The influence of lidocaine on the permeability of the blood-cerebrospinal fluid barrier in experimental acute hypercapnia in the rabbit

In a previous study we have provided evidence, that acute experimental hype rcapnia due to hypoventilation in the rabbit alters blood-cerebrospinal flu id barrier function in the brain (Pakulski et al. 1998). The purpose of thi s study therefore was to determine if lidocaine would prevent the observed alterations in the blood-cerebrospinal fluid barrier function. The experime nts were conducted in 16 adult Chinchilla rabbits submitted to acute hyperc apnia due to mechanical hypoventilation (PaCO2 between 8 - 9.5 kPa over 180 minutes) under pentobarbital anaesthesia. The studied group (n = 8) was tr eated by lidocaine infusion 10 mg kg(-1) h(-1). After 180 minutes of hyperc apnia the value of cerebrospinal fluid-blood index of gentamycin concentrat ion, indicating the permeability of the blood-cerebrospinal fluid barrier, was significantly lower in animals treated with lidocaine (4.03 +/- 2.32 vs . 19.05 +/- 5.49; P < 0.01). We conclude that lidocaine may attenuate the i ncrease of blood-cerebrospinal fluid barrier permeability under conditions of experimental acute hypercapnia lasting 180 minutes in the mechanically v entilated rabbit.