[Subarachnoidal anesthesia in patients with concomitant diseases of the cardiovascular system]

Age-related changes limit blood circulatory reserves in vital organs, by increasing the risk of ischemic and hypoxic lesions. Patients from a peripheral vascular surgery department form a high cardiac risk group. Subarachnoidal anesthesia is the most optimal anesthetic support (if there are no absolute contraindications) during operations for lower extremity varicose veins. Thirty patients operated on for this condition were examined to solve the problem associated with the effectiveness and safety of this method of anesthesia and to define the pattern of hemodynamic rearrangement more precisely. All the patients had concomitant cardiovascular diseases, which forced them to be referred to as ASA Classes III-IV. The authors monitored basic hemodynamic parameters, such as systolic blood pressure (BP), diastolic BP, mean BP (BP(mean)), heart rate, and cardiac output, by using a noninvasive procedure by means of a computer equipped with a Doppler flowmetric transducer, and ST-segment changes by ECG). The values of total and specific peripheral vascular resistance and cardiac index were estimated by a calculating method. Analysis of hemodynamic changes revealed no significant differences between the groups of elderly and senile patients. On examination, all the patients were divided into 2 groups by the type of circulation: 1) those with eukinetic circulation and 2) those with hypokinetic circulation. Hyperkinetic circulation was not found in the study groups of patients. The patients with cardiac disease were observed to have increased vascular resistance, in those with hypokinetic circulation, this increase being more marked (p < 0.05). In addition, ST-segment had a more stable position in patients with hypokinetic circulation. There was a great scatter in ST-segment changes in patients with eukinetic circulation in the presence of decreased peripheral resistance under preganglionic sympathetic block. With the described changes, noteworthy was the stability of BP(mean) values that did not decreased below the critical ones. This fact permitted the authors to state that the compensatory reserves of the cardiovascular system were preserved under subarachnoidal blockade, which in turn suggests the effectiveness and safety of the used anesthetic procedure.