Commencement Of Parenteral Nutrition Research Articles

Assessing Appropriateness of Parenteral Nutrition Usage in an Acute Hospital

Although parenteral nutrition (PN) has become an integral component of patient care, the risks and costs associated with this therapy must be weighed against the benefits. The Department of Nutrition and Dietetics at our tertiary referral, university-affiliated hospital has audited the use of enteral nutrition and PN based on criteria devised from guidelines developed by the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.). We aimed to examine the use of PN over time and in particular to investigate the appropriate and inappropriate use of this feeding method. Each patient referred for PN was assessed by a dietitian and need for PN evaluated. The appropriateness of the PN was categorized according to predefined criteria. A total of 1191 patients had 1409 episodes of PN during the study period. According to the predefined criteria, 82% of PN episodes were considered "appropriate." PN was "appropriate but avoidable" in 13% of cases. In 5% of episodes, the commencement of PN was considered "inappropriate." The use of appropriate PN increased significantly over the study period (P = .018). Most PN episodes were deemed appropriate. We saw 5% inappropriate usage, which is lower than reported in comparable studies. This study underlines the importance of continuous audit and evaluation of practice to maintain appropriate and evidence-based practice in nutrition support.

Clinical Validation of ELISA Assays for Insulin-Like Growth Factor-II (IGF-II)

Background : Insulin-like growth factor-II (IGF-II) is known to be dysregulated in malnutrition and in non-islet cell tumour hypoglycaemia (NICTH). Its measurement may be used diagnostically in the latter condition but little information is available on its utility as a nutritional marker. The aims of this study were to clinically validate two ELISAs for measurement of IGF-II in these conditions and to provide further information relevant to their use in nutritional contexts. Methods : IGF-II concentrations were measured by extraction and non-extraction ELISA and RIA in 20 malnourished patients referred for nutrition support. IGF-II concentrations were also measured by both ELISAs in 10 subjects with clinical features of NICTH. Results : Baseline IGF-II measured by both ELISAs correlated with body weight in patients referred for parenteral nutrition (PN) (P < 0.05). Following commencement of PN, IGF-II concentrations climbed from baseline reaching statistical significance at days 5 and 7 of PN (P < 0.05). In specimens from subjects considered to have NICTH, IGF-II results from both ELISAs were positively biased compared to those measured by RIA. In comparison to RIA, the non-extraction ELISA yielded two false positive results and the extraction ELISA one false positive and one false negative result. Conclusions : IGF-II may have a place in monitoring of nutrition support and merits further study of its utility as a nutritional marker. Whilst the ELISAs investigated can sensitively detect IGF-II and are valid for the measurement of IGF-II in nutritional contexts they are unlikely to replace RIA for the purpose of investigating NICTH. J Endocrinol Metab. 2012;2(2):72-81 doi: https://doi.org/10.4021/jem82w

Timing of the initiation of parenteral nutrition in critically ill adults

BackgroundCritical illness in hospitalized patients induces anorexia: aninability to eat suitably, predisposing to nutritional deficit,weakness, infections, increased duration of mechanicalventilation, delayed recovery and death [1]. To date,whether artificial nutritional support improves outcomesfor critically ill patients is unclear. Enteral nutrition isassociated with fewer complications than parenteral nutri-tion, and is less expensive [2], but enteral nutrition alonedoes not often achieve caloric targets. Combining paren-teral and enteral nutrition could prevent nutritional deficit.However, this strategy may carry the risk of overfeeding,which has been associated with complications such as liverdysfunction [3]. Current clinical practice guidelines fornutritional support in critically ill patients are largely basedon expert opinion, and differ substantially across conti-nents, in particular about the timing to start parenteralnutrition. The European Society of Parenteral and EnteralNutrition (ESPEN) recommends the commencement ofparenteral nutrition within 2 days after admission to theintensive care unit (ICU) for patients who cannot be ade-quately fed enterally [4], while the American and Canadianguidelines recommend early initiation of enteral nutrition,but suggest starting parenteral nutrition after a week inpatients who are not malnourished at baseline [5].SummaryCasaer and coworkers [6] in a randomized, multicenter trial,comparedanearlytoalateinitiationofparenteralnutritioninadults admitted to the ICU who were not malnourished atbaseline [body-mass index (BMI) of C17] in order to sup-plement insufficient enteral nutrition. The primary endpoints were the number of days spent in ICU (for survivorsand non-survivors), and the time to discharge from the ICU.In 2,312 patients, parenteral nutrition was initiated within48 h after ICU admission, whereas in 2,328 patients, it wasnot initiated before the eighth day from admission. ThemedianstayintheICUwas1 dayshorterinthelate-initiationgroup than in the early-initiation group (3 vs. 4 days,respectively, P = 0.02), which was reflected in a relativeincrease of 6.3% of the likelihood of earlier discharge alivefrom the ICU [hazard ratio 1.06, 95% confidence interval(CI), 1.00–1.13, P = 0.04]. Considering the secondary out-comes, patients in the late-initiation group had fewer healthassistance related infections (22.8 vs. 26.2%, P = 0.008), alowerincidenceofcholestasis(32.6vs.38.4%,P\0.001),areduction in the proportion of patients requiring more than2 days of mechanical ventilation (36.3 vs. 40.2%,P = 0.006), a median reduction of 3 days in the duration ofrenal replacement therapy (7 vs. 10 days, P = 0.008) and areduction in mean health care costs of €1,110 as comparedwith the early-initiation group (€16863 vs. €17973,P = 0.04). The safety outcomes (in-hospital mortality rates,survival at 90 days, rates of nutrition-related complications)weresimilarinthetwogroups,buthypoglycaemiawasmorecommon in the late-initiation group patients (3.5 vs. 1.9%,P = 0.001). Although enteral nutrition was initiated if pos-sible in the majority of patients, the post hoc subgroupanalyses including patients for whom early enteral nutritionwas contraindicated showed the same results.

A single enteral feed prior to the commencement of parenteral nutrition ameliorates the incidence of steatosis in parenterally fed neonatal piglets

Total parenteral nutrition (TPN) in neonates is associated with liver dysfunction. The initial post-partum enteral feed plays a key role in establishing post-partum metabolic regulation. Therefore absence of enteral nutrition, in neonates commencing TPN immediately post-partum, may induce metabolic abnormalities driving liver dysfunction associated with TPN. To study the effect of a single enteral feed prior to commencing TPN on the aetiology of liver dysfunction in neonatal piglets maintained on TPN for 7 days. Piglets were delivered by caesarean section on day 112 of gestation. They were divided into two groups, receiving either no enteral intake (N) or a single 10 ml feed of sows milk (EF) before being fed by TPN for 7 days, after which tissue samples were taken. Hepatic lipid metabolism and enzyme activity were assessed coupled with metabolomic profiles. Piglets receiving no enteral nutrition accumulated more hepatic lipid (N 7.58 ± 0.84, EF 5.21 ± 0.30 g lipid·100 g of liver−1, P = 0.013). Hepatic PEPCK activity was increased in EF piglets (N 8.59 ± 0.95, EF 10.57 ± 1.38 U·mg protein−1, P = 0.024), alongside reduced hepatic lactate and key amino acid concentrations and increased muscle glucose. A single enteral feed immediately after birth alters hepatic metabolism, possibly by switching from lipid biosynthesis to gluconeogenesis, thereby reducing hepatic steatosis that occurs in response to TPN.

The induction of a specific protease for insulin-like growth factor binding protein-3 in the circulation during severe illness

The insulin-like growth factors (IGF-I and IGF-II) are almost completely bound in the circulation to specific binding proteins (IGFBPs). These IGFBPs appear to play a pivotal role in maintaining circulating levels and modulating the delivery of the IGFs to the tissues. A large proportion of the circulating IGFs are bound with high affinity to one of the binding proteins. IGFBP-3. The mechanism by which these IGFs are transferred from the circulatory pool to the tissue receptors is at present unclear. Recent studies in late pregnancy have demonstrated the presence of specific proteases which may modify the IGFBPs such that their affinities for the IGFs are reduced. In this paper, we have demonstrated the presence of a heat-sensitive cation-dependent proteolytic enzyme specific for IGFBP-3 in the serum of five severely ill patients. The activity of this protease was found to vary in these patients, becoming more apparent during fasting than when studied after commencement of parenteral nutrition, indicating that one of the influencing factors in the activity of this protease is the nutritional intake of the patient. Age- and sex-matched healthy adults were also studied in a similar protocol, but no proteolytic modification of any of the IGFBPs was found in any of the samples examined. As the levels of both IGF-I and IGF-II were found to be low in the patients, the presence of a circulatory protease suggests that this may be an adaptive response to increase the bioavailability of the IGFs and possibly to improve the nitrogen retention and counter the catabolic state in severe illness.

Variant acute intermittent porphyria in a child

A child who was grossly malnourished and who showed increased excretion of porphyrin and porphyrin precursor had normal activity of erythrocyte porphobilinogen deaminase (EC 4.3.1.8) and leukocyte protoporphyrinogen oxidase (EC 1.3.3.4). Clinical symptoms, coincident with the excretion of rose-colored urine, were consistent with the diagnosis of an acute porphyria. The disease resolved spontaneously after the withdrawal of carbamazepine and sodium valproate and the commencement of parenteral nutrition with subsequent carbohydrate loading. In addition to normal concentrations of enzyme activities, the patient is unusual in presenting before puberty and in having no family history of porphyria.

Effect of parenteral nutrition on body composition in the critically ill patient

The efficacy of intravenous hyperalimentation in the critically ill patient was evaluated by body composition measurements performed with a multiple isotope dilution technic. The size of the body cell mass was evaluated by measuring the total exchangeable potassium and the intracellular water volume. The total exchangeable sodium and the extracellular water volume were both measured to evaluate the extracellular supporting component of body composition. These measurements were performed in two groups of severely ill patients who were in a chronic catabolic state. The first group of sixteen patients received intravenous hyperalimentation and the second group of eighteen patients served as controls in that they were not hyperalimented. Similar measurements were performed in sixteen normal volunteers to define the normal range for the various body composition parameters. In the nonalimented patients, there was a significant decrease in the body cell mass accompanied by an expansion of the extracellular supporting component of body composition. Similar changes occurred in the patients receiving intravenous hyperalimentation. However, the magnitude of these changes was not as great. Thus, intravenous hyperalimentation tended to preserve the body cell mass and prevent expansion of the extracellular component of body composition. To determine if the body composition abnormality in the hyperalimented patients was due to continued catabolism, measurements were performed twice a mean of 25.1 ± 4.6 days apart in twelve patients receiving parenteral nutrition. Body composition in these patients remained unchanged, indicating that the body composition abnormality observed in the hyperalimented patients had occurred before the commencement of parenteral nutrition and was not corrected by it.