VENOUS RESPONSE AFTER LIDOCAINE ADMINISTRATION IN ARM VEINS

We previously reported that cubital venous pressure (Pv) tended to inc rease initially, but this was followed by a drop in a dose-dependent r esponse after intravenous lidocaine administration in subjects with va rious diseases. In this study we examined whether Pv responses after s mall-dose intravenous Lidocaine administrations are related to the sti mulating effect of lidocaine on vascular smooth muscle (VSM). In 5 sub jects free of cardiovascular disease, Pv increased slightly with decre ased pulsations after a 10 mg dose (p<0.01) with no change in central venous pressure. In the cinephlebographic test performed on 2 healthy volunteers, Pv increased during recovery from proximal venoconstrictio n caused by an injection of contrast medium mixed with 10 mg lidocaine . In 9 subjects with cardiovascular disease, Delta Pv spread in the sa me directions (+ or -) after 5 and 10 mg drug administrations. In 6 of those tested with both drug doses, Delta Pv had positive means and no significant difference was observed. Thus, Pv responses after small-d ose lidocaine administrations are consistent with neither the stimulat ing effect of Lidocaine nor with a dose-dependent response. They could be attributed to the spasmolytic effect of lidocaine on the basal ton e of VSM, which could be modulated by disease conditions.