Higher Than Expected Residual Volumes of Intrathecal Baclofen – A Brief Report

Intrathecal baclofen (ITB) pumps deliver baclofen effectively, but pump or catheter failures can have severe consequences. Early identification of dysfunction is crucial. In our retrospective single-site study, we evaluated whether the calculated residual baclofen volume discrepancies of -15% to -25% at routine ITB pump refills may indicate catheter dysfunction. We assessed 14 patients (11 males) undergoing 56 ITB pump refills over 12 months. One patient averaged errors of -17% over six refills and subsequently presented in acute baclofen withdrawal. Our findings suggest that volume discrepancies greater than -15% could warrant a high index of suspicion for ITB catheter or pump issues.