ABCDEF Bundle Implementation for ICU Delirium Prevention and Sedation Optimisation: A Twelve-Month Prospective Cohort and Quality Improvement Programme: Bundle Compliance, Delirium-Free Days, and Functional Outcomes in Three Hundred and Twenty-Four Adult ICU Patients

ICU delirium affects 60-80% of mechanically ventilated patients and is an independent predictor of prolonged mechanical ventilation, ICU and hospital length of stay, mortality, and long-term cognitive impairment. The ABCDEF bundle Assess, prevent and manage pain; Both spontaneous awakening and breathing trials, Choice of analgesia and sedation, Delirium monitor, prevent, and manage, Early mobility, Family engagement integrates evidence-based interventions into a structured daily workflow. We undertook a 12-month prospective cohort study with embedded quality improvement programme involving 324 consecutive ICU patients with an expected stay of at least 48 hours. Delirium incidence at any point during ICU admission was 52.5% by CAM-ICU. Composite ABCDEF compliance (all six elements achieved on a given ICU day) rose from 28% at programme launch to 82% by month 12 through iterative QI cycles. Delirium-free and coma-free days at day 14 differed substantially by compliance: 9.2 days with full bundle compliance, 6.4 days with partial compliance, and 3.6 days with non-compliance. Strongest independent predictors of new-onset delirium included deep sedation, benzodiazepine exposure, ABCDEF non-compliance, mechanical ventilation, untreated pain, pre-ICU cognitive impairment, sepsis, and elderly age. Bundle compliance and early mobilisation were strongly protective.

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