title: Effect of CO2 on myocardial contractility and aortic input impedance during anaesthesia.
abstract: The haemodynamic responses to hypocapnia and hypercapnia have been studied in the dog during intermittent positive pressure ventilation under halothane anaesthesia (1% halothane in oxygen) and under nitrous oxide anaesthesia (30% oxygen in nitrous oxide). In the absence of significant variations of either myocardial contractility or left ventricular end-diastolic pressure, the changes of stroke volume and cardiac output (diminution because of hypocapnia, augmentation because of hypercapnia) were determined by alterations of systemic vascular resistance (augmentation because of hypocapnia, diminution because of hypercapnia).
mesh_terms: D000769:Anesthesia, Inhalation; D000818:Animals; D001013:Aorta, Thoracic; D001783:Blood Flow Velocity; D001794:Blood Pressure; D002245:Carbon Dioxide / Q000097:blood*; D002302:Cardiac Output; D004285:Dogs; D006221:Halothane; D006321:Heart / Q000502:physiology*; D006339:Heart Rate; D006352:Heart Ventricles; D007384:Intermittent Positive-Pressure Breathing; D009200:Myocardial Contraction; D009609:Nitrous Oxide; D014655:Vascular Resistance
chemical_list: D002245:Carbon Dioxide; D009609:Nitrous Oxide; D006221:Halothane