Bacteremia associadas a cateteres vasculares centrais: etiologia, patogênese e fatores de risco em uma UTI de adultos clínico-cirúrgica de um hospital universitário brasileiro

Abstract

Bloodstream infection (BSI) associated and related to Central Venous Catheter (CVC) resulted in increasing rates of morbidity, mortality and hospital costs. The aim of this study was to investigate the incidence, etiopathogenesis and risk factors related to BSI associated and related to CVC, in a assorted adults Intensive Care Unit (ICU). A longitudinal study of patients using CVC, and case (patients with bacteremia) versus control (patients without infection) of adults in the ICU was carried in Hospital das Clínicas of the Federal University of the Uberlândia, from April 2007 to march 2008 by the NNIS system ( National Nosocomial Infection Surveillance ). Samples from nasal, hub, and insertion site of the catheter were made with swab and cultures on blood agar, MacConkey, Salt Mannitol and Sabouraud. The microorganisms from blood were recovered in the microbiology laboratory of the hospital and the tips of CVC, analyzed by quantitative technique. We evaluated 502 patients admitted to the ICU, of which 435 were using CVC, with 11.2% developing BSI and only tree related to catheter, with an incidence rate of primary bacteremia of 9.5 per 1000 CVC days. The incidence rate of sepsis was 21.3%, with the acquired in hospital accounting for 61.9% of the total, and the acquired in the community was 30.9%. The frequencies of total mortality of these patients were 9.3%, 40.5% and 54.5% in those patients with clinical sepsis, severe sepsis and septic shock, respectively, the majority of deaths (60.6%), during the period of investigation, related to hospital sepsis The investigation of the origin of this microorganisms causing this bacteremias, including those defined as asymptomatic infections (N=17) showed no relation with the hub and skin. The significant risk factors, by univariate analysis, for all bacteremia, including primary (N=34) and secondary (N=15) were: use CVC ≥ 15 days, parenteral nutrition, use ≥ 2 antibiotics and nasal colonization by S. aureus. The independent risk factors for the development of bacteremia included the use of ≥ 2 ATB and Parenteral Nutrition. The coagulase-negative Staphylococci was the most common microorganism causing BSI related to CVC (52.9%). The incidence of bacteremia was right (11.2%), most primary (69.0%) associated with CVC, with the coagulasenegative Staphylococci as the main casual agent.