[Controlled pulmonary arterial hypotension using obsidan and sodium nitroprusside in the early period following closed mitral commissurotomy].

Controlled pulmonary hypotension using sodium nitroprusside in combination with propranolol was employed in 23 patients in the early postoperative period after closed mitral valvulotomy. Pulmonary circulation, gas exchange and some nonrespiratory pulmonary functions have been assessed. It has been shown that increased blood levels of serotonin, histamine, noradrenaline and especially cyclic adenosine monophosphate play an essential role in the pathogenesis of postoperative pulmonary vasoconstriction.