The pharmacokinetics of ropivacaine after four different techniques of brachial plexus blockade.
Arterial plasma concentrations of ropivacaine were measured after brachial plexus blockade using four different approaches: lateral interscalene (Winnie), posterior interscalene (Pippa), axillary and vertical infraclavicular. Four groups of 10 patients were given a single 3.75 mg.kg(-1) injection of ropivacaine 7.5 mgxml(-1). The pharmacokinetics of ropivacaine were evaluated for 1 h after local anaesthetic injection. The supraclavicular techniques (lateral and posterior) were associated with earlier and higher peak plasma concentrations of local anaesthetic than the infraclavicular techniques (axillary and vertical infraclavicular): mean (SD) values = 3.30 (0.65) microgxml(-1) vs 2.55 (0.62) microgxml(-1) (p = 0.001) in 13.4 (6.9) min vs 25.0 (10.8) min (p = 0.0002). More ropivacaine is taken up by the systemic circulation in the first hour after the supraclavicular approaches; the mean (SD) area under the concentration-time curve was larger: 2.63 (0.51) microgxml(-1).h vs 2.10 (0.49) microgxml(-1).h (p = 0.002). These results show that the technique used for brachial plexus blockade significantly influences the systemic uptake of ropivacaine.
Rettig
H C
HC
Ikazia Hospital, Department of Anaesthesia and Pain Management, Montessoriweg 1, 3083 AN Rotterdam, The Netherlands. hcrettig@hotmail.com
Lerou
J G C
JG
Gielen
M J M
MJ
Boersma
E
E
Burm
A G L
AG
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000577:Amides / Q000008:administration & dosage / Q000097:blood*; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000097:blood*; D001917:Brachial Plexus; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D000077212:Ropivacaine
D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine