Catheter-related Infections in long-term catheterized dogs. Observations on pathogenesis, diagnostic methods, and antibiotic lock technique

Background: Intravascular catheters are associated with severe infections i n patients, but only few reports on this problem in animal research exist. Objective: We report on catheter-releated bacterial colonization and its co nsequences in long-term catheterized animals. Material and Method: Foxhounds were instrumented with intravascular cathete rs and flow probes to study the regulation of renal blood flow and pressure s. Results: After flushing the catheters, alterations in renal blood flow were observed and these could be related to bacterial colonization of intravasc ular catheters with Pseudomonas species. After attention had been focused o n aseptic technique in all experimental phases and prophylactic antibiotic lock instituted, the occurrence of Pseudomonas bacteremia ceased, and the m agnitude and incidence of catheter-related colonization and infection by Ps eudomonas species dropped considerably. Conclusion: The catheter-related colonization that occurred spontaneously i n these animals resembled findings in animal experiments in which catheter- related infections were deliberately induced as well as observations made w ith regard to catheter-related infections in patients. This report emphasiz es the importance of asepsis when working with animals with long-term intra vascular catheters. We suggest that monitoring for this complication, e.g., by means of catheter cultures at the: time of removal, should routinely be part of protocols for animal experiments using long-term intravascular cat heters.