Comparison of onset and duration of Blockade between equipotent doses of Ropivacaine-fentanyl and bupivacaine- Fentanyl in lower abdominal surgeries under Spinal anaesthesia – a one year hospital based Randomized clinical study

Abstract

Background and Objectives ABSTRACT Effective analgesia with early ambulation is becoming more important, especially for day care patients. Hence the present study was undertaken to compare the isobaric 0.75% Ropivacaine with isobaric 0.5% Bupivacaine after the addition of Fentanyl to both the groups. Methods This one year hospital based randomized clinical study was conducted from January 2012 to December 2012 in KLES Dr. Prabhakar Kore Hospital and Medical Research Centre, Belgaum, on 80 patients, undergoing elective lower abdominal surgeries under spinal anaesthesia. Patients were distributed into two groups of 40 each i.e Group B ( 2.5 cc of 0.5% Bupivacaine plus 0.5 cc of Fentanyl ) and Group R ( 2.5 cc of 0.75% Ropivacaine plus 0.5 cc Fentanyl ) . Results Both groups were comparable with respect to demographic data and hemodynamic parameters. Mean onset time of sensory block was significantly high in group R ( 7.68±1.02 v/s 5.08±0.83 minutes; p<0.001) . In group R, majority of the patients ( 90% ) achieved T the patients ( 75% ) achieved T 4 to T 6 6 to T 8 whereas in group B, majority of highest sensory block level. The duration of sensory block in group R was comparable to group B ( 133.25±11.85 v/s 137.50±11.04 minutes; p=0.101) . Time taken for onset of motor block was significantly high in group R ( 8.78±0.89 v/s 6.65±0.92 minutes; p<0.001) . The duration of total motor block ( 144.75±10.86 v/s 189.75±16.09 minutes; p<0.001) IV was significantly less in group R and the time to request for first post-operative rescue analgesia ( 230.25 ± 20.69 v/s 238.75±24.72 minutes p> 0.05) was comparable in both the groups. Conclusion and interpretation To conclude, Ropivacaine-Fentanyl required more time for onset of sensory and motor block and provided lower block level. The duration of motor block was less with comparable duration of sensory block and the time to request for first post-operative rescue analgesia in comparison to intrathecal Bupivacaine- Fentanyl.