D. Grace et al., POSTOPERATIVE ANALGESIA AFTER COADMINISTRATION OF CLONIDINE AND MORPHINE BY THE INTRATHECAL ROUTE IN PATIENTS UNDERGOING HIP-REPLACEMENT, Anesthesia and analgesia, 80(1), 1995, pp. 86-91
Postoperative analgesia after intrathecal co-administration of clonidi
ne hydrochloride (75 mu g) and morphine sulfate (0.5 mg) was compared
with analgesia produced after either intrathecal morphine (0.5 mg) or
0.9% sodium chloride in 90 patients undergoing total hip replacement u
nder bupivacaine spinal anesthesia. Patient-controlled morphine requir
ements were significantly reduced (P < 0.001) postoperation by both cl
onidine/morphine (median 5 mg/24 h) and morphine (median 7 mg/24 h) co
mpared with control (saline) (median 28 mg/24 h). However, no signific
ant additional reduction in postoperative analgesic requirements was s
hown with the clonidine/morphine combination compared with morphine al
one. Visual analog pain scores, although good in all groups at all tim
es, were significantly poorer in the control group at 2 h (P < 0.04) a
nd 4 h (P < 0.001) after operation compared with both treatment groups
, and significantly poorer than the clonidine/morphine group at 6 h (P
< 0.002) and 24 h (P < 0.009) postoperation. Mean arterial blood pres
sure was significantly lower in the clonidine/morphine group than in t
he two other groups (P < 0.001) between 2 and 5 h after operation. The
incidence of emesis was similar in the clonidine/morphine and morphin
e groups and was significantly more than in the control group.