Fernanda Valente Mendes Soares

Freezing and thawing effects on fat, protein, and lactose levels of human natural milk administered by gavage and continuous infusion

OBJECTIVES to analyze the changes in human milk macronutrients: fat, protein, and lactose in natural human milk (raw), frozen and thawed, after administration simulation by gavage and continuous infusion. METHOD an experimental study was performed with 34 human milk samples. The infrared spectrophotometry using the infrared analysis equipment MilkoScan Minor® (Foss, Denmark) equipment was used to analyze the macronutrients in human milk during the study phases. The analyses were performed in natural (raw) samples and after freezing and fast thawing following two steps: gavage and continuous infusion. The non-parametric Wilcoxon test for paired samples was used for the statistical analysis. RESULTS the fat content was significantly reduced after administration by continuous infusion (p<0.001) during administration of both raw and thawed samples. No changes in protein and lactose content were observed between the two forms of infusion. However, the thawing process significantly increased the levels of lactose and milk protein. CONCLUSION the route of administration by continuous infusion showed the greatest influence on fat loss among all the processes required for human milk administration.

Indirect calorimetry: a tool to adjust energy expenditure in very low birth weight infants

OBJECTIVE To determine the resting metabolic rate in very low birth weight infants through indirect calorimetry. METHODS Cross-sectional study including 29 clinically stable very low birth weight infants receiving an enteral diet > 100 kcal/kg/day. Malnutrition was defined as weight-for-age z score < or = - 2 SD. Resting energy expenditure was measured using open circuit indirect calorimetry. RESULTS At the time of the examination, mean weight was 1,564+/-393 g and corrected gestational age was 35+/-3 weeks. Malnutrition was diagnosed in 62.1% of the preterm infants. The mean resting metabolic rate was 57.01+/-7.76 kcal/kg/day. CONCLUSION Since resting energy expenditure is the main caloric component of total energy expenditure, the high resting metabolic rate observed may have a strong impact on the development of malnutrition during hospitalization.

Energy expenditure in very low birth weight newborns: a comparison between small and appropriate-for-gestational-age.

Aims:  To compare resting energy expenditure (REE) in small‐ and appropriate‐for‐gestational‐age very low birth weight newborns after reaching corrected at‐term age.

Antropometria e composição corporal de recém-nascidos pré-termo na idade gestacional e no peso equivalente ao termo

OBJETIVO: Analisar o crescimento e a composicao corporal de recem-nascidos pre-termo na idade gestacional corrigida de termo e ao alcancarem um peso entre 3,0 e 3,5 kg. METODOS: Estudo longitudinal, realizado no Instituto Fernandes Figueira, Rio de Janeiro, com 39 recem-nascidos pre-termo e que apresentaram muito baixo peso ao nascer. Medidas antropometricas e agua corporal total foram avaliadas no primeiro, no setimo e no dia da recuperacao do peso de nascimento, na idade gestacional corrigida do termo e em torno de tres semanas de idade gestacional corrigida (correspondente ao tempo de vida para alcancar um peso entre 3,0 e 3,5 kg). O grupo de referencia foi constituido por 32 recem-nascidos a termo, adequados para a idade gestacional, avaliados no segundo dia de vida. Considerou-se restricao de crescimento o escore-Z menor do que -2 para peso, comprimento e perimetro cefalico. RESULTADOS: Na idade de termo, 71,8% dos recem-nascidos pre-termo apresentaram restricao do crescimento para peso, 61,5% para comprimento e 25,6% para perimetro cefalico. Com tres semanas de idade gestacional corrigida, esses recem-nascidos apresentaram a prega cutânea tricipital e a circunferencia abdominal estatisticamente maiores que o grupo de referencia enquanto o comprimento e a porcentagem de agua corporal total foram menores. CONCLUSAO: Os recem-nascidos pre-termo apresentaram perfil antropometrico e de agua corporal diferente dos recem--nascidos a termo, sugerindo acumulo de gordura. Houve recuperacao do crescimento entre a idade de termo e tres semanas de idade corrigida, sendo mais evidente esse crescimento em relacao ao perimetro cefalico e peso.

Body composition in preterm infants with intrauterine growth restriction: a cohort study

Abstract Aims: The comparison of body composition parameters between the small for gestational age (SGA) and appropriate for gestational age (AGA) at term, 1, 3 and 5 months corrected ages in very preterm infants. Methods: This cohort study included 92 preterm infants at term age, younger than 32 weeks or <1500 g, classified in two groups: SGA and AGA. Anthropometry and body composition, estimated by air displacement plethysmography, were evaluated at the corrected ages: term and 1, 3, and 5 months. We used the lean mass/fat mass index (LM/FM) at each time point and the weight, length and head circumference SDS gain between the time points. Results: At term age, the SGA preterm infants had less lean mass (g), fat mass (g) and percent fat mass but a greater LM/FM index than AGA infants (P<0.001). At 1 month corrected age the LM/FM index and percent fat mass between the groups became similar. Lower lean mass persisted up to 3 months in the SGA group [4004 g (3256–4595) vs. 4432 g (3190–6246), P<0.001]. During the first month corrected age, the weight SDS gain was higher in SGA preterm infants when compared to AGA preterm infants. However, the SGA preterm infants remained lighter, shorter and with smaller head circumferences than the AGA preterm infants until 3 months of corrected age. Conclusions: The greater lean tissue deficits and an earlier “catch-up” in fat in the SGA group can reflect growth patterns variability since the early life.

Energy expenditure, growth, and nutritional therapy in appropriate and small for gestational age preterm infants

OBJECTIVE To evaluate the resting energy expenditure, growth, and quantity of energy and macronutrients intake in a group of preterm newborns. METHODS The cohort study was performed with appropriate and small for gestational age preterm infants (birth weight lower than 1500g or gestational age<32 weeks). Resting energy expenditure was measured using indirect calorimetry on the 7th, 14th, 21st, and 28th days of life, and at discharge. Length, head circumference and body weight were assessed weekly. Nutritional therapy was calculated during the hospital stay and the information for each type of food was recorded in software that calculates the total amount of energy and macronutrients. RESULTS 61 preterm infants were followed; 43 appropriate and 18 small for gestational age infants. There was no statistical difference for resting energy expenditure between the groups, and it increased from the first to the fourth week of life (appropriate: 26.3% and small: 21.8%). Energy intake in the first two weeks of life was well below the energy requirement. CONCLUSION Considering that the results demonstrate high energy expenditure during the first weeks of life, there is an evident need to provide the best quality of nutrition for each child in the first weeks of life so that preterm infants with or without intrauterine growth restriction can achieve their maximum potential for growth and development.