Smart central venous port for early detection of bacterial biofilm related infections

Abstract

Central venous catheters (CVC) are commonly used in clinical practice to improve a patient's quality of life. Unfortunately, there is an intrinsic risk of acquiring an infection related to microbial biofilm formation inside the catheter lumen. It has been estimated that 80 % of all human bacterial infections are biofilm-associated. Additionally, 50 % of all nosocomial infections are associated with indwelling devices. Bloodstream infections account for 30-40 % of all cases of severe sepsis and septic shock, and are major causes of morbidity and mortality. Diagnosis of bloodstream infections must be performed promptly so that adequate antimicrobial therapy can be started and patient outcome improved. An ideal diagnostic technology would identify the infecting organism(s) in a timely manner, so that appropriate pathogen-driven therapy could begin promptly. Unfortunately, despite the essential information it provides, blood culture, the gold standard, largely fails in this purpose because time is lost waiting for bacterial or fungal growth. This work presents a new design of a venous access port that allows the monitoring of the inner reservoir surface by means of an impedimetric biosensor. An ad-hoc electronic system was designed to manage the sensor and to allow communication with the external receiver. Historic data recorded and stored in the device was used as the reference value for the detection of bacterial biofilm. The RF communication system sends an alarm signal to the external receiver when a microbial colonization of the port occurs. The successful in vitro analysis of the biosensor, the electronics and the antenna of the new indwelling device prototype are shown. The experimental conditions were selected in each case as the closest to the clinical working conditions for the smart central venous catheter (SCVC) testing. The results of this work allow a new generation of this kind of device that could potentially provide more efficient treatments for catheter-related infections.

Impedimetric method to monitor biological layer formation on central venous catheters for hemodialysis made of carbothane

“…Current prevention methods which include modifications of the inner surface by antithrombotics and antibacterial agents [2], [7], [15]- [18] are so far not sufficiently effective [1]. Only recently [19] the use of the electrochemical impedance spectroscopy has led to the development of a biosensor which can monitor the formation of a biofilm layer at the port of a venous catheter, located just under the skin. The catheter with a port similar to a tunneled catheter left entirely under the skin helps to prevent the infection which is often observed in catheters described by the authors of this study.…”

“…The fibrin sheath formed mainly by proteins on the surface of the catheter within 24 hours of its insertion into the patient's circulation promotes the subsequent adhesion of pathogens [1]. However, numerous scientists [19], [22]- [25] used bacterial cultures (neglecting the influence of the proteins) for providing a characterization of biofilm growth, e.g. Paredes et al used S. epidermidis [19], [22] and S. aureus [23], Ben-Yoav et al used E. coli [24], and Taeyoung et al used Pseudomonas aeruginosa [25].…”

“…However, numerous scientists [19], [22]- [25] used bacterial cultures (neglecting the influence of the proteins) for providing a characterization of biofilm growth, e.g. Paredes et al used S. epidermidis [19], [22] and S. aureus [23], Ben-Yoav et al used E. coli [24], and Taeyoung et al used Pseudomonas aeruginosa [25]. Examinations of the deposition and the growth of biofilm were recorded for frequencies range from 0.01 Hz to 400 kHz with an AC amplitude of 10 to 100 mV [19], [22]- [25].…”

“…Paredes et al used S. epidermidis [19], [22] and S. aureus [23], Ben-Yoav et al used E. coli [24], and Taeyoung et al used Pseudomonas aeruginosa [25]. Examinations of the deposition and the growth of biofilm were recorded for frequencies range from 0.01 Hz to 400 kHz with an AC amplitude of 10 to 100 mV [19], [22]- [25]. In most of the studies a standard three-electrode configuration [24], [25] or a label-free interdigitated electrode (IDAM) biosensor were used [19], [22], [23].…”

Current Research Approaches to Target Biofilm Infections.

“…Biofilm-related infections develop on mucosal surfaces and include lung infections of Cystic Fibrosis (CF) patients, chronic obstructive pulmonary diseases, otitis media, sinusitis, and chronic wound infections (10)(11)(12)(13)(14). Biofilms also commonly develop on the surfaces of medical implant devices including catheters, prosthesis, pacemakers, and intrauterine devices, to name a few, and are responsible for 50% of nosocomial infections that occur when patients have indwelling medical devices (15). Medical implants or devices such as an indwelling catheter or a respiratory apparatus are particularly susceptible to biofilm formation because the host immune response is reduced in areas of the body in contact with foreign devices (16).…”