[Hemodynamics in transurethral operations under peridural anesthesia]

Three types of cardiovascular system response were revealed in course of transurethral surgery. In the first 10-20 min after peridural anesthesia there was a decrease in total peripheral vascular resistance in all patients. This provided a positive effect in 84% of them as evidenced by normalized blood pressure, heart rate and cardiac output. In 8% of the operated on, lower total peripheral vascular resistance caused dangerous hypotension due to their weak compensatory mechanisms. 8% had a two-phase blood pressure decrease: firstly its decrease to subnormal levels was associated with lower total peripheral vascular resistance, but a repeated decrease (30-40 min later) in blood pressure to a critical level was initiated by a reduction in cardiac output and depletion of compensatory mechanisms, perhaps, due to a surgical hemorrhage. The both types of hemodynamic destabilization were easily corrected by an alpha-adrenomimetic drug (mezaton) infusions and graded intravenous administration. In case of a proper hemodynamic correction, the peridural anesthesia secured an optimal regime for the function of cardiovascular, respiratory and central nervous systems.