Fig. 2From: Effects of a fixed low-dose ropivacaine with different volume and concentrations on interscalene brachial plexus block: a randomized controlled trialKaplan-Meier survival curves constructed using survival as being equivalent to an “unsuccessful block.” The onset of sensory (a) and motor (b) blockade was shorter in patients receiving higher concentration of ropivacaine (P = 0.000 by log-rank test)Back to article page