gms | German Medical Science

Objective: Cerebrospinal fluid (CSF) diversion through external ventricular drainage (EVD) is a standardized therapeutic intervention in hydrocephalus of different origin. The risk of bacterial infection may be decreased by using EVD catheters with antibacterial properties. This study compares the rates of CSF infection in hydrocephalus patients with two different types of antibacterial EVD catheters.

Method: This randomized prospective study was carried out in adult patients with hypertensive hydrocephalus in need of EVD. Following factors were investigated and analyzed: occurrence of microbiologically confirmed bacterial pathogens in the CSF and/or intraventricular portion of the catheter, type of pathogens, duration of EVD, and catheter replacement or removal. Patients were randomly assigned to one of two groups using either silver-coated (SC) or antibiotic-impregnated (AI) EVD catheters. Statistical significance was set at p<0.05 and Fisher's exact test was used.

Results: The study enrolled 94 patients in total, 41 males and 53 females. The mean age of the 42 patients (15 males and 27 females) in the AI group was 65 years (range 38 to 94 years). The 52 patients (26 males and 26 females) in the SI group had a mean age of 60 years (range 29 to 87 years). There were 6 patients with EVD infections in the whole study group (6.38%). In the SI group there were 5 cases of bacterial infection (9.61%). Only one infection was found in the AI group (2.38%). The difference between infections rates in both groups was however not statistically significant. In a total of 5 (5.31%) patients in both groups the EVD catheter had to be replaced because of obstruction of CSF outflow. The rate of obstruction was 9.52% (4 out of 42) in the AI group and 1.92% (1 of 52) in the SI group. This difference is not statistically significant. The mean duration of EVD in the whole group was 10 days (range 1 to 29 days), 11 days (range 1 to 29 days) in the AI group and 10 days (range 2 to 20 days) in the SI group.

Conclusions: No significant difference of the infection rates of both catheter types could be demonstrated. There was a trend for lower infection rates in the AI group. There was no statistically significant difference in the catheter obstructions and replacement rates. A trend towards more frequent obstruction and catheter replacement in the AI group was noted, which may be due to the difference of inner diameters (1.5 mm in the AI group and 1.9 mm in the SI group).