title: Comparison of bupivacaine and alkalinized bupivacaine in brachial plexus anesthesia.
abstract: To define the effect of alkalinization of bupivacaine 0.5% in subclavian perivascular brachial plexus blockade, the time to onset, time to peak effect, and 6-hour regression of sensory and motor blockade were determined. Sixty physical status ASA I and II patients were randomly allocated to one of two groups and a double-blind design was used: group I (n = 30) received bupivacaine 0.5% (pH, 5.5) 3 mg/kg, while group II (n = 30) received alkalinized bupivacaine 0.5% (pH, 7.05-7.15) 3 mg/kg. Onset and regression of sensory blockade were determined by pinprick in the C4-T2 skin dermatomes, while motor blockade was assessed using a scheme of proximal to distal muscle group paralysis. Time to onset of sensory blockade (group I, 4.0 +/- 1.2 min; group II, 3.6 +/- 0.9 min) and time to peak sensory effect (group I, 17.7 +/- 1.8 min; group II, 16.3 +/- 1.8 min) did not differ significantly between the groups. Similarly, no difference in time to onset of motor blockade (group I, 6.9 +/- 1.7 min; group II, 6.3 +/- 1.5 min) or time to peak motor effect (group I, 18.1 +/- 1.9 min; group II, 15.1 +/- 1.9 min) was observed. Regression of postoperative sensory and motor blockade was similar in both groups. It is concluded that alkalinization of bupivacaine 0.5% solutions does not confer any added clinical advantage in subclavian perivascular brachial plexus blockade when compared with commercially available bupivacaine.
authors.affiliation: Department of Anesthesia, University of Manitoba, Winnipeg, Canada.
authors.forename: M D
authors.initials: MD
authors.lastname: Bedder
authors.forename: R
authors.initials: R
authors.lastname: Kozody
authors.forename: D B
authors.initials: DB
authors.lastname: Craig
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000762:Anesthesia Recovery Period; D001132:Arm / Q000601:surgery; D001917:Brachial Plexus / Q000187:drug effects*; D002045:Bupivacaine / Q000008:administration & dosage; D004341:Drug Evaluation; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D009407:Nerve Block; D011897:Random Allocation; D013997:Time Factors
chemical_list: D002045:Bupivacaine