Assessment of the Clinical Pulmonary Infection Scores for prediction of ventilator associated pneumonia in patients with out of hospital cardiac arrest.

BACKGROUND: Patients suffering out-of-hospital cardiac arrest (OHCA) are at an increased risk of aspiration pneumonitis and development of subsequent aspiration pneumonia. The diagnostic uncertainty in this context can lead to a large proportion receiving broad spectrum antibiotics. METHODS: This was a three-year, retrospective cohort study of consecutive patients admitted with OHCA. Data were collected in an Australian tertiary centre intensive care unit (ICU) between December 2016-December 2019. We assessed the incidence of Ventilator associated pneumonia (VAP), admission Clinical Pulmonary Infection Scores (CPIS) in patients with OHCA and its' association with VAP at day 3 [1]. We also assessed antibiotics prescribing (timing of initiation and drug choice) and intensive care mortality relative to the day 1 CPIS. RESULTS: Over the three years, 100 patients were admitted with OHCA. The incidence of VAP was 6%. The CPIS on admission was not associated with development of VAP at day 3 (p = 0.75) and no significant association was found between choice of antibiotic regimens and VAP incidence. Timing of initiation of antibiotics was associated with VAP (12hrs vs 48hrs, p = 0.035) but not the choice of antibiotic (penicillin and cephalosporins vs antipseudomonal antibiotics). CPIS score at day 1 was not associated with ICU mortality in a multivariate analysis. CONCLUSION: We demonstrated a very low incidence of VAP in OHCA patients in comparison to published studies. In this context, there was no evidence for an association between CPIS score and VAP at day 3. The CPIS may have utility as a decision support tool for targeted antibiotic prescribing in this cohort.