Epidural methadone results in dose-dependent analgesia in cancer pain, further enhanced by epidural dexamethasone

Abstract

Background: This study was designed to evaluate the role of epidural methadone-lidocaine in cancer pain combined or not to epidural dexamethasone.

Methods: In all, 72 cancer patients, 32- to 67-year-old were randomized to six groups (n=12) and prospectively studied to examine analgesia and adverse effects for 3 weeks. Patients received single-dose protocol epidural test drugs: Control group (CG) received epidural 40-mg lidocaine diluted to 10-ml volume with saline. Dexamethasone group (DG) 40-mg lidocaine plus 10-mg dexamethasone. The 2.5MetG 2.5-mg epidural methadone with 40-mg lidocaine; the 5MetG, 5-mg epidural methadone plus 40-mg lidocaine, the 7.5MetG, 7.5-mg epidural methadone plus 40-mg lidocaine and finally the 7.5Met-DexG, 7.5-mg methadone with 40-mg lidocaine and 10-mg dexamethasone.

Results: Groups CG, DG and 2.5MetG were similar regarding analgesia and side effects. Patients from 5MetG and 7.5MetG took 3 ± 1 and 5 ± 1 days, respectively, to restart oral morphine. Patients from 7.5MetDG took 14 ± 2 to restart oral morphine (P<0.001). Daily somnolence and appetite improved in the 7.5MetDG during 2-week evaluation (P<0.005). Fatigue improved for both DG and 7.5MetDG during 2-week evaluation (P<0.005). By the third week of evaluation, all patients were similar.

Conclusions: Epidural methadone plus lidocaine resulted in dose-dependent analgesia, further improved by epidural dexamethasone, which also improved fatigue.

Figure 1

Daily consumption of oral morphine in the groups. CG=control group; 2.5MetG=2.5 mg methadone group; 5MetG=5 mg methadone group; 7.5MetG=7.5 mg methadone group; 7.5MetDG=7.5 mg methadone-dexamethasone group. Day-1=the CG, DG and 2.5MetG kept the daily oral consumption of 80–90 mg morphine (P>0.05). CG=DG=2.5MetG during all the 21-day evaluation regarding oral daily morphine consumption (P>0.05). Patients started the evaluation on day-1 taking 80–90 mg oral morphine, which was gradually increasing for CG, DG and 2.5MetG until day-21 (150–170 mg morphine) (daily evaluation-P>0.05) 5MetG=from day-1 to day-3, the daily intake of oral morphine was: 5MetG=7.5MetG=7.5MetDG (P>0.05) < CG=DG=2.5MetG (P<0.001). From day-4, patients started getting daily increasing oral morphine intake, which was similar to the CG, DG and to the 2.5MetG from day-7 forwards (daily evaluation-P>0.05). 7.5MetG=from day-1 to day-5, the daily intake of oral morphine was: 7.5MetG=7.5MetDG (P>0.05) <CG=DG=2.5MetG (P<0.001). From day-6, patients started getting daily increasing oral morphine intake, which was similar to the CG, DG and to the 2.5MetG from day-10 forwards (daily evaluation-P>0.05). 7.5MetDG=from day-1 to day-15, the daily intake of oral morphine was lesser when compared with the CG=DG=2.5MetG (P<0.001). On day-4, 7.5MetDG <5MetG (P<0.05). On day-6, 7.5MetDG <7.5MetG (P<0.05). From day-15, the oral intake of daily morphine was similar to all groups (P>0.05).