Infections related to intrathecal baclofen therapy in children and adults: frequency and risk factors

Abstract

Object The purpose of this study was to determine the frequency of infection and to identify risk factors for infection in connection with the implantation of an intrathecal baclofen (ITB) pump. Methods This retrospective study included all pediatric and adult patients who received ITB at Rikshospitalet during the years 1999–2005. A database was created that included the following variables: patient age, sex, weight, diagnosis, surgical procedure performed, presence of a percutaneous endoscopic gastrostomy (PEG) tube, urinary as well as fecal incontinence, anesthetist's classification of patient status (American Society of Anesthesiologists grade), timing of antibiotics administration, surgeon, assisting nurse, and surgical procedure time. Moreover, the mode of intrathecal screening trial (transcutaneous vs subcutaneous catheter insertion) and any complications were registered. The authors differentiated between deep and superficial infection, and they registered the causative agent. Results A total of 163 patients received ITB; of these, 91 were pediatric patients (median age 10 years), and 72 were adults (median age 44 years). A total of 408 surgical procedures were performed. No infections occurred in direct relation to the screening trials. When a pump was implanted subsequent to a screening trial with transcutaneous catheter insertion, the rate of infection was 9% in the pediatric patients. The corresponding infection rate for pumps implanted after a screening trial with a subcutaneous distal catheter (Albright method) was 12%. This difference was not significant. There was a significantly higher incidence of deep infections following pump implantation in the pediatric group (p = 0.028) than in the adult group. The presence of a PEG tube increased the incidence of infection (p = 0.008) and may be one of the main reasons for a higher frequency of infections in children. When the patient suffered urinary and/or fecal incontinence, there was a higher chance of infection (p = 0.021). The surgical time was significantly longer in the pediatric group than in adults; however, the length of the surgical procedure had no impact on the occurrence of infection. The most common causative agent was Staphylococcus aureus; this microbe was responsible for 69% of deep infections. Also, 69% of deep infections occurred within 1 month after surgery. Conclusions The rate of infection is significantly higher in children undergoing ITB pump implantation than it is in adults. Screening trials applying the Albright method fail to reduce the frequency of infection subsequent to pump implantation. The presence of a PEG tube has the greatest significance as a predictor of infection.