Background:
@EN Preemptive analgesia may prevent nociceptive inputs generated during surgery from sensitizing neurons, and therefore, may reduce post-operative pain. But, preemptive analgesia has been shown to decrease postinjury pain in animals, studies in
human
have provided controversial results. We studied whether intravenous morphine infusion before induction could affect post-operative pain and analgesic demands, when compared with intravenous morphine infusion after the closure of the peritoneum.
@ES Methods:
@EN Female patients scheduled for total abdominal hysterectomy were randomly assigned to one of two groups of prospectively studied in a double-blind manner. Group I(n=23) and II (n=20) received intravenous morphine(0.1mg/kg)before induction of
anesthesia and after the closure of the peritoneum, respectively. Either group had continuous infusion of morphine (1.5mg/hr) immediately after i.v. bolus morphine, Postoperative pain relief was provided with i. v morphine form a PCA system
(Medex
Walkmed(r)). Postoperative visual analogue pain scores (VAS),analgesics requirements and side effects were examined and compared between groups for 2 postoperative days.
@ES Results:
@EN VAS were significantly less in group I (3.3±0.4) than in group II (5.3±0.5) 2hrs after surgery(p<0.01). Patient-controlled morphine cumulative consumption in group I was significantly less than in group II for 24hours(219 mg vs 35.3mg) and
48hours
(37.4 mg vs 55.0mg) after operation (p<0.01).
@ES Conclusions:
@EN Preemptive analgesia with intravenous morphine reduces postoperative pain and analgesic requirements. Lower postoperative analgesic requirements in preemptive analgesic group indicate that intravenous morphine prevents development of
injury-induced
peripheral or central sensitization. (Koran J anesthesiol 1996; 30: 497~486)
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