[Post-thoracotomy analgesia and serum concentration of epidurally administered morphine; a pharmacokinetic and pharmacodynamic study].
Twenty patients who underwent thoracotomy were given 2mg of epidural morphine postoperatively. Serum morphine concentrations were determined, analyzed pharmacokinetically, and compared with the degree of analgesia obtained. Excellent analgesia was attained in 11 patients and fair analgesia in the remaining 9 patients. Onset of analgesia was at 15.8 +/- 4.8 mins and 24.7 +/- 3.5 mins in the excellent and fair analgesia groups, respectively. This difference in time was statistically significant (P less than 0.05). There was no significant difference in the duration of analgesia between the two groups. Maximal concentration (Cmax) was calculated to be 38.5 +/- 4.2 ng.ml-1 in the excellent analgesia group and 25.7 +/- 4.3 ng.ml-1 in the fair group. The area under the concentration-time curve (AUC) in the fair group was approximately 20% of that in the excellent group. It is concluded that serum morphine levels correlated with analgesic effect in patients receiving epidural morphine after thoracotomy.
Takahashi
K
K
D000328:Adult; D000368:Aged; D015360:Analgesia, Epidural; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000097:blood / Q000493:pharmacokinetics*; D010149:Postoperative Pain / Q000517:prevention & control*; D013908:Thoracotomy
D009020:Morphine