Measured and predicted total body water in children with myelomeningocele.

OBJECTIVE: Children with myelomeningocele (MMC) have an altered body composition and an atypical distribution of total body water (TBW). The aim of the present study was to determine the accuracy of current predictive equations, based on bioelectrical impedance analysis (BIA), in determining TBW when compared with measured TBW using deuterium dilution. METHODS: Fourteen children with MMC were measured for whole body BIA and TBW (using deuterium dilution and the Plateau method). Total body water was predicted using equations based on the resistance and characteristic frequency from BIA measurements and heights of subjects. RESULTS: The mean measured TBW was 15.46 +/- 8.28 L and the mean predictions for TBW using equations based on the resistance and characteristic frequency from BIA measurements and heights of subjects were 18.29 +/- 8.41 L, 17.72 +/- 11.42 L and 12.51 +/- 7.59 L, respectively. The best correlation was found using characteristic frequency. The limits of agreement between measured and predicted TBW values using Bland-Altman analysis were large. CONCLUSIONS: The present study suggests that the prediction of TBW in children with MMC can be made accurately using the equation of Cornish et al. based on BIA measurements of characteristic frequency.

Comparison of measured sleeping metabolic rate and predicted basal metabolic rate during the first year of life: evidence of a bias changing with increasing metabolic rate.

OBJECTIVE: To compare measurements of sleeping metabolic rate (SMR) in infancy with predicted basal metabolic rate (BMR) estimated by the equations of Schofield. METHODS: Some 104 serial measurements of SMR by indirect calorimetry were performed in 43 healthy infants at 1.5, 3, 6, 9 and 12 months of age. Predicted BMR was calculated using the weight only (BMR-wo) and weight and height (BMR-wh) equations of Schofield for 0-3-y-olds. Measured SMR values were compared with both predictive values by means of the Bland-Altman statistical test. RESULTS: The mean measured SMR was 1.48 MJ/day. The mean predicted BMR values were 1.66 and 1.47 MJ/day for the weight only and weight and height equations, respectively. The Bland-Altman analysis showed that BMR-wo equation on average overestimated SMR by 0.18 MJ/day (11%) and the BMR-wh equation underestimated SMR by 0.01 MJ/day (1%). However the 95% limits of agreement were wide: -0.64 to +0.28 MJ/day (28%) for the former equation and -0.39 to +0.41 MJ/day (27%) for the latter equation. Moreover there was a significant correlation between the mean of the measured and predicted metabolic rate and the difference between them. CONCLUSIONS: The wide variation seen in the difference between measured and predicted metabolic rate and the bias probably with age indicates there is a need to measure actual metabolic rate for individual clinical care in this age group.

Value of total body potassium in assessing the nutritional status of children with end-stage liver disease.

Malnutrition is a common problem in children with end-stage liver disease (ESLD), and accurate assessment of nutritional status is essential in managing these children. In a retrospective study, we compared nutritional assessment by anthropometry with that by body composition. We analyzed all consecutive measurements of total body potassium (TBK, n = 186) of children less than 3 years old with ESLD awaiting transplantation found in our database. The TBK values obtained by whole body counting of 40K were compared with reference TBK values of healthy children. The prevalence of malnutrition, as assessed by weight (weight Z score < -2) was 28%, which was significantly lower (chi-square test, p < 0.0001) than the prevalence of malnutrition (76%) assessed by TBK (< 90% of expected TBK for age). These results demonstrated that body weight underestimated the nutritional deficit and stressed the importance of measuring body composition as part of assessing nutritional status of children with ESLD.

Resting energy expenditure of children attending a rehabilitation programme following head injury.

STATEMENT OF PURPOSE: Increased resting energy expenditure following head injury is well documented, but whether this increase extends into rehabilitation and whether this is affected by changes in body composition have not been studied. The aim of this study was to determine whether children attending a rehabilitation program following head injury had altered energy expenditure and body composition. METHODS: Measurements of resting energy expenditure by indirect calorimetry were performed in 21 head injured children (mean age 10.2 +/- 3.8 years). Measurement of body composition was performed using total body potassium. RESULTS: Measured resting energy expenditure values were widely distributed, ranging from 52.3-156.4% of predicted values, yet the mean percentage predicted using Schofield weight, Schofield weight and height and World Health Organization predictive equations were 97.5%, 97.4% and 98.6%, respectively. Mean percentage of expected total body potassium for weight, height and age for head injured children were 85.1 +/- 15.5%, 89.1 +/- 14.1% and 86.9 +/- 15.9%, thus all showed significant depletion. CONCLUSIONS: During rehabilitation, using predictive equations to estimate resting energy expenditure in this group revealed a small bias on average but very large bias at the individual level. Head injured children had altered resting energy expenditure and body composition.

Reduced body cell mass following severe head injury in children: implications for rehabilitation.

STATEMENT OF PURPOSE: Increased proteolysis, muscle catabolism and altered body composition have been well documented after severe head injury, but the extent of these effects in children, and whether they extend into rehabilitation, have not been studied. This study determined nutritional status and body composition, with particular reference to the body cell mass (BCM), of head injured children at entry into a rehabilitation programme, and compared body composition analysis with anthropometric nutritional assessment. METHODS: Nineteen head injured children (nine males, 10 females, mean age 9.1 +/- 4.3 years range 1.2-15.1 years) were measured for height, weight and total body potassium (TBK, a measure of body cell mass) on referral to rehabilitation after the acute phase (mean 38.1 days post-injury). Data was compared with expected normative data derived from healthy age and gender matched children. Nutritional status was determined by two separate criteria based on either anthropometric or body composition methods. RESULTS: The mean percentage of expected TBK for height was 84.4 +/- 15%, significantly below the clinically acceptable level for body cell mass (90% of expected). Using the anthropometric definition, only 1/19 was undernourished, whereas 12/19 had poor nutritional status using body composition (chi 2 = 7.58, p = 0.006). CONCLUSIONS: The data revealed a significant depletion in the metabolically active BCM in the presence of normal anthropometry, suggestive of significant muscle wasting. These findings have important pathophysiological and clinical implications in the rehabilitation of children following major head trauma.

The sleep patterns of infants and young children with gastro-oesophageal reflux.

OBJECTIVE: Sleep disturbance in gastro-oesophageal reflux disease (GORD) in infants and young children has not been systematically studied nor has this manifestation been compared with population norms. METHODS: Sleep patterns of 102 infants and children aged 1 to 36 months with and without GORD, defined by pH monitoring, were analysed using the same questionnaire as in recent studies of normal sleep behaviour in this age range. Main outcome measures included time taken to settle at night, the number of night time wakenings requiring parental intervention, day time sleep patterns and parents problems with their childs' sleep behaviour. RESULTS: Compared with the population norms (n=3102), those with GORD (n=76) had greater prevalence of night time waking >3/night (50% vs 13% aged 3-12 months; 60% vs 10% aged 12-24 months, P<0.001), requirement of parental intervention (82% vs 55% aged 3-12 months, P<0.05; 92% vs 55% aged 12-24 months, P<0.001), significantly delayed onset of sleeping through the night, and greater prevalence of daytime sleep beyond 24 months. Similar but less striking differences were seen comparing those with (n=76) and without GORD (n=26). CONCLUSIONS: Sleep interruption occurs more frequently in infants and children with GORD than population norms. Objective evaluation of infants and children with sleep disturbance after the age of 3 months may avoid unnecessary over or under diagnosis of GORD. Systematic investigation of the contribution of GORD to sleep disturbance in infants and young children is warranted.

Lack of sensitivity of weight targets compared with body cell mass for determining recovery from malnutrition in adolescents with anorexia nervosa.

OBJECTIVE: Using body weight targets to assess recovery from malnutrition in adolescents with anorexia nervosa (AN) may lead to premature discontinuation of refeeding programs. We examined body cell mass (BCM) to determine nutritional recovery, comparing with conventional indices based on weight. METHOD: Body mass index (BMI), Z-score, percentage of ideal body weight (IBW), and BCM (by total body potassium) were studied in adolescent females with AN (n = 92). RESULTS: Fourteen percent had "normal" weights (> 85% of IBW), 24% had "acceptable" BMI values (> 16), and 15% had "acceptable" Z-score values (> -1) when their BCM was not fully restored. DISCUSSION: The use of percentage of IBW, Z-scores, or BMI lacks sensitivity in determining adequacy of nutritional rehabilitation. Body compartmental analysis particularly of BCM and body fat is recommended, and the use of BMI particularly should be discarded.

Comparison of effects of adrenalectomy and RU-486 in rats given a choice of maintenance diet and fat supplement.

The effects of adrenalectomy (ADX) and the blockade of glucocorticoid receptors by RU-486 on Sprague-Dawley rats given a choice of a maintenance diet and a fat supplement were studied. Adult male rats were given free access to AIN-76A diet only (CON) or AIN-76A diet and a separate dietary fat option for 4 wk (FAT). They were then assigned to one of the following treatments: ADX, sham operation, ADX with corticosterone (CORT) replacement, RU-486 injections, or vehicle injections. Food intake and body weight were monitored daily for an additional 3 wk. ADX decreased caloric intake and weight gain in the FAT group more than in the CON group. RU-486 also decreased caloric and fat option intakes as well as weight gain. ADX, but not RU-486, reduced body fat content, lowered plasma insulin and triglyceride levels, and decreased glucose intolerance. CORT replacement partially prevented the effects of ADX on weight gain and body fat content. The results of this study indicate that ADX has greater effects on weight gain and body fat accumulation than does RU-486.

An evaluation of the use of total body electrical conductivity for the estimation of body composition in adult rats: effect of dietary obesity and adrenalectomy.

Total body electrical conductance (TOBEC) has been recommended for serial measurements of body composition in animals and humans. This study examined the accuracy of the TOBEC technique in predicting body composition of a population of adult male rats that had undergone seven different treatments, including adrenalectomy and blocking of glucocorticoid receptors, in the study of the etiology of obesity. The predicted body composition values of the animals (n = 57, body weight 550 +/- 8 g) obtained by using the manufacturer's and Baer's equations were compared to the actual body composition obtained by direct carcass analysis. Both equations underestimated lean body mass and reciprocally overestimated body fat (manufacturer's 103 +/- 4 g, Baer's 55 +/- 3 g). A new prediction equation was developed based on the conductivity index and the actual lean body mass. This revised equation was able to accurately estimate the lean body mass of the animals used in the same experiment but over-estimated lean body mass of larger animals (n = 10, wt. 647 +/- 13 g). Conclusions based on multiple comparisons (Duncan's) of predicted and actual values resulted in different effects of treatments on body composition. To improve accuracy and reliability of the TOBEC technique, a prediction equation should be developed from the same population as the studied population, and experimental group sizes used for examining treatment effects should be relatively large.

A longitudinal study of urinary calcium, magnesium, and zinc excretion in lactating and nonlactating postpartum women.

Postpartum lactating (n = 12) and nonlactating (n = 11) women and never pregnant women (n = 14) collected urine samples and diet records 2 d each month for 6 mo to determine whether postpartum women conserved urinary calcium, magnesium, or zinc. Mean daily excretions were analyzed by repeated-measures analysis of variance and covariance to assess group and time effects. Lactating women excreted less urinary calcium (1-6 mo) than never pregnant (n = 8) and nonlactating (n = 4) women who did not use oral contraceptives (P < 0.01); however, excretion rose (P < 0.05) by 3 mo postpartum. In the nonlactating and never pregnant groups, women using oral contraceptives excreted less urinary calcium than the other women (P < 0.01). Lactating women excreted less urinary zinc (1-6 mo) than did control and non-lactating women (P < 0.01). Mechanisms may possibly be operating during lactation that depress urinary calcium for > or = 2 mo and urinary zinc < or = 6 mo postpartum.

Evaluation of early enteral feeding in children less than 3 years old with smaller burns (8-25 per cent TBSA).

Early enteral feeding and high protein nutrition have been advocated for burned patients. The safety and efficacy of early high protein nasogastric feeding (NG) have not been evaluated in very young children. The present study evaluated such feeding in children less than 3 years old with smaller burns (8-25 per cent of total body surface area). Children (n = 10) were able to tolerate high protein intake without detrimental effects. The incidences of gastrointestinal complications related to NG feeding were low. The children needed approximately 2 weeks of supplemental NG feeding which provided two-thirds of total energy intake and three-fourths of protein intake. In spite of smaller burns, the mean measured resting metabolic expenditure (REE) was 1.3 x predicted REE. The mean energy intake of 92 per cent of recommended daily allowances (RDA) for energy or 1.7 x predicted REE was able to maintain body weight. The mean protein intake was 4.3 g/kg/day with a non-protein calorie ratio of 114:1. During the first week postburn, plasma concentrations of prealbumin, albumin and transferrin were low. The high protein intake was able to raise these visceral proteins to normal ranges. These results indicate that early NG feeding is safe and efficacious for achieving increased energy intake and improved protein status in very young children.

Protracted infusion of 5-FU with weekly low-dose cisplatin as second-line therapy in patients with metastatic colorectal cancer who have failed 5-FU monotherapy.

Forty four patients who had documented progression of metastatic colorectal cancer while receiving 5-fluorouracil (5-FU) monotherapy were treated with continuous infusion 5-FU, 300 mg/mg2/day, plus weekly low-dose cisplatin, 20 mg/m2. Treatment was given in 12-week cycles, consisting of 8 weeks of chemotherapy followed by a 4-week rest period, and was well tolerated. Three of 23 patients (13%) who had failed bolus 5-FU but not been exposed previously to infusional 5-FU responded. Of 21 patients who had failed infusional 55-FU monotherapy, only one (5%) responded. Time to progression (5.7 vs. 1.8 months) and survival (12 vs. 5.5 months) were significantly longer for patients who had not previously received infusional 5-FU but who had failed bolus schedules, compared with patients who had previously failed infusional 5-FU (p less than .001).

Effect of vitamin A in enteral formulae for burned guinea-pigs.

A burned guinea-pig model (30 per cent body surface area) was used to study the effects of dietary vitamin A. Sixty-five female guinea-pigs were infused enterally via gastrostomy feeding tubes with identical formulate (175 kcal/kg/day, 20 per cent of calories as protein) containing varying amounts of vitamin A. Groups I, II, III and IV received formulae containing 0, 10,000 iu (approximately equivalent to the guinea-pigs' RDA), 50,000 iu (5 x RDA) and 250,000 iu (25 x RDA) of vitamin A per litre, respectively. After 14 days of tube feeding, the animals were killed. Group I animals had evidence of vitamin A deficiency including low haemoglobin levels, lower red blood cell counts and lower caecal mucosal weight. Findings of hypervitaminosis A were observed only in animals given the highest dose of vitamin A (25 x RDA). These were elevated serum alkaline phosphatase and complement C3 levels and enlarged adrenal glands. Group IV also showed defective cell-mediated immunity as reflected by reduced delayed cutaneous response to dinitrofluorobenzene. In a second experiment groups I, II, III and IV were given formulas containing 0, 1 x RDA, 5 x RDA, and 10 x RDA of vitamin A respectively for 14 days. Through postburn days 12 to 14 they were injected subcutaneously with 3 x 10(8) of Staphylococcus aureus once daily. On postburn day 15 the animals were killed and the numbers of viable bacteria at each injection site were counted. No significant differences were observed in viable bacterial numbers between the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevention of yeast translocation across the gut by a single enteral feeding after burn injury.

Recently, burn injury has been shown to facilitate the ability of enteric Candida albicans (CA) to penetrate the gut epithelium and translocate to the mesenteric lymph nodes (MLN) during the first 24 hr after injury. Guinea pigs were given 3 X 10(10) CA intragastrically before inflicting a 50% burn to determine if a single enteral feeding could affect CA translocation to the MLN. A bolus infusion (20 kcal/kg, 12 ml in volume) of liquid meal, consisting of 68% carbohydrate, 20% protein, and 12% lipid, was administered either at 3-hr or 12-hr postburn. Control groups received no food or a similar amount of saline by bolus infusion. All animals were allowed water ad libitum until 24-hr postburn when their MLN and intestinal segments were harvested for enumeration of viable CA. Blood was also collected for determination of serum IgG, C3, cortisol, and albumin. Compared to nonfeed animals, those with a single enteral feeding at 12-hr postburn had reduced numbers of CA translocating to the MLN (970 +/- 220 vs 7,120 +/- 2,130 CFU/g, p less than 0.02) and colonizing in the ileum (27,000 +/- 6,770 vs 104,000 +/- 23,550 CFU/g, p less than 0.01). Bolus feeding at 12 hr was associated with a lower cortisol level (237 +/- 55% of normal controls) than bolus feeding at 3 hr (310 +/- 58, p less than 0.02) or the nonfed group (326 +/- 66, p less than 0.01). Regardless of dietary treatment, serum cortisol levels correlated positively with the extent to which CA translocated to the MLN and negatively with C3 levels.

Increased gut blood flow with early enteral feeding in burned guinea pigs.

The hemodynamic responses to early enteral feeding were assessed with fluid-resuscitated, 30% total body surface area-burned guinea pigs fed by means of tube gastrostomies. Regional blood flow and cardiac output were determined by a reference sample method, injecting 15 microns radiolabeled microspheres. During the initial 24 hours after burn injury, animals were given the same volume by continuous infusion of either lactated Ringer's solution (LR group) or a liquid diet (20% protein, 12% lipid, and 68% carbohydrate; 175 kcal/kg/24 hr) (diet group). Although cardiac outputs in the LR and diet groups were not different from each other at 24 hours and no less than that in unburned control animals, the diet group showed higher blood flow to the jejunum (+55.7%) and cecum (+98.7%) than did the LR group. Burn injury caused little change of blood flow to tissues other than the intestine. In addition, early feeding after burn injury suppressed excessive cortisol response to burn shock. The increase in gut blood flow associated with enteral feeding could have an impact on mucosal barrier function.

Carnitine supplementation vs. medium-chain triglycerides in postburn nutritional support.

The effect of dietary supplementation of carnitine on protein metabolism was studied in a burned guinea-pig model. Animals bearing a 30 per cent total body surface area burn were enterally infused with three isocaloric and isonitrogenous diets via gastrostomy feeding tubes for 14 days. Two diets contained safflower oil (long-chain triglycerides, LCT) and another diet contained medium-chain triglycerides (MCT) as their lipid sources (30 per cent of total calories as lipid). L-Carnitine was added to one of the two diets containing safflower oil. There were no significant differences in nitrogen balance, urinary excretion, serum albumin or transferrin among the three groups. However, the use of MCT in place of LCT appeared to increase liver weight and liver nitrogen. In this model, carnitine supplementation did not enhance the nitrogensparing effect of fat following burn injury.

Candida albicans translocation across the gut mucosa following burn injury.

Normal guinea pigs were challenged intragastrically with Candida albicans 1 hr prior to a 30 or 50% flame burn to determine if burn injury increased translocation of the yeasts across gut mucosa. Tissues were harvested between 3 and 24 hr postburn and cultured on Sabouraud dextrose agar. Control animals (no yeast challenge) showed no yeast in intestinal homogenates or in the mesenteric lymph nodes (MLN). At a dose of 1 X 10(9) yeasts, they did not escape from the gut lumen, with either a 30 or 50% burn. At a dose of 2 to 4 X 10(10) organisms, they translocated to the MLN in 92% of the 50%-burned animals (P less than 0.001), 75% of the 30%-burned animals (P less than 0.05), and 12.5% of unburned animals. The ileal mucosa appeared to be the most susceptible site for yeast invasion. To observe the penetration through the gut mucosa and/or translocation to other tissues, yeasts were labeled with biotin before administration, and tissues were stained with avidin-peroxidase diaminobenzidine sequence. With biotinylated yeasts, phagocytized organisms were observed in large numbers in the lamina propria and mesenteric lymph nodes but they were not viable upon culture. Toluidine blue staining of semithin sections revealed that translocated yeasts were located selectively in the lymphoid follicles of the MLN, entrapped by macrophages.