Recovery after brain injury--some neurotransmitter and clinical implications.

tcrs and optimal positioning of the patient, for best effect. In investigating the technique, I chose to use large volumes of 0.5% bupivacaine, but only in an attempt to ensure that volume and concentration of local anaesthetic could not be implicated in failed blockade. I have no doubt, from subsequent personal experience, that tmalW volumes and concentrations of local anaesthetic can provide an equally satisfactory and a safer block. Perhaps, with further investigation, one may indeed find, as Dr Dawson suggests, that eztradural catheters in alternate intercostal spaces, provide the best answer, notwithstanding the greater danger of pleura] puncute. Finally, I would concur with Dr Dawson in saying that Tuohy needles are in general too bhmt for this technique. I have found, however, that the disposable Tuohy needles manufactured by Portez (U.K.) Ltd are extremely sharp and admirably suitable for this purpose. D. F. MURPHY Dublin