Thoracic Paravertebral Block as a Component of General Anesthesia in the Surgical Treatment of Unstable Angina Pectoris

Abstract

Objective: to evaluate the efficiency of high thoracic paravertebral block as an anesthetic component in the surgical treatment of unstable angina pectoris. Subjects and methods. Twenty-six patients aged 38 to 67 years who had unstable angina pectoris and who had underwent surgical myocardial revascularization were examined. A study group included 12 patients in whom high thoracic paravertebral block (Th3—Th4—Th5) with 0.75% ropivacaine solution was used as an additional component of general anesthesia. No paravertebral block was conducted in a comparison group (n=14). Randomization was made by the envelop method in a ratio of 2:1. The groups were stratified by age, gender, the class of unstable angina, myocardial contractility, and the type of an operation. Results. Paravertebral block was ascertained to significantly increase the analgesic component of general anesthesia in the surgical treatment of unstable angina. In the study group of patients, there were more steady-state central hemodynamic parameters at surgical stages than in the comparison group, which contributed to a reduction in the number of critical episodes during anesthesia. The level of stress hormones at the surgical stages also indicated effective analgesia when high thoracic paravertebral block was used. Furthermore, the use of this technique of regional anesthesia substantially optimized an early postoperative period — there were fewer needs for opioids. Key words: paravertebral block, regional anesthesia, acute coronary syndrome, surgical myocardial revascularization.