ABSTRACT
Thoracic anesthesia offers particular challenge. Thoracic patients frequently have a painful wound after surgery. So analgesia after thoracic surgery is of particular significance. In the present study we assessed the efficacy of thoracic paravertebral and epidural blockade on post thoracotomy pain and pulmonary function. Thirty adult ASA I-III patients undergoing elective thoracic surgery were enrolled in this study. they were randomly divided into two groups: paravertebral and epidural group [15 patients each]. Both percutaneous paravertebral and epidural catheters were placed preoperatively. Before chest closure each patient received a bolus dose of bupivacaine [0.25 %] according to its height. This was followed by postoperative bupivacaine infusion [0.25 %] 0.1 ml kg-1h -1 in both groups. Also patients were encouraged to take supplementary doses of morphine from a patient controlled analgesia [PCA]. Subjective pain relief was assessed on a linear visual analogue scale and pulmonary function was measured by spirometry. Stress responses to noxious stimuli was assessed by plasma levels of cortisol and glucose. Respiratory variables were recorded throughout the study period. Also sensory level of analgesia and performance status were assessed in the two groups. Although we found significantly lower visual analogue pain scores at rest and on maximal coughing in the paravertebral compared to the epidural group, no significant difference in patient controlled morphine requirements was noted between the two groups. Pulmonary function [FVC, FEV1 and PEFR] was significantly better in the paravertebral group. Meanwhile no significant difference in respiratory variables was recorded between the two groups. Paravertebral block produced significantly diminished stress responses to noxious stimuli as manifested by less increase in plasma cortisol level than in epidural block. Sensory levels of analgesia and performance status was similar in both groups. Side effects as hypotension, urine retention, nausea and difficulty in breathing were troublesome in the epidural group. While nausea and difficulty in breathing were less in paravertebral group. Like epidural analgesia, paravertebral block deserves to be considered for post thoracotomy pain relief