Addition of small doses of clonidine to bupivacaine in ilioinguinal and iliohypogastric nerve block following spinal anesthesia for inguinal herniorraphy

ABSTRACT

Addition of clonidine to bupivacaine improves and prolongs analgesia following central blocks. In peripheral nerve blocks, divergent results have been reported. The aim of this study was to determine the efficacy of clonidine mixed with bupivacaine on postoperative analgesia provided by an ilioinguinal and iliohypogastric nerve block following herniorrhaphy in adult patients. After institutional approval and informed consent, 60 adult patients scheduled for unilateral inguinal herniorrhaphy under spinal anaesthesia were included in this prospective and randomized study. At the end of surgery, patients received an ilioinguinal and iliohypogastric block with 20 ml of 0.25% bupivacaine mixed with 1 mcg/kg of clonidine [group I] or mixed with 1 ml of 0.9% saline [group II]. Visual Analogue Scores [0-10 cm] at rest and during mobilization, sedation, hemodynamic variation and first analgesic request were recorded at 2, 6, 12, 18 and 24 postoperative hours. Statistical analysis was performed by two-way ANOVA, Fisher, Student and Mann-Whitney tests. PDemographic data were comparable among groups. There was no significant difference between the two groups in term of pain scores at rest [p=0.5] and during mobilization [p=0.8] or side effects. First analgesic request was comparable among groups [31 +/- 20 h in group I v/s 21 +/- 20 h in group II; p=0.01]. Addition of small doses of clonidine to bupivacaine in ilioinguinal and iliohypgastric block does not improve or prolong analgesia following inguinal hernia repair. No specific side effects were found