RESUMO
OBJECTIVE: This study was designed to test the hypothesis that nitric oxide inhalation increases systemic arterial blood oxygen tension of prematurely delivered infants with respiratory distress syndrome. METHODS: Nitric oxide was administered to 23 preterm infants with a diagnosis of respiratory distress syndrome. The infants were randomly assigned to receive either 5 or 20 ppm of nitric oxide and were studied between 24 and 168 hours after delivery. The treatment period for each infant lasted 15 minutes and was preceded by and followed by a 15-minute control period. We evaluated all outcome variables by using two-way repeated measures analysis of variance; p values less than 0.01 were considered significant. RESULTS: Nitric oxide inhalation caused significant increases in the following: arterial blood oxygen tension, directly measured arterial oxyhemoglobin saturation, and transcutaneously measured arterial oxyhemoglobin saturation. No differences between the effects of the two nitric oxide concentrations were detected, nor were residual effects detected 15 minutes after either dose of nitric oxide was discontinued. CONCLUSIONS: Inhalation of both 5 and 20 ppm nitric oxide causes concentration-independent increases in the blood oxygen tensions of preterm infants with respiratory distress syndrome. We speculate that nitric oxide inhalation may be a useful adjunctive therapy for these patients.
Assuntos
Óxido Nítrico/administração & dosagem , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Medicamentos para o Sistema Respiratório/administração & dosagem , Administração por Inalação , Análise de Variância , Terapia Combinada , Relação Dose-Resposta a Droga , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Oxigenoterapia , Estudos Prospectivos , Respiração Artificial , Síndrome do Desconforto Respiratório do Recém-Nascido/sangue , Resultado do TratamentoRESUMO
Two unrelated infants with low Apgar scores, pneumothoraces, and severe pulmonary hypertension were treated with extracorporeal membrane oxygenation while receiving chemical sedation and neuromuscular paralysis. After decannulation from extracorporeal membrane oxygenation, hypotonia and hypoventilation persisted. Neurologic evaluation confirmed that both infants had a congenital myopathy.
Assuntos
Doenças Neuromusculares/congênito , Síndrome da Persistência do Padrão de Circulação Fetal/complicações , Insuficiência Respiratória/etiologia , Oxigenação por Membrana Extracorpórea , Evolução Fatal , Humanos , Recém-Nascido , Masculino , Doenças Neuromusculares/complicações , Síndrome da Persistência do Padrão de Circulação Fetal/terapiaAssuntos
Doenças da Aorta/tratamento farmacológico , Recém-Nascido Prematuro , Terapia Trombolítica , Trombose/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Cateterismo Periférico/efeitos adversos , Humanos , Recém-Nascido , Ativador de Plasminogênio Tecidual/administração & dosagem , Ultrassonografia , Artérias UmbilicaisRESUMO
We evaluated the cardiopulmonary interaction of tolazoline and low-, medium-, and high-dose dopamine infusion (2.7, 27, and 270 micrograms/kg/min) in 11 normal, chronically instrumented, unsedated neonatal lambs. Concomitant tolazoline and dopamine infusions caused tachycardia at all dopamine doses and blocked alpha-adrenergic-mediated increases in systemic resistance and left atrial pressure caused by medium and high doses of dopamine. Moderate doses of dopamine alone increased cardiac output. During simultaneous tolazoline infusion, dopamine increased cardiac output at both moderate and high doses. The effect of dopamine on pulmonary artery pressure was not modified by tolazoline; pulmonary pressure increased similarly with dopamine alone and with dopamine plus tolazoline. Calculated pulmonary vascular resistance rose with dopamine alone, but not with infusion of tolazoline and dopamine, because pulmonary blood flow rose in proportion to pulmonary artery pressure.
Assuntos
Animais Recém-Nascidos/fisiologia , Dopamina/farmacologia , Hemodinâmica/efeitos dos fármacos , Circulação Pulmonar/efeitos dos fármacos , Tolazolina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Ovinos , Resistência Vascular/efeitos dos fármacosRESUMO
We studied the separate and combined effects of hyperventilation and administration of dopamine and tolazoline in five infants with pulmonary hypertension managed with indwelling pulmonary artery catheters. In five infants the right-to-left shunt reversed during ventilator-induced respiratory alkalosis (pH greater than 7.6). Response to drugs was variable and unpredictable. One infant could be oxygenated at normal pH during combined dopamine and tolazoline infusion. Other infants showed no response to drugs, or became worse during infusion. The ratio of pulmonary artery to systemic artery pressure averaged 1.14 with standard therapy, but decreased to 0.98 following respiratory alkalosis alone, to 0.87 following drug infusions, and to 0.70 following the combination of alkalosis and drug infusion. These changes were significant by analysis of variance at P less than 0.02, P less 0.001, and P less than 0.001, respectively. Systemic oxygenation was satisfactory in all cases when the pulmonary to systemic pressure ratio was less than 1.0.