Blenderized Tube Feeding in Pediatric Patients: A Systematic review

Introduction

It has been proven that children need high protein and energy intake to grow, and malnutrition in childhood can affect their health for the rest of their life [1]. Malnutrition is related to increased length of hospital stay, disease and mortality, infection, and increased hospital costs in children [2-4]. Studies have shown that the prevalence of pediatric malnutrition is about 24.1% in Germany, 18.7% in Brazil, 11% in France, 9.9% in New Zealand, 8.2% in Spain, and 31.8% in Turkey [5-11]. Enteral feeding (EF) is the preferred route of nutritional supplementation which is necessary for the management of patients who are unable to ingest food orally [12]. Although commercial formulas have been available for over 30 years, they have high osmolality and do not taste good. Several properties of commercial formulas that are rich in carbohydrates, high in saturated fat, and devoid of fiber, fruits, and vegetables are heavily involved in the pathogenesis of the cardiovascular disease and pulmonary diseases. The preservatives in these formulas may also be associated with inflammatory diseases [13-15]. Children with swallowing problems, neurological disorders, and etc. often need enteral nutrition using primarily commercial formulas; however, BTFs have become more popular for pediatrics and have come out as part of home enteral feeding in recent years [16-19] because BTFs are more natural, healthier, and better tolerated than the commercial formula [19, 20]. Studies also have shown a positive clinical outcome for using BTFs in children [13, 21]. A study conducted in 2015 reported that 57% of nutritionists use and recommend BTFs for pediatric populations [18]. Concerns about contamination, infection, and nutrient content of BTFs should be thoroughly trained by a nutritionist to minimize their hazards [22]. Advantages of BTFs include using organic foods or genetically modified organism free foods, preventing food allergies, reducing feeding intolerance, such as reduced gagging and retching, improving intestinal function, increasing dietary diversity, as well as reducing oral aversion, chronic diarrhea, and costs [14, 20, 21, 23, 24]. In particular, BTFs allow children's families to tailor a diet to their pediatric needs [14]. Given that, the use of BTFs in children has increased in recent years and no review study has been conducted in this regard. Therefore, this study aimed to investigate the effect of blenderized tube feeding in pediatric patients.

Materials and Method

Information sources

The articles conducted on the blenderized tube feeding in pediatric patients were reviewed from 2010 to 2020, to find the recent investigations. Four databases were used: Scopus, PubMed, Science Direct, and Google Scholar. The references of included articles were also checked for related studies. The search strategy used for the systematic search was: ("blenderized tube feeding" OR "blended formula" OR "homemade enteral nutrition") AND (" pediatric" OR "Children").

Selection criteria and quality assessment

Two reviewers independently screened the databases and reviewed the titles, abstracts, and full texts to determine the articles which met the inclusion criteria and any discrepancies were resolved by consensus.

Studies which investigated the effect of blenderized tube feeding formulation in pediatric patients and provided data on their calories and macronutrients were included. The exclusion criteria included failure to report the used formulation, and failure to report calories, fat, protein, and carbohydrates content of BTFs.

Data extraction

The details extracted for each of the studies included the first author’s last name, the time of conducting the study, publication date, and blenderized tube feeding in pediatric patients.

Results

Figure 1 depicts the selection process of the studies within the PRISMA diagram. In the systematic literature search, 103 articles were obtained from Scopus, PubMed, Science Direct, Google Scholar as well as the relevant studies identified in cross-references. After the elimination of duplicates, 79 articles were considered eligible for title/abstract screening, 24 of which were retrieved for full-text assessment. Finally, 6 eligible studies were selected for the systematic review. The results showed that the calories of BTFs were about 1 1kcal/g, protein 13%-22%, fat 30%-34%, and carbohydrates 45%-55% (Table 1).  The carbohydrates in BTF are easily obtained from fruits, starchy vegetables, whole grains, and carbohydrate-based calorie additives. Protein is also provided through cow milk or milk powder and meat. Vegetable oil, olive oil, and etc. have also been used to satisfy fat intake. The blenderized tube feedings also contained fiber and phytochemicals. Phytochemicals are an extensive category of plant compounds that have been shown to have significant health benefits from fruits, vegetables, beans, cereals, and plant-based beverages.

Figure 1. Flow diagram showing the results of the searches

Table 1. Blenderized tube feeding in pediatric patients

 Discussion

The most common diseases in children that require enteral feeding include congenital abnormalities (42%), perinatal problems (38%), and neurologic diseases (16%)[28]. Tables 2 reveal the criteria for selecting the appropriate patients for BTF [29]. Although children also use commercial formulas, due to the benefits of BTFs, health professionals and patients' families have become more interested in using BTFs. However, studies have shown that the risk of microbial contamination can lead to insufficient energy and nutrient content. This is due the fact that BTFs prepared in hospitals do not have a specific formula and are prepared by mixing different foods, such as milk, meat, juice, vegetables, etc. in completely different amounts. Therefore, the amount of energy, carbohydrates, proteins, and fats of these solutions are different [30-32]. After the preparation of BTFs, they should be stored within the temperature range of 2-8°C. Personnel should wash, dry, and disinfect hands frequently and use masks before preparing BTFs for non-sterile, blended, diluted, or decanted foods. Notably, the administration time should not exceed four hours [29, 33]. During the handling process, foods should not be exposed to temperatures  of 10-60°C for more than 30 minutes, and the storage time should be less than 12 hours [34].  Parents and hospitals could follow the guidelines provided by
American Academy of Nutrition and Dietetics (www.homefoodsafety.org) and United States governmental agencies (www.foodsafety.gov), which have been published to minimize microbial contamination. The optimal and safest approach
to minimize microbial contamination is the implementation of a hazard analysis critical control points (HACCP) system. The wide variety of microorganisms that have been detected so far may be due to inappropriate manufacturing practices and storage conditions. Efficient manufacturing practices and the contentious control of processing lines
could reduce the rate of contamination, especially in the case pathogenic species. In addition, the strict implementation of microbial recipes (e.g., HACCP), good manufacturing practices, and good hygiene practices (GHPs) proposed by the World Health Organization (WHO) and Food and Drug Administration (FDA) could reduce the microbiological contamination of enteral nutrition [35].

 Designing the diet

Energy

Energy needs vary considerably between people depending on the patient's age, activity, and health status, but infants and children require more energy than adults (Table 3) [36]. As a starting point in nutrition, nutritionists may want to consider consuming 10% more energy than the amount a child currently consumes [37]. Tools for the starting point to create a diet plan based on calorie goals are presented in Table 4. Examples of food sources for BTFs can be found in Table 5.   Nutrients can be categorized into carbohydrates, proteins, and fats that provide calories, and vitamins, and minerals. The energy in foodstuffs is released via the oxidation of carbohydrates, fats, and proteins in the body, and the chemical energy needed to maintain metabolism and other body functions is produced [38].  Lack of macronutrients can be categorized
as marasmus (primary calorie deficiency), kwashiorkor (primary protein deficiency), and marasmic kwashiorkor (calorie and protein deficiencies). Calorie deficiency is a primary nutrient deficit among these children [39]. The amount of energy provided by macronutrients is as follows: carbohydrate: 4 kcal/g, fat: 9 kcal/g, and protein: 4 kcal/g [38]. The acceptable range of macronutrients for children and adolescents is as follows: carbohydrates: 45% -65% of total calories, protein: 5%- 20% of energy intake for ages 1 to 3 and 10%-30% for ages 4 and older, fats: 30%-40% of energy intake for ages 1 to 3 and 25%-35% for ages 4 and older [39]. The practice of BTFs should be controlled by nutritionists [20]. 

Table 3. Average energy requirements for the different age groups

Table 4. Tools for the starting point to create a diet plan based on calorie goals

Table 5. Examples of food sources for BTFs

Protein

The first step is to select the right source of protein; since plant proteins are not used as much as animal proteins [29]. Animal-derived proteins have a higher protein efficiency ratio (PER), biological value (BV), net protein utilization (NPU), and protein digestibility-corrected amino acid score than vegetable protein [40, 41]. Some children are allergic to foods, such as cow milk, egg, peanut, soybean products, finfish, shellfish, corn, and wheat [42]; therefore, these foodstuffs should be from their diets, and when they are removed, the allergic child might deficient in vitamin D, calcium, phosphorus, and B vitamins. Allergic children should seek the advice of a nutritionist to provide these nutrients through alternative sources [22]. At least consumption of 1.5 g/kg/d of protein and 58 kcal/kg/d can equilibrate nitrogen and energy balances in children up to 4 years [43]. The American Society for Enteral and Parenteral Nutrition (ASPEN) suggested that the protein required for pediatric is 2 to 3 g/kg/day for children less than 2 years, 1.5 to 2 g/kg/day for those aged 2 to 13 years, and 1.5 g/kg/day for those aged 13 to 18 years [44]. Foods, such as milk and formula can be used as part of liquid protein. It is not recommended to use more than 4 to 8 ounces of liquid protein; since a thicker viscosity is more useful for retching and gagging. Then meat or yogurt can be used for the rest of the required protein. Of course, all the required protein can be obtained from meat and yogurt without liquid protein (milk), but the problem is the pressure through the syringe during feeding [27].

Fat

Reducing fat intake in growing children which reduces the supply of omega-6 and omega-3 essential fatty acids, has unfavorable effects on growth and leads to unfavorable lipoprotein profiles, and increases the consumption of potentially harmful trans fatty acids [45]. The purpose of added fat is to provide calories and essential fatty acids. If linoleic acid provides at least 1% of the total calories, the deficiency of essential fatty acids can be prevented, but the recommended limit is 3-4% of the total calories [46]. In a 1500 kcal diet, the least amount of linoleic acid needed is recommended to be between 1.7 and 6.7 g/d [47]. Essential fatty acids can be obtained from safflower, sunflower, soy, and corn oils, but since these fatty acids are the main sources of Omega-6 fatty acids, their additional administeraton is harmful due to pro-inflammatory and immunosuppressive effects [48, 49].  Canola and olive oil are commonly used as fat sources because they have low saturated fat content (1 to 2 tablespoons) [27]. Medium-chain triglycerides can be used to provide fat due to their unique attributes (better water miscibility, faster hydrolysis, better absorption into intestinal mucosal cells, and transfer of medium-chain fatty acids into portal circulation than long-chain triglycerides) [50]. Total lipid consumption should be 3-4 g.kg^-1. day^-1 [51].

Carbohydrates

Carbohydrates are usually tolerated except for lactose and they do not have any gastrointestinal side effects. Glucose is a fast source of energy and the only carbohydrate available in the circulation [46] . Carbohydrate sources can be obtained from fruits and vegetables. Squash, carrots, sweet potatoes, peaches, apricots are good sources of vitamin A, beta-carotene, carbohydrates, and calories. Prunes or bananas are also high in potassium and calories. Applesauce, pears, green peas, green beans, spinach sauces are also good sources of vitamin C. Cereals are also used to increase calories, carbohydrates, and fiber and as a thickener [27]. In BTFs use slowly digestible carbohydrates from legumes and whole grains, which decreases the hazard of airway inflammation compared to commercial diets [52, 53]. Low dextrose equivalent (DE) maltodextrins have longer chains of glucose molecules, are sweeter and more soluble than those with high DE and can be used in intestinal nutrition, while high DE maltodextrins increase osmolarity and diarrhea [46]. European Society for Clinical Nutrition and Metabolism(ESPEN) is recommends 15–30 g/d fiber in the diet of patients who use enteral nutrition [54].

Micronutrients

Specific micronutrient deficiencies that may occur more frequently are iron, zinc, calcium, vitamin D, and B vitamins deficiency. The sources of these micronutrients are summarized in Table 6 [39]. Vitamins and minerals are found in the market in liquid and solid form to be added to BTFs.  Given sodium is often low in BTFs, in the first option, salt can be used to supply sodium, but if salt is not suitable, Pedialyte, juice (original), chicken broth, pacific foods vegetable broth, Knorr chicken bouillon can be used [22]. Cutting, post-harvest water loss (especially in leafy vegetables), and cooking cause loss of nutrients. The use of microwaves causes less nutrient loss than heating methods (except steam), and minimizing the amount of water consumed seems to further decrease these losses [55].