A comparison of bacterial colonisation between Polyurethane and Polytetrafluroethylene (Teflon®) short term intravenous catheters in horses

Background: The effect of catheter material on catheter-associated complications resulting from short-term intravenous catheterisation in horses is unknown. Hypothesis: Polytetrafluroethylene catheters would have a higher incidence of positive bacterial cultures and increased clinical evidence of catheter site reaction and thrombophlebitis compared to polyurethane catheters. Methods: 36 healthy client-owned horses presented for elective surgery were randomly allocated a catheter type. Aseptic catheter placement and removal was standardised, however, antimicrobial treatment was case dependent and at the clinician's discretion. Catheters were maintained for 74 h and visually assessed for clinical evidence of catheter site reaction and thrombophlebitis twice daily. Two catheter segments were submitted for bacterial culture and antimicrobial sensitivities. Results: Bacterial isolates were cultured from 90% of polyurethane and 69% of polytetrafluroethylene catheters. Multiple isolates were found in 40% of polyurethane and 31% of polytetrafluroethylene catheters. No difference was found between the proportion of catheters with colonisation (p=0.24) or multiple isolates (p=0.85). Nor was an association identified in bacterial colonisation rates or clinical evidence of catheter-site complications between catheter types (0.9Multiple-drug resistance was identified regularly. No clinical evidence of thrombophlebitis occurred in any horse. Conclusions and Clinical Importance: In healthy horses, there is no clinical advantage for the use of polyurethane over polytetrafluroethylene catheters in short term catheter placements of less than 72 h duration.