USE OF THE PEDIATRIC RISK OF MORTALITY SCORE TO PREDICT NOSOCOMIAL INFECTION IN A PEDIATRIC INTENSIVE-CARE UNIT

Objective: To define infection rates in patients with Pediatric Risk of Mortality (PRISM) scores > and < 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 < and > 10. Significantly more infections occurred in the high PRISM population (10.8% vs. 3.4%, p < .001). This association held through age, service, and length of stay. Sensitivity, specificity, positive and negative predictive values of a PRISM score > 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 > 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.