A novel cause of intrathecal baclofen overdosage: lessons to be learnt.

CASE PRESENTATION: A serious intrathecal baclofen overdose occurred in a 45-year-old woman with primary progressive multiple sclerosis following a catheter dye study with concomitant change in baclofen concentration. The pump and catheter were emptied of baclofen 2000 microg/mL, refilled and primed with baclofen 1000 microg/mL. No correction was made for the ;dead space' between the reservoir and catheter access port, which contained baclofen 2000 microg/mL. Failure of the priming bolus to account for the residual baclofen concentration within the dead space resulted in a serious overdose.Action: Amendments are being made to both our local and the Medtronic protocols. CONCLUSION: We hope that by reporting this incident the risk of this potentially fatal error re-occurring is minimized.