Intrathecal Pump Refills, Pocket Fills, and Symptoms of Drug Overdose: A Prospective, Observational Study Comparing the Injected Drug Volume vs. the Drug Volume Effectively Measured Inside the Pump.

A volume discrepancy of >1 mL in 20 mL IDDSs and of >2 mL in 40 mL IDDSs after refill should be regarded as potentially consequential with regard to risk of overdose possibly caused by a pocket fill. In case of potentially consequential volume discrepancies, hospitalization and monitoring is recommended to preclude late overdose symptoms outside the hospital.