(1234) Ultrashort Versus Short Duration for Hospital-Acquired and Ventilator-Associated Pneumonia (HAP/VAP)

Introduction: Hospital and Ventilator-associated pneumonia (HAP/VAP) is a significant contributor to morbidity and mortality in patients admitted to the intensive care unit (ICU). Appropriate antimicrobial use is paramount to treat infection while minimizing collateral damage. Current guidelines recommend patients diagnosed with HAP/VAP receive a 7-day course of antimicrobial therapy. Some studies indicate a shorter duration in patients with low ventilator settings can be associated with positive results. However additional data is needed in a broader population. This study seeks to compare the outcome of HAP/VAP treatment in patients who receive an ultra-short course of antibiotics.

Methods: This was a retrospective cohort study of patients admitted to University of Kentucky HealthCare Medical ICU from June 5, 2021 to January 1, 2024. The two cohorts were defined by those that received ≤ 5 days of antimicrobials (ultra-short) and those that received > 5 days (short) of antimicrobials for HAP/VAP. The primary study outcome was a composite of recurrence of pneumonia or death within the hospital stay. Secondary outcomes explored factors associated with development of the composite outcome.

Results: A total of 77 patients were included in the final analysis: 28 received a (≤ 5 days) ultra-short course and 49 patients received a (>5 days) short course of antibiotics. There was no significant difference in the primary composite outcome between groups ultra-short 3/28 (10.7%) vs short 10/49 (20.4%), p=0.4. There were significant differences in the day 3 and day 5 P:F ratios in the composite group: day 3 230.0 (130.0- 250.0) vs non-composite group day 3 290.6 (245.0- 351.8), p=0.006. Composite group day 5 P:F was 250.0 (141.4- 342.9) vs non-composite group day 5 330.8 (250.0- 452.4), p=0.039.

Conclusions: This study found no association between antibiotic duration on the composite outcome of recurrence or in hospital morality. There was an association between improvement in hypoxemia indices and development of the composite outcomes, as evidenced by a the more rapid improvement of P:F in the non-composite outcome group. Further analysis should explore the interaction between rapid resolution of hypoxemia and antibiotic duration on VAP/HAP outcomes.