevance to the review was carried out by the primary author (NP). Two reviewers independently assessed study eligibility for inclusion. A meta-analysis could not be undertaken, as there were no comparable RCTs identified. All data were presented in a narrative summary. Results There is very limited evidence regarding the effectiveness of nursing interventions in minimising the complications associated with enteral tube medication administration in adults. The review highlights a lack of high quality research on many important nursing issues relating to enteral medication administration. There is huge scope for further research. Some of the evidence that was identified included that nurses should consider the use of liquid form medications as there may be fewer tube occlusions than with solid forms in nasoenteral tubes and silicone percutaneous endoscopic gastronomy tubes. Nurses may need to consider the sorbitol content of some liquid medications, for example, elixirs, as diarrhoea has been attributed to the sorbitol content of the elixir, not the drug itself. In addition, the use of 30?mL of water for irrigation when administering medications or flushing small-diameter nasoenteral tubes may reduce the number of tube occlusions.     

Bacteriological safety of closed enteral nutrition delivery system.

One of the most commonly reported side effects of enteral tube feedings is diarrhea, at times attributed to the bacterial contamination of tube feedings. A closed enteral delivery system has recently been devised. It consists of a cardboard Tetrapack containing the sterile enteral nutrition formula and and independent sterile administration set; together these constitute a closed Tetrapack-administration set enteral delivery system. The bacteriological safety of this system was evaluated in vitro under controlled laboratory conditions in a series of studies. There was no or bacteriologically insignificant bacterial contamination of the enteral nutrition formula, even with repeated use of one administration set for multiple containers over 24 h. Bacteriological growth in the enteral nutrition formula was directly related to the duration of the hanging time of a Tetrapack container. No bacterial growth occurred with hanging times less than 18 h; insignificant bacterial growth occurred by 24 h. A progressive time-related increase in bacterial growth occurred between 24 and 48 h. Our data indicate that the newly developed closed Tetrapack-administration set enteral delivery system is, and will remain, bacteriologically sterile if each Tetrapack container is allowed to hang for no longer than 24 h.     

胃肠道术后早期不同途径肠内营养的应用

目的 :比较胃肠道术后早期经鼻肠管和空肠造口管二条途径进行肠内营养支持的方便性、优越性以及并发症。　方法 :选择胃肠道手术病人共 5 5例 ,按序随机分成A、B、C三组 ,A组为鼻肠管组 ,B组为空肠造口管组 ,C组为对照组。A、B二组应用肠内营养输注系统 ,在手术后 6h开始均匀输注能全力 ,分别记录术中鼻肠管和空肠造口管的放置时间、观察肠内营养支持期间的临床表现 ,并分别测定肠内营养支持前后病人的血常规、血糖、肝肾功能、电解质和营养指标以及术后并发症。　结果 :A组术中放置鼻肠管时间为 (2 9.2± 5 .6 )min ,B组术中经空肠穿刺放置Flocare可裂式空肠造口管时间为 (7.2± 2 .3)min ,二者比较差异非常显著 (P <0 .0 1)。术后肛门排气恢复时间A、B二组均比对照组快 (P <0 .0 1)。A组应用能全力后有 1例胃癌行根治术病人因腹痛、腹胀 ,不能耐受 ,中途停止使用 ;2例出现恶心、呕吐 ,经减慢输注速度后缓解 ;有 8例出现鼻咽部不适及 2例出现肺炎 ,经超声雾化、抗菌药物治疗后痊愈。B组 1例结肠癌行根治术病人因护理不当导致空肠造口管滑脱而中途停止使用 ;3例出现腹痛 ,经调整温度后缓解。所有病人没有出现腹泻、急性机械性肠梗阻、肠瘘和代谢性并发症。A组和B组应用能全力后 ,前白蛋白比对照组升高 (