Morphine에 의한 진통에 대한 calcium-channel blocker의 효과 = Effect of Calcium-channel Blocker on Morphine-induced Analgesia

다국어 초록 (Multilingual Abstract)

Several previous studies have indicated that intrathecally administered calcium channel blockers potentiate the analgesic effects of intrathecally administered opioids. Furthermore, it has been reported that the systemically administered verapamil potentiate the antinociceptive effects of systemically administered morphine. The present study examined the analgesic effect of intravenously coadministered verapamil and morphine in humans.
After informed consent, we have studied 52 ASA class 1 or 2 pationts scheduled for cesarean section under general anesthesia. Patients were randomized into two groups as follows. Group 1 patients(n=22) received only morphine 0.5mg/h as a background infusion with a lmg bolus and a lockout interval of 10min during the first 24 hour by intravenous PCA. Group 2 patients(n=30) used the same PCA mode with group 1, received solution added 0.2% verapamil(0.2mg/h) to group 1 solution (morphine 0.5mg/ml). Systolic and diastolic blood pressure, heart rate, morphine requirement and pain score(1-5) were recorded in lhr, 4hr and 24hr after surgery.
The mean dose of morphine requirement for 24 hour was significant decrease in group 2(35.3±10.1 in group 1, and 26.5±10.4mg in group 2). There was no difference in pain score between the two groups and patient satisfaction was similar.
Coadministration of intravenous morphine and verapamil allowed significant reduction in morphine requirement and showed decreases in systolic and diastolic blood pressure. Our data suggest, that, by adjusting the dose of morphine and varapamil used in these combinations, the incidence of postoperative myocardial ischemia or infartion may be decreased with increasing the anaigesic effect of these drugs.