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431.
Amer Ammari Karl F. Schulze Kiyoko Ohira-Kist Sudha Kashyap William P. Fifer Michael M. Myers Rakesh Sahni 《Early human development》2009,85(8):497-501
Background
Low birth weight (LBW) infants sleeping prone are known to exhibit many physiological differences from those sleeping supine, including lower energy expenditure (heat production) and higher surface temperature. This apparent increase in heat storage suggests that heat loss may be inhibited in the prone position which, in turn, might influence cardiorespiratory activity.Aims
To determine the effects of body position (prone vs. supine) on absolute surface temperature profile (heat storage), central-peripheral (C-P) thermal gradients (vasomotor response), cardiorespiratory activity and metabolic gas exchange in growing LBW infants.Methods
Six-hour continuous recordings of absolute surface temperature profiles, cardiorespiratory activity and O2 and CO2 exchange, along with minute-to-minute assessment of behavioral sleep states were performed in 32 healthy growing LBW infants (birth weight 805-1590 g, gestational age 26-35 weeks and postconceptional age at study 33-38 weeks). Each infant was randomly assigned to the prone or supine position for the first 3 h of the study and then reversed for the second 3 h. Surface temperatures were recorded from 4 sites (forehead, flank, forearm and leg) and averaged each minute. Central (forehead and flank)-to-peripheral (forearm and leg) and forehead-to-environment (H-E) thermal gradients were calculated from the surface temperatures. Corresponding sleep states were aligned with minute averages obtained from the temperature and cardiorespiratory measurements. Data were then sorted for prone and supine positions during quiet (QS) and active sleep (AS) and compared using paired t-tests.Results
In the prone position during both AS and QS, infants had higher forehead, flank, forearm and leg surface temperatures, narrower C-P gradients, higher heart rates and respiratory frequency, and lower heart rate and respiratory variability. Despite similar environmental temperatures, the H-E gradient was higher in the prone position. In the prone position infants demonstrated lower O2 consumption and CO2 production and a higher respiratory quotient.Conclusions
Despite thermoregulatory adjustments in cardiorespiratory function, infants sleeping prone have relatively higher body temperature. The cardiorespiratory responses to this modest increase in temperature indicate that thermal and metabolic control of cardiac and respiratory pumps seem to work in opposition. The consequences of any attendant changes in blood gas activity (e.g. hypocapnia and/or increased mixed venous oxygen concentration) due to this override of metabolic control remains speculative. 相似文献432.
Neonatal EEG linked to individual differences in socioemotional outcomes and autism risk in toddlers
Natalie H. Brito Amy J. Elliott Joseph R. Isler Cynthia Rodriguez Christa Friedrich Lauren C. Shuffrey William P. Fifer 《Developmental psychobiology》2019,61(8):1110-1119
Research using electroencephalography (EEG) as a measure of brain function and maturation has demonstrated links between cortical activity and cognitive processes during infancy and early childhood. The current study examines whether neonatal EEG is correlated with later atypical socioemotional behaviors or neurocognitive delays. Parental report developmental assessments were administered to families with children ages 24 to 36 months who had previously participated in a neonatal EEG study (N = 129). Significant associations were found between neonatal EEG (higher frequencies in the frontal polar, temporal, and parietal brain regions) and BITSEA ASD risk scores. Infants with lower EEG power in these brain areas were more likely to have higher risk of socioemotional problems. When examining sex differences, significant links were found for males but not for females. These results demonstrate some promising associations between early neural biomarkers and later risk for atypical behaviors, which may shape early neurobehavioral development and could lead to earlier identification and intervention. 相似文献
433.
434.
Pamela Fifer 《Teaching and Learning in Nursing》2012,7(1):6-9
Nurse educators must explore innovative ways to engage students and stimulate learning. Student response system (SRS) technology is one tool educators can use to increase participation, provide immediate feedback, and encourage critical thinking. This study evaluated perceptions of first-year nursing students using SRS technology. The findings support the use of SRS technology as a positive pedagogical approach to incorporate in teaching associate degree nursing students. 相似文献