Patients will be randomised into two groups as Group E (those who received general anesthesia after the erector spina plan block) and Group T (those who received general anesthesia after thoracic epidural block).~After the block skin conductivity (galvanic skin response - GSR), body temperature changes, sympathetic and sensory block levels, peri-operative hemodynamic data, postoperative pain scores and analgesic consumption will be recorded.
The aim of this randomised controlled and double-blind study, is to compare the effects of erector spinae plane (ESP) and thoracic epidural (TEA) blocks on peri-operative hemodynamics and analgesia in patients undergoing unilateral mastectomies due to malignancy.