The effect of nitroglycerin and nitroprusside on intramural carbon dioxide tension during acute experimental myocardial ischemia in dogs.

摘要: There is continuing controversy over the effects of nitroglycerin and nitroprusside on myocardial ischemia. In 36 open-chest, anesthetized dogs with normal left ventricular filling pressures, intramural carbon dioxide tension (PmCO2) was measured directly a mass spectrometer during repeated 10-minute coronary artery occlusions separated by 45-minute periods reflow. Simultaneously, regional blood flow (RMBF) in ischemic area quantified microsphere technique. all increase PmCO2 from before to 10 minutes after first occlusion (delta PmCO2) exceeded that subsequent occlusions. those not receiving an intervention (controls), delta third similar second occlusion. When administered occlusion, it caused significantly smaller elevation than which occurred control transmural RMBF region altered. contrast, sodium sufficient reduce mean systemic arterial pressure same extent as no change significant decrease region. Thus, dog reduces tension, but given produce hemodynamic alterations exerts effect PCO2.