[Effects of a thoracic paravertebral block on postoperative analgesia in patients undergoing modified radical mastectomy].

OBJECTIVES Following mastectomy, 50% of patients have chronic postoperative pain. Studies have shown that a paravertebral block is an effective method of analgesia as well as anaesthesia. The aim of this study is to compare postoperative pain values and opioid consumption after a single dose of 150 mg levobupivacaine with a thoracic paravertebral block in patients undergoing mastectomy. METHODS Enrolled in the study were forty patients, aged 20 to 65, diagnosed with breast cancer, and undergoing modified radical mastectomy and axillary dissection. Patients were randomized into two groups, as control group (group K, n=20) and thoracic paravertebral group (Group T, n=20). Postoperative pain values were recorded at 0, 1st, 6th, 12th and 24th hour at rest, using a 0-10 mm Visual Analogue Scale (VAS). Additional quantities of postoperative tramadol (1.5 mg/kg, iv infusion) were recorded. RESULTS Postoperatively, at 0, 1st, 6th, 12th and 24th hour, patients in the control group had significantly higher VAS values than the group treated with a thoracic paravertebral block (p<0.01). Compared to VAS scores at postoperative 0 h, there was a statistically significant decrease in VAS scores at 1st, 6th, 12th and 24th hour in both groups (p<0.01). Additional use of tramadol was significantly lower in group T (p<0.01). CONCLUSION A paravertebral block with a single dose of 150 mg levobupivacaine before general anaesthesia in patients undergoing modified radical mastectomy and axillary lymph node dissection decreases postoperative pain values and the need for analgesics during the postoperative 24 hours.