Comparison of the pharmacological properties of 0.375% bupivacaine with epinephrine, 0.5% ropivacaine and a mixture of bupivacaine with epinephrine and lignocaine - a randomized prospective study.

One of the methods of anesthesia for orthopedic and plastic procedures for the upper limb is the brachial plexus block. The aim of the study was to compare the pharmacodynamic and pharmacokinetic properties of three commonly used local anesthetic solutions used for axillary brachial plexus blockade. Sixty patients scheduled for surgery of the upper limb were enrolled for the study. 3 different local anesthetic solutions: 0.375% bupivacaine with epinephrine (group B), 0.5% ropivacaine (group R) and a mixture of 0.5% bupivacaine with epinephrine and 2% lignocaine in a 1:1 ratio (group BL) were used to anesthesia. The study assessed the delay time of sensory and motor blockade and the duration of sensory and motor anesthesia of the operated limb. There were no significant differences in the onset of sensory block between the study groups. In the BL group, the onset of the motor block was significantly shorter than in group B and group R. The duration of the sensory and motor blockade was significantly longer in group B and group R than in the group BL. The solution of 0.375% bupivacaine with epinephrine and 0.5% ropivacaine used for axillary brachial plexus anesthesia provide the same level of the block. Addition of short acting local anesthetic - lignocaine to long acting bupivacaine decreases the time to onset of motor blockade, but also shortens the duration of the sensory and motor blockade in the post-operative period, compared to long acting local anesthetics of higher potency: bupivacaine with epinephrine or ropivacaine.