Enteral feeding prevention

Greene HL, Philips BL, Franck L, et al. Persistently low blood retinol levels during and after enteral feeding of very low birth weight infants. Examination of losses into intravenous administration sets and a method of prevention by addition to a lipid emulsion. Pediatrics 1987 79 892-200. 

Enteral feedings may also prevent infection by decreasing translocation of bacteria across the gut wall. Preliminary data suggest that probiotics such as lactobacillus (along with a fiber supplement) may reduce bacterial translocation and possibly decrease pancreatic necrosis and abscess. If enteral feeding is not possible, total parenteral nutrition (TPN) should be implemented before protein and calorie depletion becomes advanced. Intravenous lipids should not be withheld unless the serum triglyceride concentration is greater than 500 mg/dL. At present, there is no clear evidence that nutritional support alters outcome in most patients with AP unless malnutrition exists. ... 

A flow diagram for the system is shown in Figure 5. Feed gas is dried, and ammonia and sulfur compounds are removed to prevent the irreversible buildup of insoluble salts in the system. Water and soHds formed by trace ammonia and sulfur compounds are removed in the solvent maintenance section (96). The pretreated carbon monoxide feed gas enters the absorber where it is selectively absorbed by a countercurrent flow of solvent to form a carbon monoxide complex with the active copper salt. The carbon monoxide-rich solution flows from the bottom of the absorber to a flash vessel where physically absorbed gas species such as hydrogen, nitrogen, and methane are removed. The solution is then sent to the stripper where the carbon monoxide is released from the complex by heating and pressure reduction to about 0.15 MPa (1.5 atm). The solvent is stripped of residual carbon monoxide, heat-exchanged with the stripper feed, and pumped to the top of the absorber to complete the cycle. 

Cyclone Separators Finer feed sohds, from 0.04 to 0.0005 m (1.5 in to 28 mesh), may be treated in dynamic separators of the Dutch State Mines cyclone type (Fig. 19-36). In cyclone separators, the medium and the feed enter the separator together tangentially at the feed inlet (1) the short cyhndiical section (2) carries the central vortex finder (3), which prevents short circuiting within the cyclone. Separation is made in the cone-shaped part of the cyclone (4) by the action of centrifugal and centripetal forces. The heavier portion of the feed leaves the cyclone at the apex opening (5), and the hghter portion leaves at the overflow top orifice (6). 

The central element of this reactor is an elongated channel in which small catalyst particles can be filled to give a mini-packed bed (Figure 3.20) [79, 80]. Gas streams enter this reaction zone as a mixture via an interleaved channel section, which also prevents the small particles penetrating the gas-feed channels. A similar type of microstmctured frit is placed at the end of the packed bed for the same function. 

Cholelithiasis can develop as a result of decreased gallbladder contractility, especially in the absence of enteral or oral intake. Lack of intestinal stimulation reduces secretion of cholecys-tokinin, a peptide hormone secreted in the duodenum that induces gallbladder contractility. The best prevention of cholelithiasis is early initiation of enteral or oral feeding, as stated earlier (to stimulate secretion of cholecystokinin, gallbladder contraction and emptying, and intestinal motility). 

The NG route is used most commonly for short-term (less than 1 month) enteral access. Some institutions prefer the OG route because of less damage to the sinuses the OG route is also useful in situations such as facial trauma, where nasopharyngeal damage prevents NG feeding. The major advantage of these routes is that the tubes can be placed quickly and inexpensively by the nurse at the bedside. 

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