Tehran University of Medical Sciences Archives of Anesthesiology and Critical Care 2423-5849 0 0 2026 06 16 1561 1561 Ester Ronauli Silaen Department of Anesthesiology and Intensive Care, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. Sri Mahyunita Prof. dr. Chairuddin P. Lubis Universitas Sumatera Utara Hospital, Universitas Sumatera Utara, Medan, Indonesia. Melisa Elva Prof. dr. Chairuddin P. Lubis Universitas Sumatera Utara Hospital, Universitas Sumatera Utara, Medan, Indonesia. 2026 01 31 2026 02 16 Background: Ventilator-associated pneumonia (VAP) represents a major complication in mechanically ventilated ICU patients, driven by poor oral hygiene that promotes oropharyngeal pathogenic colonization. Standardized protocols are essential for effective VAP prevention in nursing care. This study developed and implemented a chlorhexidine-based oral hygiene protocol and evaluated its effectiveness against eucalyptol in reducing VAP risk. Methods: A quasi-experimental nonequivalent control group posttest-only design was conducted in the ICU of Prof. Dr. Chairuddin P. Lubis University Hospital (September 2024). Thirty-two patients underwent purposive sampling and were allocated to intervention (n=16; 0.12% chlorhexidine oral care every shift for 48 hours) or control (n=16; eucalyptol) groups. VAP risk was measured via Clinical Pulmonary Infection Score (CPIS), with bacterial colonization assessed through sputum/bronchoalveolar lavage cultures. Independent t-tests analyzed differences (p < 0.05). Results: The chlorhexidine group had a lower mean CPIS of 2.63 ± 1.31 compared to eucalyptol, which had a mean of 3.25 ± 2.24 (p = 0.032). Acinetobacter baumannii carbapenemase-producers were the most common isolates. Conclusion: The 0.12% chlorhexidine protocol was better than eucalyptol at reducing VAP risk. It should be regularly used in ICU nursing practice. https://aacc.tums.ac.ir/index.php/aacc/article/view/1561