【正文】 NITROPRUSSIDE ? Vasodilator that acts directly on arterial and venous vascular smooth muscle. ? Indicated in hypertension and low cardiac output states with increased SVR. ? Also used in postoperative cardiac surgery to decrease afterload on an injured heart. ? Action is immediate。 halflife is short。 titratable action. NITROPRUSSIDE ? Toxicity is with cyanide, one of the metabolites of the breakdown of nipride. ? Severe, unexplained metabolic acidosis might suggest cyanide toxicity. ? Dose starts at mcg/kg/min and titrate to 5 mcg/kg/min to desired effect. May go higher (up to 10 mcg/kg/min) for short periods of time. NITROGLYCERIN ? Direct vasodilator as well, but the major effect is as a venodilator with lesser effect on arterioles. ? Not as effective as nitroprusside in lowering blood pressure. ? Another potential benefit is relaxation of the coronary arteries, thus improving myocardial regional blood flow and myocardial oxygen demand. NITROGLYCERIN ? Used to improve myocardial perfusion following cardiac surgery ? Dose ranges from to 8 mcg/kg/min. Typical dose is 2 mcg/kg/min for 24 to 48 hours postoperatively ? Methemoglobinemia is potential side effect ISOPROTERENOL ? Synthetic catecholamine ? Nonspecific beta agonist with minimal alphaadrenergic effects. ? Causes inotropy, chronotropy, and systemic and pulmonary vasodilatation. ? Indications: bradycardia, decreased cardiac output, bronchospasm (bronchodilator). ? No longer available in some markets ISOPROTERENOL ? Occasionally used to maintain heart rate following heart transplantation. ? Dose starts at mcg/kg/min and is increased to mcg/kg/min for desired effect. INHALED NITRIC OXIDE ? Selective Pulmonary vasodilator ? Dilates only pulmonary capillaries to alveoli participating in gas exchange ? Decreases intrapulmonary shunt and improves V/Q matching ? Rapidly inactivated by Hgb in pulm. cap. so no systemic side effects (eg hypotension) INHALED NITRIC OXIDE ? Potential for use in ARDS and Pulmonary Hypertension ? Currently only approved for use in neonatal Pulmonary Hypertension ? Expensive ? Special monitoring equipment required ? Dose: Concentration of ppm in inhaled gas Additional considerations ? Mechanical ventilation and oxygen therapy (to conserve CO) ? Analgesia, anxiolysis and sedation ? Electrolyte homeostasis esp Ca and Mg ? Nutrition avoid hypoglycemia ? Anemia is an “unconstitutional surcharge” ? Last but not the least: Maintain appropriate intravascular volume Selecting inotropic and vasopressor agents for specific hemodynamic disturbances in children Hemodynamic pattern Normal Deceased Elevated Blood pressure or SVR Septic Shock Stroke index High Stroke Index low to N None or dopamine Dobutamine or dopamine Norepinephrine Dopamine or epinephrine (or dobutamine plus norephinephrine) None Dobutamine plus nitroprusside Cardiogenic shock Dobutamine or amrinone or dopamine Epinephrine or dopamine Myocardial dysfunction Dobutamine or dopamine or amrinone Epinephrine or dopamine (or dobutamine plus norepinephrine) Dobutamine plus nitroprusside CHF Dobutamine or dopamine or amrinone Dobutamine plus nitroprusside Bradycardia None Isoproterenol None DRIP FORMULA: 6 X WT. IN KG X MCG/KG/MIN = mg in 100 ml of D5W/NS ML/HR Also another way to calculate is: ISOPROTERENOL EPINEPHRINE NOREPRINEPHRINE } X BODY WT. IN KG = ____ MG IN 100ML 1 ML/HR WILL DELIVER MCG/KG/MIN DOPAMINE DOBUTAMINE AMRINONE NITROPRUSSIDE } 6 X BODY WT. IN KG = _____ MG IN 100ML 1 ML/HR WILL DELIVER 1 MCG/KG/MIN 分類 ? Inotropes: agents that improve myocardial contractility and enhance stroke volume ? Pressors: agents that increase systemic vascular resistance and increase blood pressure ? Chronotropic: Increase heart rate ? improve relaxation during diastole and decrease EDP in the ventricles 分類 ? 強(qiáng)心 (升壓 ) ? Bosmine ? Levophed ? Dopamine ? Dobutamine ? Primacor ? 降壓 ? NTG ? Nitroglyceride ? Perdipine ? 控制心率 ? Amirodarone ? Isuprel