title: Difference in analgesia following epidural blockade in patients with postoperative or chronic low back pain.
abstract: Subjective responses of continuous epidural analgesia with bupivacaine were compared in 30 patients with acute (postoperative) or chronic (low back) pain. In the acute pain patients, sensory block was 4 dermatomes at 9 h and 6 dermatomes at 64 h. Corresponding values in the chronic pain patients were 8 and 6 dermatomes respectively. Motor blockade of the lower limbs was more profound in the acute pain group. The acute pain patients had significantly better pain relief (VAS: 85-96% vs. 55-70%) and a significantly higher proportion of these patients reported a global score of 3 (excellent; 80% vs. 7%). The mean dosage of bupivacaine decreased in the acute pain group from 21.0 +/- 5.7 (mean +/- S.D.) mg/h at 9 h to 15.1 +/- 8.5 mg/h at 64 h. Corresponding values for the chronic pain group were 20.7 +/- 5.9 and 12.0 +/- 6.0 mg/h respectively. Mean plasma concentration of bupivacaine increased from 1.2 +/- 0.8 micrograms/ml at 9 h to 2.1 +/- 1.4 micrograms/ml at 64 h in the acute pain patients and was 0.8 +/- 0.3 micrograms/ml at 9 h to 1.0 +/- 1.0 micrograms/ml at 64 h in the chronic pain patients. The incidence of side effects was approximately the same in both groups. No signs of accumulation or toxic reactions to bupivacaine were seen.
authors.affiliation: Department of Anesthesia, University of Cincinnati College of Medicine, Cincinnati, OHU.S.A. Department of Anesthesia, University of Texas Medical School at Houston, Houston, TXU.S.A.
authors.forename: Prithvi P
authors.initials: PP
authors.lastname: Raj
authors.forename: Donna
authors.initials: D
authors.lastname: Knarr
authors.forename: Ellen
authors.initials: E
authors.lastname: Vigdorth
authors.forename: Richard V
authors.initials: RV
authors.lastname: Gregg
authors.forename: Donald D
authors.initials: DD
authors.lastname: Denson
authors.forename: Hakan H
authors.initials: HH
authors.lastname: Edström
mesh_terms: D000328:Adult; D000368:Aged; D000698:Analgesia; D000767:Anesthesia, Epidural; D001416:Back Pain / Q000628:therapy*; D002045:Bupivacaine; D005260:Female; D006801:Humans; D008297:Male; D009407:Nerve Block; D010149:Postoperative Pain / Q000628:therapy*
chemical_list: D002045:Bupivacaine