Objective. Effective postoperative pain control reduces
postoperative morbidity. In this study, we investigated
the effects of intrathecal morphine,
ketamine, and their combination with bupivacaine
for postoperative analgesia in major abdominal cancer
surgery.
Study Design. Prospective, randomized, doubleblind.
Setting. Academic medical center.
Patients and Methods. Ninety ASA I–III patients age
30 to 50 years were divided randomly into three
groups: the morphine group (group M) received
10mg of hyperbaric bupivacaine 0.5% in 2mL volume
and 0.3mg morphine in 1mL volume intrathecally.
The ketamine group (group K) received
0.1 mg/kg ketamine in 1mL volume instead of morphine.
The morphine1ketamine group (group
K1M) received both 0.3mg morphine and 0.1mg/kg
ketamine in 1mL volume intrathecally. Postoperative
total morphine consumption, first request of analgesia,
visual analog score (VAS), and side effects were
recorded.
Results. Total PCA morphine was significantly decreased
in group M1K compared with groups M
and K. Time to first request of analgesia was prolonged
in groups M and M1K compared with group
K (P < 0.001). VAS in group M1K was reduced from
two to 24 hours, and in group M from 12 and
18 hours postoperation compared with group K,
with an overall good analgesia in the three groups.
Sedation was significantly higher in group M1K
compared with group M until six hours postoperation.
No other side effects were observed.
Conclusions. Adding intrathecal ketamine 0.1mg/kg
to morphine 0.3mg in patients who underwent major
abdominal cancer surgery reduced the total postoperative
morphine consumption in comparison with either
drug alone, with an overall good postoperative
analgesia in all groups, with no side effects apart
from sedation.