Effects of ropivacaine concentration on the spread of sensory block produced by continuous thoracic paravertebral block: a prospective, randomised, controlled, double-blind study.
Factors affecting the distribution of continuous thoracic paravertebral block have never been examined. We designed this prospective, double-blind study to check whether continuous thoracic paravertebral block with a higher ropivacaine concentration would provide a wider segmental sensory block spread. Sixty consecutive patients undergoing pulmonary lobectomy or segmentectomy were randomly allocated to receive continuous paravertebral infusion of either 0.2% or 0.5% ropivacaine (6 ml.h(-1) ). The primary outcome was the number of anaesthetised dermatomes as determined by loss of cold sensation 24 h after surgery. Twenty-seven patients per group were included in the final analysis. The median (IQR [range]) number of anaesthetised dermatomes 24 h after surgery was 4 (3-6 [1-9]) with ropivacaine 0.2% and 4 (3-6 [2-11]) with ropivacaine 0.5% (p = 0.66). Contrary to our expectation, the segmental spread of sensory block produced by continuous thoracic paravertebral block does not depend on ropivacaine concentration.
Division of Anesthesiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata-city, Japan.
T
T
Yoshida
T
T
Fujiwara
K
K
Furutani
N
N
Ohashi
H
H
Baba
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000577:Amides / Q000008:administration & dosage / Q000494:pharmacology*; D000768:Anesthesia, General; D000771:Anesthesia, Intravenous; D018686:Anesthetics, Intravenous; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D005283:Fentanyl; D006801:Humans; D008168:Lung / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009407:Nerve Block; D020250:Postoperative Nausea and Vomiting / Q000453:epidemiology; D011446:Prospective Studies; D000077212:Ropivacaine; D018084:Ultrasonography, Interventional; D055815:Young Adult
D000577:Amides; D018686:Anesthetics, Intravenous; D000779:Anesthetics, Local; D000077212:Ropivacaine; D005283:Fentanyl