RESUMO
Because premature infants have been shown to be at risk for hypoxia and bradycardia when positioned in standard car seats, this study was done to confirm this finding in a larger sample, to investigate convalescent term infants in the neonatal intensive care unit for respiratory compromise in car seats, and to determine the physiologic mechanism or mechanisms responsible. Extensive multichannel polygraph recordings were obtained and pulmonary function tests were performed on 50 convalescent infants from the neonatal intensive care unit before, during, and after placement in a Cosco-Peterson First Ride car seat. Mean total dynamic compliance, total pulmonary resistance, and work of breathing improved in the car seat. Thirty percent of premature infants experienced hypoxia, bradycardia, or both in a car seat; in this group, tidal volume was lower (p = 0.02). In 11 of 16 infants with abnormal findings, oxygen desaturation was temporally related to episodes of short and mixed apnea. No term convalescent infant experienced respiratory difficulty in a car seat regardless of primary diagnosis. We conclude that premature infants may have respiratory compromise of a multifactorial nature when in car seats. Further development of car seats is necessary if such respiratory problems are to be avoided.
Assuntos
Bradicardia/epidemiologia , Hipóxia/epidemiologia , Equipamentos para Lactente , Doenças do Prematuro/fisiopatologia , Transporte de Pacientes/métodos , Resistência das Vias Respiratórias , Bradicardia/fisiopatologia , Convalescença , Feminino , Humanos , Hipóxia/fisiopatologia , Recém-Nascido , Tempo de Internação , Complacência Pulmonar , Masculino , Monitorização Fisiológica , Testes de Função Respiratória , Volume de Ventilação PulmonarRESUMO
We examined 30 newborn infants for respiratory compromise before, during, and after placement in a recommended car seat restraining device. Twelve infants were premature with a history of apnea, eight were premature without known apnea, and 10 were born at term. Both premature groups had significant decreases in oxygen saturation while in the car seat (P less than 0.01) and more frequent desaturation episodes less than 80% (P less than 0.001). Premature infants with a history of apnea had more bradycardia events (P less than 0.05). No normal term infant had any of these problems. In addition, oxygen saturation trended downward from baseline for all premature infants during the recovery interval (P = 0.07). We conclude that currently available car seats may place premature infants at risk for significant hypoxia and ventilatory compromise.
Assuntos
Hipoventilação/etiologia , Recém-Nascido Prematuro , Equipamentos de Proteção , Apneia/complicações , Automóveis , Peso ao Nascer , Feminino , Frequência Cardíaca , Humanos , Hipóxia/etiologia , Lactente , Recém-Nascido , Masculino , Oxigênio/sangue , RiscoRESUMO
We examined the correlation between the elimination half-life of gentamicin and postnatal or postconceptional age in 104 infants greater than 24 weeks to less than or equal to 48 weeks postconceptional age. A weak correlation was observed between half-life and postnatal age (R = -0.353). A better correlation existed between postconceptional age and half-life (R = -0.572). A plot of the log of the mean half-life against postconceptional age was virtually linear. We conclude that postconceptional age is a major determinant of an infant's ability to excrete gentamicin, and speculate that the relationship between half-life and decreasing postconceptional age is exponential.