Catheter-related bloodstream infections in tunneled catheters: a long-term outcomes-based approach

Tunneled catheters (TC) have become an essential vascular access for hemodialysis (HD), despite their association with increased morbidity and mortality, particularly due to infections. Existing studies assessing the optimal combination of prophylactic measures to prevent TC-related infections are limited by small sample sizes and short follow-up periods. The objectives of this study were to describe the clinical and demographic characteristics of patients with TC in our healthcare area, determine the incidence and etiology of TC-related bloodstream infections (TC-BSI), and analyze the impact of pre-implantation prophylactic measures and patient survival over a long-term follow-up.

We conducted a retrospective study including all patients with a TC implanted between 2005 and 2019 in a tertiary care hospital. Catheter implantation was performed by nephrologists following a protocol developed in collaboration with the Infectious Diseases Department. The protocol emphasized three main measures: screening and treatment of Staphylococcus aureus carriers, chlorhexidine bathing prior to the procedure, and antibiotic prophylaxis. We collected clinical-demographic variables, catheter-related data, and details of TC-BSI episodes. Patients were followed from the time of TC insertion until the end of the study (December 31, 2020), loss to follow-up, or death.

Over the 14-year study period, 462 TCs were implanted in 381 patients [179 (55.1%) male; median age 67 (IQR 55-74) years; 154 (47.4%) with diabetes mellitus, 292 (89.9%) with hypertension, and 135 (41.5%) with cardiovascular disease]. The internal jugular vein was the most common site of insertion (275, 84.6%). Two types of catheters were predominantly used: Palindrome® (192, 59.1%) and Hemoglyde® (102, 31.4%). A total of 85 TC-BSI episodes were recorded (0.36 per 1,000 TC-days). The majority (71, 83.4%) were caused by Gram-positive organisms: Staphylococcus epidermidis (36, 42.4%) and S. aureus (24, 28.0%), including three methicillin-resistant strains. Over 80% of infections occurred after six months of catheter placement. Only four (4.7%) infections occurred within the first 30 days. During follow-up, 177 patients (54.4%) died. The most frequent cause of death was infection (55, 31.1%), although only seven deaths occurred following a TC-BSI (2.1% of the study population).

The implementation of a dedicated protocol for TC implantation was associated with a low incidence of TC-BSI. These infections tended to present late and were predominantly caused by S. epidermidis, a less virulent organism than S. aureus. Among the preventive measures, systematic screening and decolonization of nasal S. aureus carriers significantly reduced the incidence of TC-BSI caused by this pathogen, with no observed increase in methicillin-resistant strains over the long-term follow-up. In our cohort, TC use was associated with low TC-BSI-related mortality and did not negatively impact overall five-year survival. TCs may be a valid and safe option for selected patients in whom arteriovenous fistula creation is not feasible.