Comparison between intrathecal morphine with paravertebral patient controlled analgesia using bupivacaine for intraoperative and post-thoracotomy pain relief

OBJECTIVES: This study was designed to compare the intrathecal morphine and paravertebral block with bupivacaine given before induction of anesthesia for intra-operative and post-thoracotomy pain relief for 48 hours using patient controlled paravertebral analgesia in post-operative period. METHODS: After taken an approval from the ethics committee of the University, 40 patients were randomly assigned to receive either preservative-free intrathecal morphine 0.3 mg in 3 ml normal saline together with paravertebral block (group I) or paravertebral block alone using bupivacaine (group II) before an induction of anesthesia. No continuous infusion of bupivacaine was started in both groups. Primary outcomes were Visual Analogue Score (VAS) at rest and on coughing. Hemodynamic and respiratory effects, bupivacaine consumption, patient's satisfaction, and side effects like nausea, vomiting, urinary retention, and itching were considered as secondary outcomes. All patients in both groups received paracetamol 1 gram (gm) IV every 6 hourly for the 1(st) 24 hr. Amount of rescue analgesic (pethidine 0.5 mg/kg IV) in both groups and total bupivacaine cumulative doses in 48 hrs were calculated. RESULTS: VAS at rest and on coughing did not differ significantly between the 2 groups at 0, 1, 6, 12, 18, 24, and 48 hours (P= >0.1). At 24 hours, VAS increased in both the groups, but the increase in VAS was comparable in both groups. There were insignificant incidences of nausea, purities, and urinary retention in intrathecal group compared with paravertebral group. The other side effects and patient satisfaction did not show any statistical significant difference between 2 groups. CONCLUSION: Intrathecal morphine 0.3 mg is safe and effective way to improves pain control for thoracic surgery and was comparable to paravertebral patient control analgesia (PPCA) with bupivacaine for the 1(st) 48 hours post-thoracotomy.