Faculdade de Medicina da, Universidade de São Paulo - FMUSP, São Paulo, Brazil.
Universidade Ibirapuera - UNIB, São Paulo, Brazil.
Eur J Pediatr. 2024 Nov;183(11):4799-4806. doi: 10.1007/s00431-024-05751-9. Epub 2024 Sep 5.
To stratify groups of infants by gestational age and identify the lower limit of normal (LLN) of the cross-sectional area of peripheral muscles as well as diaphragmatic excursion and thickness and parasternal activation during spontaneous respiration in full-term and preterm newborns. A cross-sectional study was conducted at a neonatal unit. Preterm newborns (PTNBs) with gestational age of 28 to 36 weeks and full-term newborns (NBs) with gestational age of 37 to 41 weeks, clinically and hemodynamically stable, breathing ambient air with no signs of respiratory distress were included. NBs on oxygen therapy, those with known genetic syndromes, malformations of the nervous system and those having undergone surgery were excluded. Ultrasound was performed over the rectus femoris, tibialis anterior, and biceps brachii muscles (cross-sectional area) and diaphragm (thickness and excursion). One hundred twenty NBs were stratified based on gestational age (< 30 weeks [n = 25]; 31 to 35 weeks [n = 51]; 37 to 41 weeks [n = 44]). Significant differences were found in the cross-sectional area of the rectus femoris muscles and thigh circumference of NBs > 37 weeks compared to the other 2 groups (p < 0.05). Differences were found in diaphragm thickness and excursion between the groups with gestational age > 37 weeks and < 30 weeks. Greater activation of the parasternal muscles was found in the PTNBs. With regard to LLN, significant differences were found between the groups with gestational age > 37 weeks and < 30 weeks for all variables analyzed and between the group with gestational age > 37 weeks and other 2 groups for the cross-sectional area of the rectus femoris, diaphragmatic excursion, and diaphragm contraction velocity. Differences were found among the groups in the size of peripheral muscles as well as diaphragm thickness and excursion. Moreover, greater activation of the parasternal muscle was found in NBs with gestational age < 30 weeks. This study establishes normal values of ultrasound measures for full-term and preterm newborns.
通过超声评估，对胎龄分组并确定正常下限（LLN），旨在明确足月及早产儿自主呼吸时外周肌肉（股直肌、胫骨前肌、肱二头肌）的横截面积、膈肌活动度和厚度以及胸旁肌激活情况。本研究为横断面研究，在新生儿病房进行。纳入标准：胎龄 28-36 周的早产儿（PTNB）和胎龄 37-41 周的足月新生儿（NB），临床及血流动力学稳定，自主呼吸室内空气，无呼吸窘迫征象。排除标准：接受氧疗、已知有遗传综合征、神经系统畸形或接受过手术的 NB。超声检查股直肌、胫骨前肌和肱二头肌（横截面积）及膈肌（厚度和活动度）。120 例 NB 按胎龄分层（<30 周[n=25]；31-35 周[n=51]；37-41 周[n=44]）。结果：NB 中>37 周组股直肌横截面积和大腿周径与其他 2 组相比有显著差异（p<0.05）。>37 周组和<30 周组间膈肌厚度和活动度有差异。PTNB 组胸旁肌激活程度更高。LLN 方面，>37 周组和<30 周组间所有变量及>37 周组和其他 2 组间股直肌横截面积、膈肌活动度和膈肌收缩速度均有显著差异。各组间外周肌肉大小以及膈肌厚度和活动度有差异。<30 周组 NB 胸旁肌激活程度更高。本研究建立了足月和早产儿超声测量的正常值。
