Fig. 3. Tissue-to-plasma partition coefficients and intracerebral volume of distribution of lidocaine, bupivacaine, and levobupivacaine. (A –C ) Tissue-to-plasma partition coefficients (K  ^p, K  ^p,u, and K  ^p,uu) and (D ) volume of distribution (V  ^u,br) of the unbound fraction of lidocaine, bupivacaine, and levobupivacaine in the brain. Data are expressed as the mean ± SD of 12 experiments. *P < 0.05, **P < 0.01 compared with lidocaine, ‡P < 0.01 compared with bupivacaine or levobupivacaine.