The infection risk of intrathecal drug infusion pumps after multiple refill procedures

The objective of this study was to evaluate the long-term infection risk from refilling intrathecal drug delivery devices. We studied 25 patients (14 females and 11 males) with intrathecal infusion pumps placed for spasticity (23 patients) and chronic pain (two patients). In this study group there were 890 refill procedures (mean 35.6 ± 20.5; range 8-72 times) performed on an outpatient basis by four different physicians. All refill procedures were performed in a sterile and standardized fashion as suggested by the manufacturer, using manufacturer's approved kits for the refills. During the study period, five patients had recurrent infection of the urinary tract and three patients had recurrent infections of the respiratory tract. At the last pump refill of each patient, residual drug, extracted from the pump reservoir, was sent to a laboratory for aerobic and anaerobic cultures. All cultures, in all pumps, were negative for aerobic and anaerobic bacteria. We conclude that periodic refills of intrathecal implanted pumps do not seem to be a risk factor for infection if standard sterile refill procedures are performed. In this study, it was clear that comorbid infections from other parts of the body do not present as a risk for device contamination.