Effects of different time administration of parecoxib sodium on acute opioid tolerance after remifentanilbased anesthesia

Abstract

Objective To investigate the effects of different time administration of parecoxib sodium on acute opioid tolerance after remifentanil-based anesthesia in patients.Methods Fifty-four ASA Ⅰ or Ⅱ patients aged 30-64 yr undergoing transabdominal cholecystectomy were randomly divided into 3 groups(n=18 each):group I received parecoxib 40 mg at 30 rain before anesthesia;group Ⅱ received parecoxib 40 mg at 30 min before termination of anesthesia;group C control.Anesthesia was induced and maintained with propefol and remifentanil administered via TCI.The target plasma concentration of propofol was set at 3μg/ml and that of remifentanil at 4 ng/ml.Tracheal intubation was facilitated with rocuronium 0.6 ms/ks.Muscle relaxation was maintained with intermittent iv boluses of vecuronium during operation.Pain was assessed using behavioral pain score(O=quiet and no pain,1=complaining,2=severe pain and/or agitation).When the pain score >0,the patients received iv injection of morphine and then PCIA with morphine(bolus dose 1 mg,lockout interval 5 min,no background infusion)30 min later.Morphine consumption and side effects were recorded within 30 min,and during 30 min-24 h and 24-48 h after operation.Results Compared with group C,the morphine consumption was significantly decreased during all the time periods within 48 h after operation in group I and during 30 rain-24 h and 24-48 h after operation in groupⅡ(P<0.05).The morphine cousumption was significantly higher within 30 min after operation in group Ⅱ than in group Ⅰ (P<0.05).No obvious side effects occurred in the 3 groups.Conclusion Parecoxib sodium 40 mg given before anesthesia can reduce acute opioid tolerance after remifentanil-based anesthesia in patients. Key words: Cyclooxygenuse inhibitors; Piperidines; Analgesics,opioid; Drug tolerance