Nurse-Led Implementation of the ABCDEF Bundle

The study employed a single-center, quasi-experimental clinical design with two parallel groups: an intervention group that received the nurse-led ABCDEF bundle and a control group that received standard ICU care. No randomization was applied, but baseline characteristics were matched where possible to control for confounding variables.

The study was conducted in the adult ICU of a tertiary care hospital. Eligible participants included adult patients (≥18 years) who were admitted to the ICU with an expected stay of at least 48 hours. Patients with pre-existing cognitive impairment, severe neurological damage, or those in a persistent vegetative state were excluded.

The intervention group received structured nursing care guided by the ABCDEF bundle, delivered by trained ICU nurses. The protocol included routine pain assessments and management strategies; daily spontaneous awakening and breathing trials; evidence-based sedation choices minimizing benzodiazepine use; systematic delirium screening using a validated tool (e.g., ICDSC); early mobilization practices appropriate to the patient's clinical status; and inclusion of family members in care planning and education.

The control group received usual ICU care without the formal implementation of the ABCDEF bundle.

The primary outcome was the incidence of delirium during the ICU stay, measured using a validated tool (e.g., ICDSC or CAM-ICU). Secondary outcomes included agitation levels, duration of delirium episodes, ICU length of stay, adherence to individual ABCDEF components, use of physical restraints, and sedative/analgesic dosages.

Data were collected prospectively from patient medical records, bedside observations, and standardized assessment tools. Daily monitoring was conducted to ensure fidelity to the intervention and accurate documentation of outcomes.

Ethical approval was obtained from the institutional review board. Written informed consent was obtained from patients or their legal representatives where applicable.

Inclusion criteria

• Critically ill adult patients aged 18 years or older
• Admitted to the ICU at Ain Shams University Hospitals within 48 hours of enrollment
• Clinically stable to undergo assessment and nursing intervention
• Able to provide informed consent personally or via a legally authorized representative
• Both male and female patients included

Exclusion criteria

• Documented cognitive impairment or pre-existing psychiatric illness
• Severe neurological conditions (e.g., advanced stroke, traumatic brain injury)
• Deep sedation level (Richmond Agitation-Sedation Scale [RASS] score < -4)
• Terminal illness requiring palliative or end-of-life care
• Patients who declined participation or did not meet eligibility screening