RESUMO
OBJECTIVE: To evaluate peripheral regional oxygen saturation (rpSO2) and cerebral regional oxygen saturation (rcSO2) during the immediate postnatal transition in late preterm infants with and without the need for respiratory support. STUDY DESIGN: This was a prospective observational study using near-infrared spectroscopy to evaluate changes in rpSO2 and rcSO2. These variables were measured during the first 15 minutes of life after elective cesarean delivery. Peripheral oxygen saturation (SpO2) and heart rate were measured continuously by pulse oximetry, and cerebral fractional tissue oxygen extraction (cFTOE) was calculated. Two groups were compared based on their need for respiratory support: a respiratory support group and a normal transition group. Positive-pressure ventilation was delivered with a T-piece resuscitator, and oxygen was adjusted based on SpO2 values. A Florian respiratory function monitor was used to record the ventilation variables. RESULTS: There were 21 infants in the normal transition group and 21 infants in the respiratory support group. Changes in heart rate over time were similar in the 2 groups. SpO2, rcSO2, and rpSO2 values were consistently higher in the normal transition group. In the respiratory support group, cFTOE values remained significantly elevated for a longer period. CONCLUSION: This systematic analysis of rpSO2, rcSO2, and cFTOE in late preterm infants found significantly lower oxygen saturation values in infants who received respiratory support compared with a normal transition group. We hypothesize that the elevated cFTOE values in the respiratory support group represent compensation for lower oxygen delivery.
Assuntos
Encéfalo/metabolismo , Recém-Nascido Prematuro/metabolismo , Oxigênio/metabolismo , Feminino , Humanos , Recém-Nascido , Masculino , Estudos Prospectivos , Fatores de TempoRESUMO
OBJECTIVE: To evaluate differences in regional oxygen saturation of the brains of term infants of vaginal or cesarean deliveries. STUDY DESIGN: Vaginal delivery (n = 63) and elective cesarean delivery infants were prospectively evaluated for the first 10 minutes after delivery. Peripheral arterial oxygen saturation (SpO(2)) and heart rate were measured on the right hand using pulsoximetry with near infrared spectroscopy. Regional oxygen saturation of the brain (rSO(2)brain) was measured. Fractional tissue oxygen extraction was calculated for each minute. RESULTS: From 4 to 8 minutes, SpO(2) values for cesarean delivery infants were significantly lower than for vaginally delivered infants. Heart rate of the cesarean delivery infants was significantly lower throughout the whole observation period. There was no difference between groups in rSO(2)brain. Fractional tissue oxygen extraction only differed at minute 10. CONCLUSIONS: Although SpO(2) and heart rate were significantly lower in cesarean-delivered infants, there were no differences in rSO(2)brain with respect to mode of delivery.
Assuntos
Encéfalo/metabolismo , Cesárea , Parto Obstétrico , Oxigênio/metabolismo , Feminino , Frequência Cardíaca , Humanos , Recém-Nascido , Masculino , Oximetria , Gravidez , Estudos Prospectivos , Espectroscopia de Luz Próxima ao Infravermelho , Nascimento a Termo , Fatores de TempoRESUMO
OBJECTIVE: To evaluate regional tissue oxygenation of the brain and preductal and postductal peripheral (muscle) tissue during immediate transition after birth, and to correlate with peripheral preductal and postductal arterial oxygen saturation. STUDY DESIGN: We conducted a prospective observational study. With near-infrared spectroscopy (NIRS), changes in regional oxygen saturation of the brain (rSO2brain), peripheral preductal tissue (rSO2pre), and peripheral postductal tissue (rSO2post) were measured during the first 10 minutes of life in 59 healthy term infants after elective caesarean delivery. Fractional tissue oxygen extraction was calculated for all 3 regions. RESULTS: Mean rSO2brain increased rapidly from 44% (3 minutes) to 76% (7 minutes); thereafter no significant change occurred. Mean rSO2pre and rSO2post increased constantly from minute 3 to minute 10, from 36%(pre)/27%(post) to 66%(pre)/58%(post). Fractional tissue oxygen extraction decreased in all 3 regions during the first minutes of life. Fractional tissue oxygen extraction of the brain did not change significantly after 5 minutes, and preductal and postductal fractional tissue oxygen extraction did not change significantly after 8 minutes. CONCLUSIONS: During transition, the brain had the highest saturation levels, indicating a preference of oxygen delivery to the brain. Fractional tissue oxygen extraction of the brain reached a plateau earlier compared with peripheral tissue.