Objective: To define infection rates in patients with Pediatric Risk of Mortality (PRISM) scores greater than and less than 10 on admission to the pediatric ICU (PICU).
Design: Descriptive.
Setting: An 18-bed PICU admitting patients of all ages except nonsurgical neonates; within a 585-bed tertiary care pediatric hospital.
Patients: Patients admitted to the PICU from July 1987 to February 1988 inclusive. Of 685 admitted, 480 were followed for greater than or equal to 72 hr.
Methods: The baseline state of the patients on admission was determined by a designated intensivist using the PRISM score. Other variables included age, length of stay, and hospital day of onset of infection. Infections were identified by a designated intensivist who undertook prospective daily bedside observation, chart, radiographic, and laboratory review.
Measurements and main results: Equal portions of patients had PRISM scores less than and greater than 10. Significantly more infections occurred in the high PRISM population (10.8% vs. 3.4%, p less than .001). This association held through age, service, and length of stay. Sensitivity, specificity, positive and negative predictive values of a PRISM score greater than 10 were 75%, 53%, 11%, and 97%, respectively. Bacteremias accounted for 36% of infections, skin/eye/drain site 22%, respiratory 16%, wound 15%, and urine 9%. The most prevalent organisms were coagulase-negative staphylococci (32%), Pseudomonas aeruginosa (23%), Candida sp. (20%), and S. aureus (9%).
Conclusions: A PRISM score greater than 10 on PICU admission characterizes a population within the PICU at increased risk of infection. However, 93% of patients did not develop infection and thus, a negative predictive value of 97% yields little additional information.