Objective: To evaluate the risk factors that influence time to acquisition of a laboratory-confirmed bloodstream infection (LCBI).
Design: Prospective cohort study with an 18-month follow-up.
Setting: A 16-bed medical and/or surgical pediatric intensive care unit that cares for patients of the Brazilian Public Health System exclusively.
Patients: We included children from 0 to 18 years old who were represented by 875 consecutive admissions to the pediatric intensive care unit from January 1, 2005, through June 30, 2006. The children from all but 5 (0.6%) of the admissions were followed up until discharge or death. The majority (506 [58.2%]) were hospitalized for surgical pathology, and 254 (29.2%) underwent heart surgery.
Methods: We used a standardized questionnaire and data collection from daily charts. Information on risk factors was collected before the onset of first LCBI. Survival analysis was performed using the Kaplan-Meier method. The effect of the variables on the risk of LCBI each day was estimated through a Cox model fitting.
Results: Fifty-seven children (6.6%) developed an LCBI, 54 (94.7%) of whom made use of a central venous catheter. LCBI incidence was 11.27 episodes/1,000 patient-days and 17.92 episodes/1,000 patient-days when associated with a central venous catheter. Factors associated with time to the first LCBI in the Cox model were age less than 2 years (hazard ratio [HR], 1.99; 95% confidence interval [CI], 1.02-3.89), malnutrition (HR, 1.74; 95% CI, 1.01-3.00), use of a central venous catheter (HR, 4.36; 95% CI, 1.30-14.64), use of antibiotics before admission (HR, 0.58; 95% CI, 0.33-0.98), and use of transfused blood products (HR, 0.40; 95% CI, 0.22-0.74).
Conclusion: Factors associated with time to acquisition of LCBI were age less than 2 years, weight-for-age z score less than -2, and the use of a central venous catheter. Therefore, intensification of LCBI prevention efforts in patients with these characteristics is fundamental.