Nosocomial infections after cardiac surgery in infants and children: incidence and risk factors

Abstract

This prospective study was undertaken to determine the spectrum, sites and main risk factors for hospital-acquired infections (HAI) in our paediatric cardiothoracic intensive care unit (PCICU), and to determine the main organisms causing bloodstream infection in this setting. All patients admitted between January and December 1999 were prospectively followed for the development of HAI. To define risk factors, patients were grouped by age, complexity score, length of stay in PCICU, and whether the patient's chest was open or closed postoperatively. Three hundred and thirty-five patients underwent cardiac surgery. Fifty-five patients acquired 69 HAIs (HAI patient rate 16.4%). The most common HAI were bloodstream and surgical wound infection in 10 and 8%, respectively. The main causative organisms were Klebsiella spp.,Enterobacter spp. and Pseudomonas spp. in 22, 17 and 16% of episodes, respectively. Staphylococcus spp. accounted for 16% of episodes. The main risk factors for developing HAI were: neonatal age [P < 0.05, odds ratio (OR): 5.89, 95% confidence interval (CI): 2.96-11.58] prolonged PCICU stay (P < 0.05, OR: 6.82, 95% CI: 3.37-14.48), open chest postoperatively (P < 0.05, OR: 3.44, 95% CI: 1.31-8.52) and high complexity score (P < 0.05, OR: 4.03 95% CI: 1.87-8.43). The main causative organisms of bloodstream infections in children hospitalized in the PCICU differ from those in adult and pediatric general intensive care units (ICUs) and include mainly Gram-negative bacilli. High complexity score, neonatal age, prolonged ICU stay, and open chest postoperatively are risk factors of HAI in this patient population.