RESUMO
OBJECTIVE: To evaluate the effect of prone vs supine position on the oxygenation instability among very low birth weight (VLBW) infants receiving noninvasive respiratory support, as assessed by the average oxygen saturation (SpO2) histograms. STUDY DESIGN: Sixty-nine histograms from 23 VLBW infants were studied prospectively. Each infant was studied during 3 consecutive 3-hour periods of alternating positions; 12 infants started the study while prone and 11 infants started supine, by random order. Histogram classification system was used to quantify oxygenation stability and time spent in different SpO2 ranges. RESULTS: The fraction of inspired oxygen values were similar in both positions. Unstable histograms were more common in supine vs prone position (20/34 [59%] vs 10/35 [29%]; P = .02, respectively). Analyzing oxygenation stability as per position change revealed that a change from prone to supine increased oxygenation instability, and supine to prone decreased instability (P = .02). In the supine vs prone position, percent of time spent in SpO2 ≤80% and <90% was higher (5.0 ± 4.2 vs 2.4 ± 3.4 [P < .001] and 24.1 ± 13.7 vs 13.2 ± 10.0 [P < .001], respectively), and percent of time in SpO2 >94% was lower (39.7 ± 26.0 vs 52.4 ± 23.4 [P = .04]). CONCLUSIONS: Prone positioning decreased oxygenation instability and resulted in higher oxygenation among VLBW premature infants on noninvasive respiratory support. SpO2 histograms allow easy bedside assessment of oxygenation instability, and quantification of the time spent at different SpO2 ranges.
Assuntos
Apneia/terapia , Posicionamento do Paciente , Decúbito Ventral , Respiração Artificial , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Decúbito Dorsal , Estudos Cross-Over , Feminino , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Masculino , Saturação de Oxigênio/fisiologia , Estudos ProspectivosRESUMO
OBJECTIVE: To determine the relationship between left ventricular cardiac output (LVCO), superior vena cava (SVC) flow, and brain injury during whole-body therapeutic hypothermia. STUDY DESIGN: Sixteen newborns with moderate or severe hypoxic-ischemic encephalopathy were studied using echocardiography during and immediately after therapeutic hypothermia. Measures were also compared with 12 healthy newborns of similar postnatal age. Newborns undergoing therapeutic hypothermia also had cerebral magnetic resonance imaging as part of routine clinical care on postnatal day 3-4. RESULTS: LVCO was markedly reduced (mean ± SD 126 ± 38 mL/kg/min) during therapeutic hypothermia, whereas SVC flow was maintained within expected normal values (88 ± 27 mL/kg/min) such that SVC flow represented 70% of the LVCO. The reduction in LVCO during therapeutic hypothermia was mainly accounted by a reduction in heart rate (99 ± 13 vs 123 ± 17 beats/min; P < .001) compared with immediately postwarming in the context of myocardial dysfunction. Neonates with brain injury on magnetic resonance imaging had higher SVC flow prerewarming, compared with newborns without brain injury (P = .013). CONCLUSION: Newborns with perinatal hypoxic-ischemic encephalopathy showed a preferential systemic-to-cerebral redistribution of cardiac blood flow during whole-body therapeutic hypothermia, which may reflect a lack of cerebral vascular adaptation in newborns with more severe brain injury.
Assuntos
Débito Cardíaco , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/terapia , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/etiologia , Lesões Encefálicas/fisiopatologia , Estudos de Casos e Controles , Feminino , Frequência Cardíaca , Humanos , Hipotermia Induzida/métodos , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Hipóxia-Isquemia Encefálica/fisiopatologia , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/diagnóstico por imagem , Doenças do Prematuro/fisiopatologia , Doenças do Prematuro/terapia , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Ultrassonografia Doppler de PulsoRESUMO
OBJECTIVE: To assess the safety and prebiotic effects of lactulose in preterm infants. STUDY DESIGN: This was a prospective, double-blinded, placebo-controlled, single-center study in 23- to 34-weeks premature infants. The study group received 1% lactulose, and control infants received 1% dextrose in all feeds (human milk or formula). RESULTS: Twenty-eight infants participated (15 lactulose, 13 placebo). Small doses of lactulose appeared to be safe and did not cause diarrhea. Premature infants on lactulose had more Lactobacilli-positive stool cultures that appeared earlier with larger number of colonies. The lactulose group tended to have less intolerance to enteral feedings, to reach full oral feeds earlier, and to be discharged home earlier. They also tended to have fewer episodes of late-onset sepsis, lower Bell stage necrotizing enterocolitis, and their nutritional laboratory indices were better, especially calcium and total protein. CONCLUSIONS: This pilot study supports the safety of supplementing preterm infants' feeds with low doses of lactulose. It also demonstrated trends that may suggest positive prebiotic effects.