Mini-dose (0.05 mg) intrathecal morphine provides effective analgesia after transurethral resection of the prostate.
OBJECTIVE
To determine the optimal dose of intrathecal morphine that produces satisfactory analgesia with minimum side effects in elderly patients undergoing transurethral resection of the prostate (TURP).


METHODS
In this double-blind prospective study, 42 patients undergoing TURP with spinal anesthesia were allocated to one of three groups. Group A (n = 14) received tetracaine, 10 mg, alone. Group B (n = 13) and Group C (n = 15) received morphine 0.05 mg and 0.10 mg, respectively, in combination with tetracaine. Postoperative pain, nausea and pruritus were evaluated using visual analogue scales (VAS). SpO(2) and respiratory rate were also assessed.


RESULTS
At three, five, seven and 24 hr after spinal anesthesia, the VAS scores for pain in Groups B and C were significantly less than in Group A. Group C experienced significantly greater VAS scores for pruritus as compared to Groups A and B. There was no significant difference in the intensity of nausea among the three groups. No patient experienced hypoxemia (SpO(2) < 90%) and respiratory depression (respiratory rate < 10 beats*min(-1)) in any group.


CONCLUSIONS
A dose of 0.05 mg in intrathecal morphine with spinal anesthesia would be optimal for elderly patients undergoing TURP.
Sakai
Tetsuya
T
Departments of Anesthesiology, Nagasaki University School of Medicine, and the Sasebo Kyosai Hospital, Nagasaki, Japan.
Use
Tadasuke
T
Shimamoto
Hiroko
H
Fukano
Taku
T
Sumikawa
Koji
K
D000368:Aged; D000369:Aged, 80 and over; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000627:therapeutic use; D004311:Double-Blind Method; D006801:Humans; D007278:Injections, Spinal; D008297:Male; D009020:Morphine / Q000008:administration & dosage* / Q000627:therapeutic use; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D020728:Transurethral Resection of Prostate; D016896:Treatment Outcome
D000701:Analgesics, Opioid; D009020:Morphine