Hemodynamic Effects of Pulmonary Arterial Infusion of Vasodilators in Newborn Lambs
| Autor: | Willa H. Drummond, Abraham M. Rudolph, Marjorie E Tripp, Michael A. Heymann |
|---|---|
| Rok vydání: | 1980 |
| Předmět: |
Prostaglandins E
Synthetic Pulmonary Circulation Cardiac output Vasodilator Agents Blood Pressure Vasodilation Pulmonary Artery Hypoxemia medicine Animals Infusions Intra-Arterial Hypoxia Sheep business.industry Hemodynamics Oxygenation medicine.disease Pulmonary hypertension Acetylcholine medicine.anatomical_structure Blood pressure Animals Newborn Regional Blood Flow Anesthesia Pediatrics Perinatology and Child Health Breathing Vascular resistance Tolazoline Vascular Resistance medicine.symptom business |
| Zdroj: | Pediatric Research. 14:1311-1315 |
| ISSN: | 1530-0447 0031-3998 |
| DOI: | 10.1203/00006450-198012000-00007 |
| Popis: | Summary: Pulmonary arterial infusion of prostaglandin E1 (mean dose, 1 μg/kg/min) in term neonatal lambs ventilated with room air resulted in a slight fall hi pulmonary arterial pressure (P ≤0.05). Infusion during ventilation with low oxygen mixtures resulted in a parallel fall in pulmonary and arterial pressures and resistances. Intrapulmonary infusion of acetylcholine (mean dose, 3.9 μg/kg/min) in lambs during ventilation with room air caused a slight fall in mean systemic arterial pressure and systemic vascular resistance. When repeated with low oxygen ventilation, infusion of acetylcholine caused a parallel fall in both pulmonary and systemic arterial pressures and resistances. Infusion of tolazoline at a mean dose of 0.21 mg/kg/min did not change pulmonary or systemic arterial pressures or resistances when the lambs were ventilated with room air or with hypoxic gas mixtures although individual animals experienced marked falls in systemic arterial pressure. Pulmonary arterial infusion of each of the three vasodilators during hypoxic ventilation resulted hi potentially adverse hemodynamic effects. This occurred despite prior ductal ligation, implying that doses effective for pulmonary vasodilatation may exceed doses without systemic effects particularly hi the acute hypoxic state. Speculation: Vasodilators specific for pulmonary vascular smooth muscle have not been developed. Nonspecific vasodilators cause relaxation of pulmonary and systemic-vascular smooth muscle which is most marked during hypoxemia. Increased pulmonary blood flow will result from vasodilatation only if the ratio of pulmonary to systemic vascular resistance decreases or if cardiac output rises. Parallel changes in pulmonary and systemic resistance with vasodilators during hypoxic pulmonary hypertension with right to left shunting may prevent clinically useful improvement in oxygenation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|