Effect of preoperative low dose of ketamine administered epidurally or intravenously on postoperative proinflammatory interleuldn-6 response

ABSTRACT

This study was done to compare the effect of preoperative epidural versus intravenous administration of low dose of ketamine on postoperative interleukjn6 [IL-6] Production and its contribution to postoperative pain. Twenty minutes before induction of anesthesia forty five patients which were randomly assigned into 3 equal groups 0.5mg/kg ketamine administered epidurally [epid.ket.group] 0.5mg/kg ketamine administered intravenously [i.v. ket.group] and control group received i.v. 5 ml 0.9% saline. All patients received general anesthesia using isoflurane-nitrous oxide and i.v. fentanyl as needed. Postoperatively they received intermittent controlled i.v. pethidine analgesia as needed. Analgesic effects were evaluated using visual Analog Scale [VAS] pain score at 4,8,12h post operatively, time to first request for analgesic, and total first postoperative 24 hours pethidine consumption The IL-6 serum level was recorded at 4, 8 and 12 hours Postoperatively. The results of this study demonstrated that patients in epid.ket.group exhibited less severe postoperative pain [lower VAS pain score], longer duration of analgesia, lower pethidine consumption and lower IL-6 serum levels than i.v.ket.group. In conclusion preoperative epidural administration of low dose of ketamine is more effective than intravenous ketamine in attenuating the proinflammatory IL-6 response to surgery which may contribute to its more effective postoperative pain relieve