Enteral feeding in burn hypermetabolism: nutritional and metabolic effects of different levels of calorie and protein intake

Enteral nutrition was provided by continuous pump-controlled gastrostomy tube feeding for 14 days in 97 guinea pigs bearing a 30% full thickness burn. Seven defined combinations of caloric and protein intake were studied. With a caloric intake of 175 kcal/kg/day, equaling the measured energy expenditure, the animals receiving 10% of calories as protein had a significantly greater postburn weight loss (p less than 0.05) and muscle mass depletion (p less than 0.05), and a significantly lower muscle nitrogen concentration (p less than 0.05), serum albumin level (p less than 0.01) and liver nitrogen content (p less than 0.01). With the same caloric intake but with more than 20% of calories as protein, the weight loss and the muscle wasting were reduced, but not abolished, and the serum albumin level and liver nitrogen content were normalized. Also with the diets containing 200 kcal/kg/day the muscle tissue depletion could not be abolished. However, with this caloric intake, the animals given 20% of calories as protein had a lower weight loss and a higher serum albumin level (p less than 0.01), but also a greater fat infiltration of the liver (p less than 0.01). At both levels of caloric intake, the nitrogen balance correlated significantly with the level of nitrogen intake but did not correlate with the changes of body weight. The incidence of diarrhea was lowest in animals fed 20% protein calories at a caloric intake of 175 kcal/kg/day. All things considered, the best metabolic and nutritional results were obtained with diets containing 20 to 30% of calories as protein and providing a caloric intake that paralleled the measured energy expenditure.     

Nonlipid formula components and fat absorption in the low-birth-weight newborn

The relationship between nonlipid formula components and fat absorption in newborns is largely uninvestigated. Two formulas of identical fat blend but different protein quality and acid-base properties were fed to two groups of babies from birth and during 3-5 d balance periods in the third week of life. Babies receiving a formula of higher acidity containing predominantly curd protein absorbed a significantly lower percentage of their fat and nitrogen intake than babies receiving a curd-and-whey protein formula (fat absorptions of 73 +/- 11.0 and 85 +/- 8.0%, means +/- SD, p less than 0.04; N absorptions of 90 +/- 3.0 and 93 +/- 1.0%, p less than 0.03, respectively). The feces of the curd-formula babies contained a smaller proportion of long-chain, saturated fatty acids and a larger proportion of shorter-chain and unsaturated fatty acids. Fatty acid type and triglyceride structure are not the only factors influencing fat absorption in newborns. Other formula components may need modification to achieve maximum fat absorption.     

Dietary fat and natural-killer-cell activity

An intervention trial designed to lower the amount of fat in the diet was conducted to test the effect of reduced fat consumption (LF diet) on activity of natural killer (NK) cells in humans. Of 26 men enrolled initially, 17 successfully completed the intervention and lowered their fat intake to less than 30% of calories as fat. Data were analyzed in two ways. The paired t test showed a marked increase in NK-cell activity from baseline to the end of the LF-diet intervention (t = 4.77, p = 0.0002). Results of a general linear model showed an effect of lowering total dietary fat on increased NK-cell activity (approximately 0.53% increase for each absolute percent of calories as fat, p = 0.14) for all men and a highly significant effect in a subset of men who ate greater than 25% of calories as fat at baseline (approximately 1.22% increase, p = 0.009). These results were obtained after changes in total caloric intake, weight, exercise, and other fat-related covariates were accounted for.     

Epidemiology of rotavirus and cholera in children aged less than five years in rural Bangladesh

Despite the known presence of rotavirus-associated diarrhoea in Bangladesh, its prevalence, including records of hospitalization in rural health facilities, is largely unknown. In a systematic surveillance undertaken in two government-run rural health facilities, 457 children, aged less than five years, having acute watery diarrhoea, were studied between August 2005 and July 2007 to determine the prevalence of rotavirus. Due to limited financial support, the surveillance of rotavirus was included as an addendum to an ongoing study for cholera in the same area. Rotavirus infection was detected in 114 (25%) and Vibrio cholerae in 63 (14%) children. Neither rotavirus nor V cholerae was detected in 280 (61%) samples; these were termed 'non-rotavirus and non-cholera' diarrhoea. Both rotavirus and cholera were detected in all groups of patients (<5 years). The highest proportion (41%; 47/114) of rotavirus was in the age-group of 6-11 months. In children aged less than 18 months, the proportion (67%; 76/114) of rotavirus was significantly (p < 0.001) higher than that of cholera (16%; 10/63). By contrast, the proportion (84%; 53/63) of cholera was significantly (p < 0.001) higher than that of rotavirus (33%; 38/114) in the age-group of 18-59 months. During the study period, 528 children were hospitalized for various illnesses. Thirty-eight percent (202/528) of the hospitalizations were due to acute watery diarrhoea, and 62% were due to non-diarrhoeal illnesses. Rotavirus accounted for 34% of hospitalizations due to diarrhoea. Severe dehydration was detected in 16% (74/457) of the children. The proportion (51%; 32/63) of severe dehydration among V cholerae-infected children was significantly higher (p < 0.001) compared to the proportion (16%; 18/114) of rotavirus-infected children. The study revealed that 12-14% of the hospitalizations in rural Bangladesh in this age-group were due to rotavirus infection, which has not been previously documented.     

Nutrient and food intake in obese women on a low-fat or low-calorie diet

The low-fat group consumed significantly fewer calories from fat and more calories from carbohydrate at both 6 and 12 months than the low-calorie group, but their fat intake was still about twice their goal at both 6 months (39 gm per day) and 12 months (46 gm per day). The low-calorie group achieved their fat goal of 30% of calorie intake, but they consumed from 300 to 700 kcal more than their calorie goal. Caloric intake, physical activity, palatability, satiety, quality of life, and weight loss were not significantly different by treatment. Two studies, which gave patients hypocaloric diets of varying fat and carbohydrate content (fat calories 10% to 45%) for from 10 to 12 weeks, found no effect of diet composition on weight loss. In addition, one study, which gave patients a low-fat, energy-unrestricted diet (fat calories 19%), reported a weight loss of 10.1 lb at 16 to 20 weeks and 5.7 lb at 9 to 12 months, which is similar to that seen in the low-fat group in the this study. Most of the decrease in fat intake (90%) in the low-fat group resulted from a reduction in intake of fat from fat and oils; meat, fish, and poultry; dairy products; and sweets. The dietary changes in the low-fat group are consistent with those found in one study, which prescribed a 15% fat calorie diet to women with breast cancer. Intake of vitamin C increased in the low-fat group and decreased in the low-calorie group. This difference was significant and was caused by an increased intake of fruits and vegetables in the low-fat group and a decreased consumption of fruits in the low-calorie group. Calcium intake decreased significantly more in the low-calorie group because of a decreased intake of dairy foods.     

Stage-matched nutrition guidance: stages of change and fat consumption in Dutch patients at elevated cardiovascular risk

OBJECTIVE: To assess the effects of stage-matched nutrition counseling on stages of change and fat intake. DESIGN: Controlled clinical trial. SETTING: 9 family practices in a family medicine practice network. PARTICIPANTS: 143 patients at elevated cardiovascular risk, aged 40 to 70 years. INTERVENTION: Intervention patients received stage-matched counseling from their family physician and a dietitian. Control patients received usual care. MAIN OUTCOME MEASURES: Stages of change and fat intake were measured at baseline and after 6 and 12 months. ANALYSIS: Chi-squared tests, t tests, and regression analyses (alpha = .05) were conducted. RESULTS: More patients in the intervention group than in the control group were in the postpreparation stage after 6 months (70% vs 35%; P < .01) but not after 12 months (70% vs 55%; P = .10). Between 0 and 12 months, the reduction in total fat intake (-5.6% kcal vs -2.4% kcal) was largest in the intervention group. CONCLUSIONS AND IMPLICATIONS: Stage-matched nutrition counseling promotes movement through stages of change, resulting in a reduced fat intake. Our results partly support stages of change as a tool for behavior change. Movement across stages of change was not an intermediating factor in the intervention effects. Research should focus on feasible ways to keep patients in the postpreparation stage.     

Nutritional intake of gut failure patients on home parenteral nutrition

Nutrient intake patterns were analyzed in 23 patients with gut failure who were receiving home parenteral nutrition (HPN). All patients had stable weights without changes in intravenous calories or protein for 3 consecutive months. Our objectives were to assess oral intake of calories, carbohydrates, fat, and protein, to examine relationships between oral nutrient intakes and disease categories, and to compare oral and intravenous intakes to calculated resting energy expenditure (REE). Two patterns of oral nutrient intake were identified among the patients. Patients with short bowel syndrome, regardless of the underlying disease, consumed calories by mouth that clearly exceeded calculated resting energy expenditure (short bowel, non-Crohn's, 170% of REE; short bowel, Crohn's, 200 of REE); however, calories approximating the REE had to be given via HPN, suggesting that efficiency of absorption was at a very low level. Patients with diffuse gut diseases (radiation enteritis or pseudo-obstruction syndromes) had very low intakes of oral nutrients. The distribution of oral calories among carbohydrate, protein, and fat did not differ among the disease categories.     

Stages of Change and Reduction of Dietary Fat: Effect of Knowledge and Attitudes in an Australian University Population

This survey focused on the use of the stages of change model of behavior change in reducing dietary fat intake while identifying attitudinal variables that might be relevant in the decision to change one's dietary habits. Knowledge of dietary fat and reported fat intake were also examined. Data were obtained using a cross-sectional survey of 1081 university employees. The Precontemplation stage comprised the largest group of respondents (33%) while the Contemplation stage was the smallest group, containing only 6% of respondents. Twelve percent of respondents were in the Preparation stage while the Action and Maintenance groups comprised 22% and 27% of the total population, respectively. Two one-way multivariate analyses of variance were used to compare male and female respondents across the five stages of change on knowledge, dietary fat intake, benefits, and barriers. Dietary fat intake and barriers to reducing fat intake decreased significantly across the stages of change while the benefits to change increased significantly across the stages. The results of our study confirm differences in stages of change in fat intake and indicate the need for taking these phases of change into account in nutrition advice.     

A controlled trial of fixed versus tailored calorie intake in patients receiving intravenous feeding after abdominal surgery

Excessive intravenous calorie intakes have been shown to increase fat deposition and CO2 production with deleterious results. A controlled trial has therefore been performed to determine whether there is clinical benefit from tailoring calorie intake of intravenously fed patients to the patient's metabolic expenditure. Twenty patients requiring intravenous feeding after abdominal surgery were randomly allocated to receive either (i) a constant regimen containing 2 600 calories and 15.55 g nitrogen or (ii) a varied regimen with a fixed calorie: N2 ratio of 167:1 but with the calorie intake adjusted according to the previous day's metabolic expenditure. Only one patient had a requirement of greater than 2 600 calories; there was no difference in mean RQ during intravenous feeding between the constant regimen (0.90 +/- 0.10 s.d.) and the varied regimen (0.90 +/- 0.09 s.d.) and no significant difference in peak CO2 production. Excess calorie intake over expenditure did not correlate with increased positive nitrogen balance but on the varied regimen patients receiving a higher nitrogen intake tended to be in more positive nitrogen balance. This study suggests that a fixed calorie intake of 2 600 calories per day is suitable for adult patients requiring intravenous feeding after abdominal surgery but currently prescribed nitrogen intakes may be suboptimal.     

Dietary assessment of older Iowa women with a food frequency questionnaire: nutrient intake, reproducibility, and comparison with 24-hour dietary recall interviews.

The authors report the results of a dietary survey of 38,121 Iowa women, 55-69 years of age in 1986, based on a semiquantitative food frequency questionnaire previously tested among Boston-area women aged 34-59 years. The Iowa women, compared with the younger Boston-area women, consumed a similar amount of calories (1,767 vs. 1,844 kcal) and a similar amount of total calories from fat (35 vs. 37%) but had markedly greater intake of the following micronutrients after including supplement use: iron (+18%), calcium (+33%), vitamin A (+43%), riboflavin (+46%), thiamine (+50%), and pyridoxine (+122%). The reproducibility of the questionnaire was examined in two more administrations to 44 of the Iowa women in January and June of 1988. Reproducibility was highest for alcohol (Pearson's r = 0.99), caffeine (r = 0.95), and vitamin E (r = 0.90) and lowest for sucrose (r = 0.53), polyunsaturated fat (r = 0.56), and iron (r = 0.59). Micronutrient intakes were generally more reproducible than macronutrient intakes. The agreement between the June 1988 questionnaire and the average of five 24-hour dietary recalls was also assessed in the 44 subjects. The median correlations of energy-adjusted intake were as follows: for macronutrients, r = 0.45; for micronutrients without supplements, r = 0.33; and for micronutrients with supplements, r = 0.64. This food frequency questionnaire appears to be reasonably reproducible and accurate, so that its use may be extended to epidemiologic studies of older women with a broad range of socioeconomic backgrounds.     

肝移植术后早期的营养支持

目的:探讨肝移植术后早期的营养支持.方法:将44例肝移植术后病人随机分为相对高能量组(A组)和相对低能量组(B组),每组各22例.观察其术后3周内氮平衡、体质量、血清清蛋白及血红蛋白、血脂、肾功能、肝功能的变化情况.结果:两组的体质量、血清清蛋白及血红蛋白、肝功能指标等差异无显著性意义;A组的氮平衡明显优于B组,肾功能明显差于B组.结论:肝移植术后早期营养供给量应适当控制.     

Parenteral nutrition and oral intake: effect of glucose and fat infusions

The effect of intravenous nutrition on voluntary oral intake was studied in healthy male volunteers. Subjects were confined to the Surgical Metabolic Unit for the 17 to 19 day study and were restricted to commercial liquid diet. Each study consisted of three consecutive phases: (1) Ringer's lactate (RL), (2) peripheral parenteral nutrition (PPN) administered for 5 or 6 days as a combination of glucose (caloric load equal to 34% resting energy expenditure, REE), fat (34% REE), and amino acids (17% REE) or a single nutrient infusion of glucose (68% REE), fat (68% REE), glucose (34% REE), or fat (34% REE), and (3) RL for the third period. When all three nutrients or glucose alone (68% REE) were given, subjects decreased daily voluntary food intake within 24 to 48 hr by an amount that closely compensated for the infused calories. Intake was reduced by only 20% to 40% of the infused calories when fat alone (68% REE) was given. There were no significant effects when the lower levels of glucose and fat were given. These data suggest the presence of a postabsorptive control of food intake in humans that is sensitive to the circulating supply of fuels.     

The effects of varying dietary fat on performance and metabolism in trained male and female runners

OBJECTIVES: Low dietary fat intake has become the diet of choice for many athletes. Recent studies in animals and humans suggest that a high fat diet may increase VO2max and endurance. We studied the effects of a low, medium and high fat diet on performance and metabolism in runners. METHODS: Twelve male and 13 female runners (42 miles/week) ate diets of 16% and 31% fat for four weeks. Six males and six females increased their fat intakes to 44%. All diets were designed to be isocaloric. Endurance and VO2max were tested at the end of each diet. Plasma levels of lactate, pyruvate, glucose, glycerol, and triglycerides were measured before and after the VO2max and endurance runs. Free fatty acids were measured during the VO2max and endurance runs. RESULTS: Runners on the low fat diet ate 19% fewer calories than on the medium or high fat diets. Body weight, percent body fat (males=71 kg and 16%; females=57 kg and 19%), VO2max and anaerobic power were not affected by the level of dietary fat. Endurance time increased from the low fat to medium fat diet by 14%. No differences were seen in plasma lactate, glucose, glycerol, triglycerides and fatty acids when comparing the low versus the medium fat diet. Subjects who increased dietary fat to 44% had higher plasma pyruvate (46%) and lower lactate levels (39%) after the endurance run. CONCLUSION: These results suggest that runners on a low fat diet consume fewer calories and have reduced endurance performance than on a medium or high fat diet. A high fat diet, providing sufficient total calories, does not compromise anaerobic power.     

How much dietary fat in therapeutic nutrition?

Dietary fat has a less prominent role in realimentation than the alternate source of energy, carbohydrate. Presently available therapeutic diets, in typical feeding routines, provide only 3 to 120 g of fat per day. Three major factors contribute to fat underutilization: long-standing belief that fat is to blame for various vague symptoms of indigestion, misconception that daily fecal fat in excess of 7 g represents bowel dysfunction, and fear of fat-induced atherogenesis. None of these apply to refeeding starved and malnourished patients. The small intestine has a vastly underutilized capacity for fat absorption, and at the habitual fat intake of 100 g per day absorption is complete in the proximal one fifth of the gut. In patients requiring vigorous realimentation, the remaining small intestine should also be utilized. Dietary fat is well tolerated, and daily intakes of 500 g of polyunsaturated fat in a complete diet have not been associated with important side effects, while there was a significant improvement in body stores of fat and protein. Compared to diets high in carbohydrate, adequate intake of fat results in better nutrient utilization, less CO2 production and decreased lipogenesis and insulin requirements. Diets higher in fat are also better tolerated because of their lower volume and osmolality. The result is more effective absorption of calories and a faster nutritional recovery. Increased adipose tissue and protein reserve benefits patients who are in stress, immunocompromised, or debilitated. Adequate dietary fat should be considered for malnourished subjects with intact gastrointestinal function, and when intestinal absorptive capacity is reduced by surgery or disease.     

Is it possible to evaluate the efficacy of amino acid solutions after major surgical procedures or accidental injuries? Evaluation in a randomized and prospective study

Two unbalanced amino acid solutions (essential amino acids, branched-chain amino acids) were compared to a complete and balanced amino acid solution with regard to efficacy of nitrogen balance. Patients were randomized to receive the amino acid solutions over 3 days for each regimen. The patients were examined postoperatively or directly after accidental trauma. Nonprotein calories were given as 40 kcal/kg/day consisting of 50% fat and 50% glucose. Nitrogen was given at the amount of 0.15 g N/kg/day. Unbalanced amino acid solutions gave a 2-fold more negative nitrogen balance than a balanced and complete amino acid solution. However, this difference disappeared and nitrogen balance approached equilibrium irrespective of the amino acid composition of the infused solutions when nitrogen in blood products was accounted for. All patients received a considerable amount of blood products in a comparable but unpredictable way. Blood products corresponded to around 40% of the daily nitrogen intake. Our study demonstrates that it is not possible to test the efficacy of amino acids for nitrogen retention in patients who are in the need of blood-product transfusions. It is likely that amino acids in blood proteins serve as a significant amino acid source that is utilized for resynthesis of body proteins especially in flow-phase patients with high protein breakdown. This fact has not been sufficiently accounted for in the previous literature.     

Nitrogen balance in obese patients receiving a very low calorie liquid formula diet.

Eleven obese patients were placed on a liquid formula diet containing 320 kcal (1.34 MJ), 31 g protein, 44 g oligosaccharides, 1.5 g fat, vitamins, and essential minerals for a period of 4 weeks under metabolic ward conditions. The diet was well tolerated, and mean weight loss was 2.49 kg/week during the 4-week period. Nitrogen excretion diminished in all patients during the period of treatment, but nitrogen balance remained slightly negative in most patients, mean daily deficit being 1.3 g N/day at the end of the study. The rate at which nitrogen was loss declined in a biphasic fashion, a slower second phase after an initial rapid period of adjustment to the diet. During the study a mean of 4.1 +/- 1.4% SD of calculated total body nitrogen was lost. Potassium excretion studies did not reveal significant potassium losses. The amount of nitrogen loss was correlated with the urinary creatinine excretion, suggesting that nitrogen loss during reduced dietary intake of protein is largely dependent on the size of the lean body mass.     

杭州地区腹泻患儿轮状病毒感染流行病学特征分析

【目的】 探讨杭州地区腹泻儿童感染A组轮状病毒的流行病学特征,指导临床防治。 【方法】 对2007-2011年门诊和住院的急性腹泻儿童的大便进行轮状病毒抗原检测,并采用统计方法分析流行病学特征。 【结果】 杭州地区2007-2011年腹泻儿童A组轮状病毒平均阳性率为29.25%。阳性率从2007年的39.42%下降到2011年的19.61%,其中每年11-12月份为儿童轮状病毒感染高峰期;且以6~18月的患儿感染率最高。腹泻儿童中门诊轮状病毒阳性率为32.28%,住院儿童的阳性率为20.70%。 【结论】 杭州地区儿童A组轮状病毒感染率低于全国平均水平,而且有逐年下降趋势。在今后应加快安全高效的轮状病毒疫苗的开发,从根本上解决儿童轮状病毒的危害。     

2004年肠道门诊期间其他感染性腹泻病原学监测

目的 探索引起儿童其他感染性腹泻的主要病原体的流行病学特征，提出相应的防制方法。方法 选取医院网络直报的其他感染性腹泻实验室诊断病例，比较各种病原体在地区、性别、年龄之间所占构成比的差异，以及流行的季节性。结果 引起儿童其他感染性腹泻的主要病原体是轮状病毒和空肠弯曲菌，构成比分别是30．89％、69．02％;两者的感染构成比无地区、性别的差异，年龄方面其中轮状病毒6个月～2岁易感，而空肠弯曲菌6个月以内易感；季节方面轮状病毒入秋后流行，空肠弯曲菌春夏季流行。结论 降低儿童其他感染性腹泻主要防制轮状病毒和空肠弯曲菌，研制高效安全的疫苗。     

Obesity management in primary care: assessment of readiness to change among 284 family practice patients

BACKGROUND: Most adults in primary care are overweight or obese; two thirds of patients with weight problems have other obesity-related conditions. The study objective was to explore the feasibility of a primary care obesity intervention based on the transtheoretical model (TM) of behavior change and principles of chronic disease (CD) care. METHODS: A prospective study of the initial version of the TM-CD intervention with obese family practice patients (n = 284) yielded cross-sectional data on baseline stage of change for six target behaviors: dietary fat, portion control, vegetable intake, fruit intake, usual physical activity, and planned exercise. The sample consisted of obese patients scheduled for an office visit during times when recruitment and informed consent did not conflict with acute care. RESULTS: Obese patients volunteering for a TM-CD program are in different stages of change for six target behaviors. Preparation was the most frequently reported stage for increased exercise (49%) or activity (34%), decreased dietary fat consumption (44%), and increased portion control (51%). Patients in a particular stage for one behavior were distributed across all five stages for another behavior. Stage of change for five target behaviors was associated with body mass index or waist girth (P < .05) in a manner consistent with stage-of-change theory. CONCLUSIONS: Using the transtheoretical model of behavior change will allow physicians to recognize when obese patients are receptive to specific behavioral interventions.     

Weight loss on a low-fat diet: consequence of the imprecision of the control of food intake in humans

This study examined the degree to which humans compensate for a reduction in dietary fat by increasing energy intake. Thirteen females were randomly assigned to either a low-fat diet (20-25% of calories as fat) or a control diet (35-40% fat) for 11 wk. After a 7-wk washout period, the conditions were reversed for another 11 wk. Energy intake on the low-fat diet gradually increased by 0.092 kJ/wk resulting in a total caloric compensation of 35% by the end of the 11-wk treatment period. This failure to compensate calorically on the low-fat diet resulted in a deficit of 1.22 kJ/d and a weight loss of 2.5 kg in 11 wk, twice the amount of weight lost on the control diet. These results demonstrate that body weight can be lost merely by reducing the fat content of the diet without the need to voluntarily restrict food intake.