Time to Initiation of Antibiotic Therapy in Critically Ill Patients with Suspected Sepsis and Its Effect on Intensive Care Unit Mortality: Analysis Using Bayesian Approach

Background and aims: Sepsis is a leading cause of intensive care unit (ICU) admission and mortality.Although early antibiotic therapy in the emergency department improves outcomes, the clinical impact of delays in ICU-based antibiotic escalation is not well established.This study evaluated the association between time to ICU-based initiation of newly prescribed antibiotics and ICU mortality using a Bayesian analytical framework.Patients and methods: A prospective observational study (2019-2021) was conducted in a tertiary care hospital, including adult patients admitted to the ICU.New antibiotic administration represented an escalation of therapy for suspected new-onset or worsening infection.Delay was defined as the interval between prescription and actual administration.Repeated antibiotic escalation events within patients were analyzed using a Bayesian generalized linear mixed model (GLMM) accounting for within-patient correlation.Results: A total of 695 antibiotic escalation events occurred in 467 patients (mean age 50.6 17.7 years; 61.7% male).The majority of patients received antibiotics within 3 hours of sepsis recognition (90.6%), and 42.8% within 1 hour.Intensive care unit mortality was 25.9%.Each hour delay in administration of newly prescribed ICU antibiotics was associated with increased odds of ICU mortality posterior odds ratio (OR): 1.13, 95% credible interval (CrI): 1.11-1.15.Higher mortality was also associated with septic shock, hospital-acquired infection, higher delta sequential organ failure assessment ( SOFA), and higher Acute Physiology and Chronic Health Evaluation (APACHE II) Score.Conclusion: Delays in ICU-based antibiotic escalation are associated with increased mortality.Timely escalation may represent an important, modifiable target to improve outcomes in critically ill patients with suspected sepsis.