Der Anaesthesist
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Impaired right ventricular (RV) function may be caused by pulmonary hypertension or myocardial ischemia. It is characterized by a dilation of the RV, which is followed by an increase of wall tension and O2-consumption and a decrease of RV ejection fraction (RV 'dysfunction'). If a drop of arterial pressure occurs this my precipitate RV failure and shock (RV 'insufficiency'). ⋯ Norepinephrine presently is the drug of choice for this purpose. 3) Reduction of RV afterload: Whereas intravenous vasodilators are limited in their efficacy in dilating pulmonary vessels due to systemic side effects, inhaled vasodilators result in selective pulmonary vasodilation and may improve RV function. 4) Increase of RV contractility: In RV failure and shock, norepinephrine and epinephrine are the drugs of choice. Inodilators are well suited for reducing pulmonary vascular resistance due to their positive inotropic and vasodilating effects. Since systemic vasodilation may occur, these drugs must only be used in hemodynamically stable patients.