NEUROCOMPORTAMENTO DE BEBÊS NASCIDOS PRÉ-TERMO, PEQUENOS E ADEQUADOS PARA A IDADE GESTACIONAL

Relationship between Maternal Stress and Neurobehavioral Indicators of Preterm Infants in the Neonatal Intensive Care Unit

BACKGROUND

Preterm birth and prolonged neonatal hospitalization are potential sources of stress for mothers of preterm and low birth weight infants.

AIM

To evaluate maternal stress and its association with neurobehavioral indicators of preterm infants during hospitalization in the neonatal intensive care unit.

METHODS

A cross-sectional study was conducted in a neonatal intensive care unit of a hospital in Goiânia, Brazil. The study included preterm and low birth weight infants of both genders and their mothers. The Parental Stressor Scale: Neonatal Intensive Care Unit and the Neurobehavioral Assessment of the Preterm Infant were respectively applied to mothers and infants in the neonatal intensive care unit.

RESULTS

The study involved 165 premature infants and their mothers. The mean age of the mothers was 26.3 years and most had a high school education level (57.6%). Mothers perceived the experience of having an infant in the neonatal intensive care unit as moderately stressful (2.96 ± 0.81). The parental role alteration (4.11 ± 1.03) and sights and sounds (2.15 ± 0.90) subscales exhibited the highest and lowest stress levels, respectively. Significant correlations (rho < -0.3; p < 0.05) were found between maternal stress and neurobehavioral indicators of infants. In the multivariate analysis, low leg tone was a predictor of higher maternal stress. Low tone and limited arm movement were predictors of higher maternal stress in the maternal role item.

CONCLUSIONS

The experience of having a preterm infant hospitalized was considered moderately stressful for mothers. Maternal stress levels were significantly correlated with low scores on neonatal neurobehavioral indicators.

Neurobehavioral signals in preterm infants in body weight check: a quasi-experimental study

OBJECTIVE

to describe and compare the frequency of neurobehavioral signs in preterm infants in traditional and humanized body weight check.

METHODS

a quantitative, quasi-experimental, cross-over study, carried out in a Neonatal Unit at a university hospital with a sample of 30 preterm newborns, randomly assigned and allocated in control group (traditional) and intervention group (humanized), with collection of general data, vital signs before and after procedures and footage.

RESULTS

there was a higher frequency of approach signs in humanized weight check compared to traditional check. Moreover, withdrawal signs were more frequent in traditional weight check compared to humanized check.

CONCLUSION

in this regard, humanized body weight check provided greater benefits to preterm infants, making it necessary to foster discussions about humanization of care, so that this practice can be performed routinely in health units.

Sinais neurocomportamentais em prematuros na verificação do peso corporal: estudo quase-experimental

RESUMO Objetivos: descrever e comparar a frequência dos sinais neurocomportamentais em prematuros na verificação do peso corporal de forma tradicional e humanizada. Método: estudo quantitativo, quase-experimental, tipo cross-over, realizado em uma Unidade Neonatal de um hospital universitário com amostra de 30 recém-nascidos prematuros, randomicamente assinalados e alocados no grupo controle (tradicional) e no grupo intervenção (humanizada), com a coleta de dados gerais, sinais vitais antes e depois dos procedimentos e filmagem. Resultados: observou-se uma frequência maior dos sinais de aproximação na verificação do peso de forma humanizada em relação à tradicional. Além disso, os sinais de retraimento se mostraram mais frequentes na verificação do peso de forma tradicional em comparação à humanizada. Conclusão: desse modo, a verificação do peso corporal de forma humanizada proporcionou maiores benefícios aos prematuros, tornando-se necessário estimular discussões sobre a humanização da assistência, para que esta prática possa ser realizada de forma rotineira nas unidades de saúde.

Quantitative assessment of cerebral metabolism and hemodynamics in small-for-gestational-age (SGA) newborns

Background

Small-for-gestational-age (SGA) newborns represent approximately 10% of births worldwide and 45% of births in some countries. It has been suggested that SGA might cause learning difficulties and behavioral abnormalities in childhood, yet the neurobiological basis for this is poorly understood. In this study, we employed several advanced imaging techniques-including T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI), and phase-contrast (PC) MRI-to quantify oxygen extraction fraction (OEF), global cerebral blood flow (CBF), and cerebral metabolic rate of oxygen (CMRO₂) to elucidate pathophysiological vulnerabilities of SGA neonates.

Methods

A total of 41 newborns were enrolled in this study, consisting of 29 SGA and 12 appropriate-for-gestational-age (AGA) neonates. The SGA group was further divided into subgroups with and without abnormalities on structural MRI, denoted as SGA-a (N=17) and SGA-n (N=12). TRUST and PC MRI were performed to determine OEF, CBF, and CMRO₂. Linear regression analyses were performed to examine physiological parameters' dependence on scan age, gender, and group. Similar analyses were conducted for birth weight and brain volume. Receiver operating characteristic (ROC) curves were used to test physiological parameters' ability to different diagnostic groups.

Results

Regression analysis revealed that CMRO₂ was significantly lower (P=0.04) in the SGA group relative to the AGA group. When further stratifying the SGA participants into SGA-a and SGA-n subgroups, the SGA-a subgroup was found to have the most pronounced physiological deficits, with a lower CMRO₂ (P=0.004) and lower CBF (P=0.007) than those in the AGA group. Conversely, CMRO₂ (P=0.40) and CBF (P=0.90) in the SGA-n subgroup were not different from those of the AGA group. Accordingly, CBF in the SGA-a group was significantly lower (P=0.01) than that of the SGA-n group and CMRO2 also showed a difference (P=0.09). Additionally, CMRO₂ (P=0.002) and CBF (P=0.04) showed an age-related increase during this early developmental period. In analyzing the SGA-a subgroup relative to the remaining neonates, the area under curve (AUC) values were 0.6, 0.6, 0.7, 0.8, and 0.5 for birth weight, OEF, CMRO₂, CBF, and brain volume, respectively. In analyzing the SGA-a subgroup relative to the SGA-n subgroup, AUC values were 0.5, 0.6, 0.7, 0.8, and 0.5 for birth weight, OEF, CMRO₂, CBF, and brain volume.

Conclusions

Structural damage in SGA-a neonates is associated with cerebral hemodynamic and metabolic deficits. SGA neonates with normal CBF and CMRO₂reveal minimal structural abnormalities. Physiological imaging may help identify SGA patients at high risk of developing irreversible brain damage.

The association between restricted intra-uterine growth and inadequate postnatal nutrition in very-low-birth-weight infants and their neurodevelopmental outcomes: a 50-month follow-up study

Inadequate nutrition during a critical period of development - as is the case during gestation and the first days of life, especially in very-low-birth-weight (VLBW) infants, can impact on neurodevelopment and favour co-morbidities. In this study, we evaluate how neurodevelopment may be affected by intra-uterine growth (IUGR) restriction and by an inadequate intake of nutritional energy during the early neonatal period. A longitudinal cohort study was conducted to analyse the nutritional contributions received during the first week of life, among a population of 396 VLBW infants. Motor, cognitive, sensory and behavioural development was assessed at 14, 25, 33 and 50 months. The association between IUGR, postnatal energy restriction and neurodevelopment was examined using multivariate logistic regression techniques. Mild cognitive delay was observed in 35·6 % of neonates with IUGR and in 24 % of those with appropriate birth weight. IUGR is associated with behavioural disorder (OR 2·60; 95 % CI 1·25, 5·40) and delayed cognitive development (OR 2·64; 95 % CI 1·34, 5·20). Energy restriction during the first week of life is associated with visual deficiency (OR 2·96; 95 % CI 1·26, 6·84) and cerebral palsy (OR 3·05; CI 95 % 1·00, 9·54). In VLBW infants, IUGR is associated with behavioural disorder, while postnatal energy restriction is significantly associated with motor disorder, infantile cerebral palsy and sensory disorder.

Neurophysiologic Profiling of At-Risk Low and Very Low Birth-Weight Infants Using Magnetic Resonance Imaging

Low birth-weight (LBW) and very low birth-weight (VLBW) newborns have increased risks of brain injuries, growth failure, motor difficulties, developmental coordination disorders or delay, and adult-onset vascular diseases. However, relatively little is known of the neurobiologic underpinnings. To clarify the pathophysiologic vulnerabilities of such neonates, we applied several advanced techniques for assessing brain physiology, namely T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI) and phase-contrast (PC) MRI. This enabled quantification of oxygen extraction fraction (OEF), global cerebral blood flow (CBF), and cerebral metabolic rate of oxygen (CMRO₂). A total of 50 neonates (LBW-VLBW, 41; term controls, 9) participated in this study. LBW-VLBW neonates were further stratified as those with (LBW-VLBW-a, 24) and without (LBW-VLBW-n, 17) structural MRI (sMRI) abnormalities. TRUST and PC MRI studies were undertaken to determine OEF, CBF, and CMRO₂. Ultimately, CMRO₂ proved significantly lower (p = 0.01) in LBW-VLBW (vs term) neonates, both LBW-VLBW-a and LBW-VLBW-n subsets showing significantly greater physiologic deficits than term controls (p = 0.03 and p = 0.04, respectively). CMRO₂ and CBF in LBW-VLBW-a and LBW-VLBW-n subsets did not differ significantly (p > 0.05), although OEF showed a tendency to diverge (p = 0.15). However, OEF values in the LBW-VLBW-n subset differed significantly from those of term controls (p = 0.02). Compared with brain volume or body weight, these physiologic parameters yield higher area-under-the-curve (AUC) values for distinguishing neonates of the LBW-VLBW-a subset. The latter displayed distinct cerebral metabolic and hemodynamic, whereas changes were marginal in the LBW-VLBW-n subset (i.e., higher OEF and lower CBF and CMRO₂) by comparison. Physiologic imaging may therefore be useful in identifying LBW-VLBW newborns at high risk of irreversible brain damage.