COMPARATIVE-STUDY OF CONTINUOUS EXTRAPLEURAL INTERCOSTAL NERVE BLOCK AND LUMBAR EPIDURAL MORPHINE IN POSTTHORACOTOMY PAIN

OBJECTIVES: To compare the efficacy of continuous extrapleural interco stal nel-ve block with bupivacaine 0.5% ill 1:200 000 epinephrine and continuous lumbar epidural block with morphine in controlling post-tho racotomy pain and to measure serum bupivacaine concentrations during e xtrapleural infusion, DESIGN: A prospective, randomized, controlled tr ial, SETTING: St, Joseph's Hospital, Hamilton, Ont., a tertiary care t eaching centre. PATIENTS: Sixty-One patients booked for elective thora cotomy were randomized by sealed envelope to two groups, INTERVENTIONS : Group A received a continuous extrapleural intercostal nerve block w ith bupivacaine 0.5% in 1:200 000 epinephrine as a bolus of 0.3 mL/kg followed by an infusion of 0.1 mL/kg every hour for 72 hours, Group B received a continuous lumbar epidural block with morphine as a bolus o f 70 g/kg followed by an infusion of 7 g/kg every hour for 72 hours, M AIN OUTCOME MEASURES: Pain was assessed by a linear visual analogue sc ale (VAS) pain score, The cumu lative amount of ''rescue'' intravenous morphine used, and serum bupivacaine concentrations Here measured as secondary outcomes, RESULTS: Pain control was the same in both groups as assessed by linear VAS score ip = 0.33), The cumulative dose of int ravenous morphine for supplemental analgesia was statistically signifi cant between the groups: group A patients used more morphine than grou p B (p < 0.05), Accumulation of serum bupivacaine was present with no clinical toxicity. CONCLUSIONS: There is no significant difference in the degree of post-thoracotomy pain control measured by the VAS score when analgesia is provided by continuous extrapleural intercostal nerv e block with bupivacaine 0.5% in 1:200 000 epinephrine or lumbar epidu ral block with morphine, Larger amounts of rescue analgesia were used by patients in the continuous extrapleural group with bupivacaine than those in the continuous lumbar epidural block with morphine, Serum bu pivacaine concentrations rise without clinical toxicity.