Prediction of Delirium Using Admission Inflammatory Biomarkers in Mechanically Ventilated Intensive Care Patients
Predicting Delirium in Ventilated ICU Patients
DOI:
https://doi.org/10.69750/dmls.03.06.0214Keywords:
Delirium, inflammatory biomarkers, intensive care unit, mechanical ventilation, systemic immune-inflammation indexAbstract
Background: Delirium is common among mechanically ventilated intensive care patients, and is linked to longer lengths of hospital and ventilation, and higher death rates. Admission inflammatory biomarkers may allow identification of patients at increased risk.
Objective: To determine the predictive value of admission inflammatory biomarkers for delirium in mechanically ventilated intensive care patients.
Methods: This prospective observational cohort study was conducted in the department of anesthesia and intensive care at the Al-Aleem Medical College, Lahore, Pakistan from January 2025 to January 2026, involving 120 adult patients under invasive mechanical ventilation for more than 24 hours. Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII) and C-reactive protein (CRP) were obtained within 6 hours of admission. Delirium was evaluated twice daily using the CAM-ICU. Receiver operating characteristic analysis and multivariable logistic regression were done.
Results: Delirium occurred in 44 patients (36.7%). Delirium was associated with more inflammation, more severity of illness and more incidences of sepsis. Systemic immune-inflammation index had the highest predictive accuracy with an area under the curve of 0.78. The best cut-off was >2,100 with sensitivity 72.7% and specificity 69.7%. An SIR ≥ 2,100 was an independent predictor of delirium (adjusted odds ratio 3.42; 95% confidence interval 1.49-7.85; p=0.004).
Conclusion: The current study concludes that the systemic immune-inflammation index at admission might be a simple and inexpensive tool for early stratification of delirium risk in critical illness in patients treated with mechanical ventilation.
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