65 Neonatal ventilator-associated pneumonia: A tale of three cities in Canada West

Abstract

Abstract Background Preterm infants are at increased risk for acquired infections related to invasive devices such as endotracheal tubes (ETT). Wide heterogeneity exists in diagnostic criteria and management of ventilator-associated pneumonias (VAP), which have not been validated in the neonatal population. Objectives To determine the demographic characteristics and prevalence of VAP according to three different existing criteria used in the neonatal intensive care unit (NICU). Design/Methods In this retrospective study, we included infants born at <33 weeks gestational age from 3 different NICUs in western Canada, who have been diagnosed with VAP during 2018 – 2022. Infants were diagnosed per three diagnostic criteria: (1) Diagnosed per physician diagnoses (mechanically ventilated infants with stability or improvement ≥48 hours and deterioration at the physician’s discretion); (2) VAP diagnostic consensus adopted by some Canadian NICUs (Canadian criteria) (including escalation in respiratory support such as increase in FiO2 by minimum 0.25, increase in MAP by minimum 4 or change in ventilation mode); and (3) Criteria of a paediatric ventilator-associated condition (PVAC) with a positive respiratory diagnostic test (PVAC criteria) (including escalation in respiratory support such as increase in FiO2 by minimum 0.1, increase in MAP by minimum 2 or change in ventilation mode). Results There were 185 neonates diagnosed to have VAP at physicians’ discretion during the study period, with incidences of 4.6%, 8.9%, and 5.7% in the three NICUs. They had a median GA of 25 weeks, a median birth weight of 748-849 grams, and a median onset of VAP ranging from 16-31 days. Among the VAP per physicians’ diagnoses, 18.2-55.0% of infants fulfilled the VAP criteria of Canadian consensus, and 10.9-12.5% of them fulfilled the PVAC criteria with a positive respiratory diagnostic test. The demographic distribution showed similar patterns across the three criteria. Staphylococcus aureus, Enterobacter cloacae complex, Klebsiella species, and oral flora were found to be the most common organisms yielded from ETT aspirate cultures. Conclusion We found that 4.6-8.9% of infants born at <33 weeks GA had VAP diagnosed during their NICU stay. Only around one-ninth of infants fulfilled the PVAC criteria with a positive respiratory diagnostic test. Therefore, there is an urgency to develop neonatal-specific and validated diagnostic criteria for VAP.