RESUMO
Renal function during indomethacin treatment was studied in 12 premature infants with patent ductus arteriosus. Decreases in urinary flow rate, GFR, and CH2O by 56, 27, and 66%, respectively, occurred during Indo therapy. Urinary excretion rates of ions were also reduced: Na by 70%, Cl by 79%, K by 40%. These changes were accompanied by slight decreases in plasma sodium concentration and osmolality. Except for GFR and urinary Na and osmolality, all these functions returned to pretreatment values one to two weeks after stopping the drug.
Assuntos
Permeabilidade do Canal Arterial/fisiopatologia , Indometacina/farmacologia , Doenças do Prematuro/fisiopatologia , Rim/fisiopatologia , Permeabilidade do Canal Arterial/tratamento farmacológico , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Indometacina/uso terapêutico , Recém-Nascido , Doenças do Prematuro/tratamento farmacológico , Rim/efeitos dos fármacosRESUMO
The pulmonary vascular effects of tolazoline were studied in unsedated newborn lambs during normal oxygenation and hypoxia. Direct and indirect pulmonary vascular responses were analyzed separately. During normal oxygenation, tolazoline (1 mg/kg) given into a branch pulmonary artery increased cardiac output while decreasing systemic and pulmonary resistances. Pulmonary flow distribution did not change, suggesting that the fall in pulmonary resistance was due to an indirect rather than a direct action of the drug. Tolazoline had similar effects on systemic and pulmonary resistances in the hypoxic lamb; however, there was a shift in blood flow toward the injected lung, indicating local pulmonary vasodilation induced by the drug. In either case, tolazoline did not alter the resistance ratio between the injected lung and the systemic circulation. We conclude that tolazoline is a direct pulmonary vasodilator in the hypoxic lamb, but does not appear to lower the pulmonary to systemic resistance ratio.