Hemodynamic Effects of Norepinephrine in Severe Hypnotic Drug Poisoning With Arterial Hypotension

The hemodynamic response to infusion of norepinephrine (NE) has been measured in 12 patients with severe hypnotic drug poisoning. All patients had a mean arterial blood pressure (B.P.) of 70 mmHg or less initially. As evaluated from central venous pressure no marked hypovolemia was present. Cardiac output (C.O.) was determined by the dye dilution method and right heart catheterization by a “floating” catheter technique. Following infusion of NE the arterial B.P. and C.O. increased. The increase in C.O. resulted from increases in stroke volume and to a less extent also in heart rate (HR). There was no significant change of peripheral vascular resistance index (PVRI), in contrast to the NE effect in cardiogenic, hemorrhagic and septic shock states. The increase in arterial B.P. was accompanied by an increase in HR, which implies a disturbed function of the high pressure baroreceptor system. The rise in B.P. is primarily due to the increase in C.O. No adverse effects were noted during the NE infusion. It is concluded that NE is beneficial in the treatment of severe hypnotic drug poisoning complicated by hypotension.