THE EFFECT OF DIFFERENT ANESTHETIC AGENTS IN HEARING-LOSS FOLLOWING SPINAL-ANESTHESIA

The cause of hearing loss after spinal anaesthesia is unknown. Up unti l now, the only factor studied has been the effect of the diameter of the spinal needle on post-operative sensorineural hearing loss. The ai m of this study was to describe this hearing loss and to investigate o ther factors influencing the degree of hearing loss. Two groups of 22 similar patients were studied: one group received 6 mL prilocaine 2%; and the other received 3 mt bupivacaine 0.5%. Patients given prilocain e were more likely to develop hearing loss (10 out of 22) than those g iven bupivacaine (4 out of 22) (P<0.05). The average hearing loss for speech frequencies was about 10 dB after prilocaine and 15 dB after bu pivacaine. None of the patients complained of subjective hearing loss. Long-term follow-up of the patients was not possible.