Lower limit of normal of cross-sectional area of peripheral muscles and diaphragm measurements performed with ultrasound in full-term and preterm infants

• Published in: European journal of pediatrics 2024-11, Vol.183 (11), p.4799-4806
• Main Authors: Martins, Maria Fernanda, de Santa Maria, Natasha Nicholson, dos Santos Camargo, Carolina Cristina, Anjos, Débora Nunes Prata, de Carvalho, Etiene Farah Teixeira, de Freitas Dantas Gomes, Evelim Leal
• Format: Article
• Language: English
• Subjects: Age; Cross-Sectional Studies; Diaphragm; Diaphragm - anatomy & histology; Diaphragm - diagnostic imaging; Female; Gestational Age; Humans; Infant, Newborn; Infant, Premature; Infants; Male; Medicine; Medicine & Public Health; Muscle contraction; Muscle, Skeletal - anatomy & histology; Muscle, Skeletal - diagnostic imaging; Neonates; Nervous system; Newborn babies; Pediatrics; Reference Values; Respiration; Skeletal muscle; Ultrasonic imaging; Ultrasonography - methods; Ultrasound
• ISSN: 1432-1076; 0340-6199; 1432-1076
• DOI: 10.1007/s00431-024-05751-9

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 6/7  weeks and full-term newborns (NBs) with gestational age of 37 to 41 6/7  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 ( 37 weeks compared to the other 2 groups ( p   37 weeks and  37 weeks and  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