Parenteral nutrition case study

Hematological abnormalities have been found to be associated with prolonged administration of intravenous fat emulsion in children on a program of long-term cyclic parenteral nutrition. Recurrent thrombocytopenia is common and platelet lifespan is reduced. In one study (80), thrombocytopenia occurred in 66% of patients, but most of these had taken drugs that might have interfered with platelet function. Hypercoagulability was not found in the majority of cases. 

Preparations for total parenteral nutrition (TPN) are complex formulations intended for administration by the intravenous route. TPN preparations are formulated as aqueous solutions or hydrophilic (oil-in-water) emulsions they may contain amino acids, carbohydrates, fatty acids, emulsifiers, electrolytes, trace metals, vitamins, and minerals (Hutchinson, 1998 Trissel, 2001). In certain cases, drugs are added to the preparations prior to administration. The environment is thus rather heterogeneous, and the photochemical stability of different components can vary from formulation to formulation and be hard to predict. It is necessary to perform experiments based on studies of the actual composition to obtain correct information concerning photostability of the formulation or components present. 

Cr(III) in humans comes from several independent cases of patients on total parenteral nutrition (TPN), when the absence of Cr(III) in TPN solutions led to severe symptoms of glucose intolerance that were reversed by Cr(III) supplementation (461, 473). However, the elevated glucose levels in most of the studied TPN patients were unaffected by Cr(III) supplementation (5, 474). Most studies failed to detect any significant Cr(III) related metabolic changes in healthy humans on normal diets [(4, 6) and references cited therein]. 

Natural diets will usually contain sufficient variety that such a low level of n-3 fat intake would be avoided. However, when the diet is limited to one food source such as when formulas are given to infants or in the case of parenteral nutrition, very low n-3 fatty acid intake becomes possible. In related studies in which nine groups of rats with varying levels of brain DHA were assessed for spatial task performance, it was observed that significant changes in performance could not be observed when the DHA level was more than 60% of the n-3 Adq level (47). Thus, the loss of 20% of brain DHA described in the human autopsy studies would probably not be expected to lead to spatial task performance losses. However, in many in-... 

Systematic reviews In a systematic review of all articles in which the use of parenteral fish oil to manage cholestasis during parenteral nutrition was reported, six case reports (10 patients) and two cohort studies (12 and 18 patients) were analysed [3 ]. Fish oil-derived emulsions reversed pre-existing cholestasis. 

The indications for the use of vena cava catheters are measurement of central venous pressure, infusions and transfusions in critical circulatory conditions, long term infusions, parenteral nutrition and administration of hypertonic solutions. While the use of caval catheters may save many lives, it is not without risks. In a one year prospective study performed in nine hospitals in Germany, Austria and Switzerland- we evaluated our experience with 3241 central venous catheterizations and compared the results with other reported series (11,000 cases). 

Observational studies The effect of peripherally inserted and non-peripherally inserted catheters on infection rates in adults requiring home parenteral nutrition (PN) has been examined in a retrospective study of 101 patients. Seventy-five percent of infections developed within the first 6 months of hospital discharge, and most of these were attributed to gram positive organisms. Patients with peripherally inserted catheters had a significantly higher rates of infections compared with non-peripherally inserted catheters (P=0.018) [lOl ]. A four-year review of 145 cases of peripherally inserted central catheters for long-term PN in infants with intestinal failure showed that the overall... 

In a prospective study of enteral-based nutritional support regimen in bums and tramna patients, those receiving the highest amoxmts of enteral calories within the first week had the highest incidence of ventilator-assisted pneumonia and the lowest incidence of bacteraemia. PN was associated with a significantly increased risk of bacteraemia (OR=2.5 95% Cl 1.8-3.5), ventilator-assisted pneumonia (OR=2.5 95% Cl 1.7-3.3), and death (OR=1.9 95% Cl 1.1-3.1) [104 ]. A retrospective review of 12 cases of multiple sclerosis patients on home PN showed that there was no improvement in their fxmctional status there were also no significant changes in liver enzymes and bilirubin [105 ]. Five of the patients died within two years form causes unrelated to parenteral nutrition. 

Clinical signs and symptoms of hypoglycemia are reported occasionally most cases are subclinical, but severe cases have been described (SEDA-13, 815). A study of the effect of quinidine on glucose homeostasis in Thai patients with malaria showed a near doubling of plasma insulin concentrations and a corresponding fall in serum glucose concentrations. An additional factor may have been impaired nutritional status and the effects of parenteral quinine in severely ill patients not taking food (SEDA-13, 815 SEDA-14, 240 SEDA-18, 288). 

A number of early case reports described warfarin resistance in patients taking enteral feeds that contained high levels of added vitamin Kx- These products were then reformulated to contain lower amounts of vitamin Kx, commonly now about 4 to 10 micrograms per 100 mL however, some cases of interactions have still been reported, and one study in children reported that those receiving enteral nutrition (mostly vitamin K enriched formula) required 2.4-fold higher maintenance warfarin doses. Lipid emulsions containing soya oil might contain sufBcient natural vitamin Kx to alter warfarin requirements. Parenteral multivitamin preparations may also contain vitamin Kx. 

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