l-Norepinephrine and the Pulmonary Circulation

Effect of l-norepinephrine on left ventricular diastolic pressures in man

“…These findings accord with observations concerning the action of l-norepinephrine on the lesser circulation as previously reported and show a possible back pressure effect between the left ventricular end-diastolic pressure and the right atrial diastolic pressure (Cudkowicz and O'Neill, 1964). The total mean diastolic pressure elevation across the lesser circulation at the end of the tenth minute of i-norepinephrine infusion is 6-1 mm.…”

“…), and pulmonary wedge (P.C.P.) pressures were observed under similar conditions (Cudkowicz and O'Neill, 1964). With the emergence of a 'square wave' peripheral arterial blood pressure pattern at a mean time of 9-5 minutes of l-norepinephrine infusion, identical 'square wave' patterns emerge throughout the pulmonary circulation.…”

“…4) (Cudkowicz and O'Neill, 1964). The time component seems critical in the conversion of the normal arterial blood pressure response to Valsalva's manceuvre during 1-norepinephrine infusions in man.…”

“…The cardiac output, total pulmonary vascular resistance, oxygen consumption, and minute ventilation did not change. It was then suggested that the 'square wave' response throughout the lesser circulation during l-norepinephrine infusions of not less than 10 minutes is dependent upon a passive elevation in all diastolic pressures of the lesser circulation attending on a similar rise in diastolic pressures of the left ventricle (Cudkowicz and O'Neill, 1964).…”