Inadequate oral intake in surgical patients: a rational indication for nutritional support

Seven days or more of inadequate oral intake (IOI) inevitably results in a deterioration in nutritional status. Despite this well-known fact, little information is available as to the frequency with which such periods of IOI occur in clinical practice. This study results from an audit of IOI in a gastroenterological unit over a 6-month period. The results demonstrate that 17% of patients sustained significant periods of IOI of 7 days or longer. This has important implications with regard to the provision of adjuvant nutritional support.     

Diet and disadvantage: observations on infant feeding from an inner city

Background: There are few detailed nutritional studies analysing dietary intakes and weaning practices of inner city infants aged 0–12 months. Pasteurized cow's milk (PCM) is not recommended as a main drink until after 1 year of age, although early usage is still common. Premature introduction of pasteurized cow's milk is associated with increased risk of iron deficiency anaemia. Methods: We therefore prospectively examined the dietary effect of early introduction of pasteurized cow's milk on the nutritional intake of 100 infants (mean age at recruitment 7.8 months), whose mothers had already elected to introduce cow's milk before the recommended age of 12 months in a deprived inner city area. In addition, a retrospective questionnaire on feeding practices and food choices was administered and information on parental education and employment was collected, together with a 3-day dietary diary of weighed intakes at recruitment. Results: The results indicate that weaning practices are handed down from family and friends and are intuitive rather than informed. Over 80% of the infants had intakes of iron, zinc and vitamin D below the reference nutrient intake (RNI) and a further 41% had low vitamin C intakes. Prior to introduction of PCM, there was also misuse of infant formula. Twenty per cent added an extra scoop of powder to the feeds, 10% added milk powder to the bottle before addition of water and 30% used microwave ovens to heat the infant bottle. Conclusion: Feeding practices in a deprived inner city area differed substantially from guidelines and infants were at risk of developing nutrient deficiencies as well as poor feeding practices.     

Cardiovascular malformations, work attendance, and occupational exposures during pregnancy in Finland

To explore for associations between occupational factors and cardiovascular malformations, information on the parents of 160 infants with cardiovascular malformations and 160 control parents was studied. The case infants had been reported consecutively to the Finnish Register of Congenital Malformations. All mothers were interviewed identically after delivery, using both open and pro forma questions about detailed work tasks, exposures, and leisure activities during pregnancy. The interview information was evaluated blindly. Neither parental occupational titles nor maternal working per se gave new clues to the teratogenic risk; nor did shift working, wearing of personal protective equipment, or the mother's own opinion on exposures during pregnancy. Identified occupational exposures, as categorized by an industrial hygienist, showed no remarkable associations to cardiovascular malformations. Few mothers were exposed substantially to specific occupational hazards. Comparing mothers who used medications in the first trimester with those who did not showed an odds ratio of 2.2 (95% confidence interval 1.3-3.9) when adjusted for potential confounding by multivariate logistic methods.     

Nutritional considerations in intravenous drug misusers: a review of the literature and current issues for dietitians

Poor nutritional status and inadequate dietary intake in intravenous drug misusers (IVDMs) is a well-recognized problem among those involved in their care. However, there are very few published studies to substantiate these observations. This paper provides a review of the current literature and outlines the aims of dietary advice for IVDMs.     

Expression of Fos in rat brain in relation to sodium appetite: furosemide and cerebroventricular renin

Two experiments were performed to investigate the relationship between the expression of sodium appetite and the appearance of Fos-like immunoreactivity (Fos-IR) in the brain of rats. In the first experiment, rats were depleted of sodium by treatment with furosemide 24 h prior to sacrifice and without access to either food or sodium solution. Some rats had access to distilled water, and others had no fluids available during the 24 h. All of the furosemide-treated rats showed Fos-IR in both the subfornical organ (SFO) and around the organum vasculosum laminae terminalis (OVLT). Rats with access to distilled water during the depletion period showed no Fos-IR in the supraoptic (SON) or paraventricular hypothalamic nuclei (PVN) and, in parallel behavioral studies, comparably-treated rats consumed only 0.3 M NaCl solution at the end of the 24 h. In rats that had no fluids during the deprivation period, only about one half showed Fos-IR in SON and PVN and, in parallel behavioral studies, comparably treated rats consumed both water and 0.3 M NaCI solution at the end of 24 h. In a second experiment, cerebroventricular administration of renin stimulated short latency intake of 0.3 M NaCI and water. The relative intakes of water and NaCl were comparable at a low dose of renin, but intake of water exceeded that of NaCl after higher doses. Renin induced Fos-IR in SFO, MnPO, peri-OVLT region, SON and PVN. Both Fos-IR and fluid intake were antagonized by administration of losartan, an angiotensin 11 type 1 receptor antagonist. Thus, only the circumventricular organs of the lamina terminalis showed Fos-IR during each natriorexigenic regimen in these studies. These data support the view that Ang 11 of both central and peripheral origin activates the SFO and/or peri-OVLT region and contributes to sodium appetite.     

Kupffer cell activation in the survival discrepancy between liver grafts from enterally and parenterally fed donors

Abstract This study was designed to investigate the effects of differences in the route of nutritional support of the donor on cold ischemia/reperfusion injury. Participation of Kupffer cells in these effects, based on the analysis of hepatic energy metabolism in early phases of reperfusion was also investigated. Orthotopic liver transplantation was performed between Large-White pigs weighing 20–30 kg after a 4-h cold preservation of the graft in Euro-Collins solution at 4°C. One group was fed orally with a standard laboratory diet (FED group, n = 5), a second group was fasted and given 20% glucose intravenously (12 kJ/kg per day) (PEF group, n = 5), and a third group was fed orally with a standard laboratory diet and given GdCI₃ (10 mg/kg) intravenously 24 h before operation (FEDGD group, n = 5). These treatments were given for 7 days prior to harvesting. The survival time was significantly longer in the PEF (34.8 ± 5.5 days) and FEDGD (28.0 ± 11.9 days) groups than in the FED (9.8 ± 2.0 days) group ( P < 0.05). The serum hyaluronic acid elimination rate determined from 1 to 2 h after reperfusion was significantly lower in the FED group than in the other two groups ( P < 0.001). The glycogen content of the livers 1 h after reperfusion in all three groups had been consumed rapidly, but the ATP content of the livers was significantly reduced in the FED group alone ( P < 0.01). Hepatic FFA clearance (C_FFA) was moderately increased in all three groups in the early phase after reperfusion, but it was higher in the FED group than in the other two groups, with significant differences 1 and 2 h after reperfusion ( P < 0.05). In conclusion, parenteral nutrition of the donors reduced cold ischemia/reperfusion injury which is related to Kupffer cell activation and, thus, was better than enteral nutrition for donor management.     

Functional compartmentalization of energy production in neural tissue

Previous work in our laboratory has shown that neural trauma results in a disparity between oxidative and glycolytic rates. In non-neural tissue, glycolysis and oxidative phosphorylation have been shown to work independently of one another, a phenomenon known as "energy compartmentalization". We believe that functional compartmentalization of energy production may also occur in the brain with glycolysis providing energy for membrane bound ionic pumps. Spreading depression, induced in rodent brain by topical KCl application, results in K+ shifts. The restoration of K+ gradients is accomplished by energy dependent Na(+)-K+ pumps. If these pumps depend upon glycolysis, blocking glycolysis should prevent reconstitution of normal [K+]e levels. The present series of experiments were designed to suggest that energy compartmentalization may also exist in brain, and that glycolytic energy production is preferentially used by Na(+)-K+ pumps to maintain normal ionic homeostasis by observing the dynamics of spreading depression induced K+ shifts before and after glycolytic blockade. Spreading depression was associated with increased K+ (48.6 +/- 16.6 mM over control) that normalized within 2.9 +/- 0.3 minutes. Following superfusion with a glycolytic blocking agent, spreading depression produced similar increases in [K+]e (40.6 +/- 12.0 mM over control) but time for reconstitution of the normal [K+]e was 400% longer than controls (2.9 +/- 0.3 to 14.9 +/- 2.1 minutes, P less than 0.001). Time required for recovery of EEG was identical pre- and post-blockade. We believe these data suggest that energy compartmentalization may exist in neural tissue and that glycolytic pathways of energy production are functionally tied to membrane Na(+)-K+ pumps.(ABSTRACT TRUNCATED AT 250 WORDS)     

Role of dietary fat in calorie intake and weight gain

This paper reviews the literature on the role of dietary fat in calorie intake and body weight gain in humans and laboratory animals. An overview of 40 animal studies which compared growth on high-fat (HF) and high-carbohydrate (HC) solid/powdered diets indicated that the HF diet elicited greater weight gain in 33 out of 40 studies. Enhanced growth on the HF diet was often, but not exclusively, attributable to greater caloric intake. Additional evidence for the growth-enhancing effect of HF diets emerges from "diet option" and "supermarket" feeding studies in rats, and experimental and epidemiological studies in humans. Three principal factors that contribute to the different responses to HF and HC diets are (a) caloric density, (b) sensory properties and palatability, and (c) postabsorptive processing. It is concluded that both calorie intake and metabolic energy expenditure are biased towards weight gain when a HF diet is consumed, and that the high caloric density of high-fat diets plays a primary role in weight gain. Humans may be biologically predisposed to gain weight when a HF diet is consumed.     

The reduction of water intake in rats caused by a low dose of apomorphine is unaltered by α-methyl-p-tyrosine: are autoreceptors not involved?

Summary Low doses of the dopamine (DA) agonist apomorphine (APO) induces a behavioural syndrome characterized by reduced spontaneous activity, reduced food and water intake and induction of yawning and penile erections. Traditionally these effects of APO have been considered to be caused by a preferential stimulation of DA autoreceptors, causing a decreased amount of transmitter at the postsynaptic receptors. If this is so, it could be hypothesized that 1) the same behavioural effects should be obtained if DA transmission is decreased by some other means, for example by synthesis inhibition, and that 2) the response to APO should be altered if DA transmission is already lowered.It was found that high doses of -methyl-p-tyrosine (-MPT; 50–200 mg/ kg) did not reduce water intake in thirsty rats, which low doses of APO do. It was further found that pretreatment with -MPT did not alter the response to APO. These results are difficult to reconcile with the DA autoreceptor hypothesis claiming that behavioural effects of low doses of APO are caused by a decreased release of DA. An alternative interpretation is that low doses of APO stimulates a certain population of sensitive postsynaptic D-2 receptors.