Postoperative pain relief following intrathecal bupivacaine combined with intrathecal or oral clonidine.
BACKGROUND
The purpose of the present study was to evaluate the postoperative analgesic and adverse effects of equal doses of oral or intrathecal clonidine in spinal anaesthesia with bupivacaine plain.


METHODS
Forty-five ASA I-III orthopaedic patients scheduled for osteosynthesis of a traumatic femur fracture were randomised in a double-blind fashion to one of 3 groups. Patients received 15 mg of plain bupivacaine intrathecally (group B) or an intrathecal mixture of bupivacaine 15 mg and clonidine 150 mg (group CIT). In group CPO oral clonidine 150 mg was administered 60 min before intrathecal injection of bupivacaine 15 mg.


RESULTS
Oral and intrathecal clonidine prolonged the time until the first request for analgesics, 313 +/- 29 and 337 +/- 29 min, respectively, vs. 236 +/- 27 min in group B (P < 0.01). The total 24- h PCA morphine dose was significantly lower in group CIT(19.3 +/- 1.3 mg) compared to groups B and CPO(33.4 +/- 2.0 and 31.2 +/- 3.1 mg). MAP was decreased significantly during the first hour after intrathecal clonidine(14%) and during the first 5 h after oral clonidine(14-19%). HR decreased in CIT during the 5th and 6th postoperative hours(7-9%) and during the first 2 h(9%) in CPO (P < 0.01). The degree of sedation was more pronounced in group CPO during the first 3 h. Four patients had pruritus in group B.


CONCLUSIONS
Addition of intrathecal clonidine prolonged analgesia and decreased morphine consumption postoperatively more than oral clonidine. Hypotension was more pronounced after oral than after intrathecal clonidine. Intrathecal clonidine is therefore recommended.
Department of Anesthesiology and Intensive Care, Orebro University Hospital, Sweden. igor.dobrydnjov@orebroll.se
I
I
Dobrydnjov
K
K
Axelsson
J
J
Samarütel
B
B
Holmström
D000284:Administration, Oral; D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage*; D000328:Adult; D000700:Analgesics / Q000008:administration & dosage*; D000775:Anesthesia, Spinal; D019162:Anesthetics, Combined / Q000008:administration & dosage*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001794:Blood Pressure; D002045:Bupivacaine / Q000008:administration & dosage*; D003000:Clonidine / Q000008:administration & dosage*; D004311:Double-Blind Method; D005260:Female; D005264:Femoral Fractures / Q000601:surgery; D005593:Fracture Fixation, Internal; D006339:Heart Rate; D006801:Humans; D007278:Injections, Spinal; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000188:drug therapy*
D000316:Adrenergic alpha-Agonists; D000700:Analgesics; D019162:Anesthetics, Combined; D000779:Anesthetics, Local; D003000:Clonidine; D002045:Bupivacaine