An open study of ropivacaine in extradural anaesthesia.
Ropivacaine 0.5%, 0.75% and 1.0% was investigated in an open study of extradural anaesthesia in three groups of 15 patients undergoing urological or orthopaedic surgery. Following a test dose of 3 ml of 1.0% lignocaine with 1:200,000 adrenaline, ropivacaine 20 ml was given in incremental doses over 4 min via a lumbar extradural catheter. The onset time for analgesia was short in all groups: T12 was blocked 4-6 min after the end of the injection of ropivacaine. The maximum segmental level was significantly higher in the 0.75% and the 1.0% groups (T2) than in the 0.5% group (T5). Complete motor block was obtained in seven, four and nine patients in the 0.5%, 0.75% and the 1.0% groups, respectively. Duration of analgesia increased with increasing concentration of ropivacaine: mean duration of analgesia was 203 and 266 min at T10 and 253 and 314 min at L5 for the 0.5 and 1% solutions, respectively. Mean duration of complete motor block was 94 and 192 min for the same solutions. Analgesia was satisfactory for surgery in all patients except for one in the 0.75% group. Hypotension was experienced by three, seven and three patients in the 0.5%, 0.75% and 1.0% groups, respectively. Bradycardia occurred in seven patients and was associated with hypotension in five. Backache was experienced after operation by four patients, and three patients complained of a brief mild headache. No late adverse events were seen.
Department of Anaesthetics, St Thomas' Hospital, London.
E
E
Whitehead
B
B
Arrigoni
J
J
Bannister
D000577:Amides / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology; D000767:Anesthesia, Epidural; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D015337:Multicenter Studies as Topic; D009407:Nerve Block; D000077212:Ropivacaine; D013997:Time Factors
D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine