The Nursing Process (NP) is a multi-step, structured framework, that enables nurses to integrate scientific knowledge and optimize patient care. Establishing a Nursing Diagnosis (ND) is a fundamental step of this process, enabling the selection of appropriate interventions. This study presents the development of VIGIL Care, a clinical decision support system designed to enhance NP in intensive care units (ICUs). Using a Delphi method, 13 experts reviewed the 277 nursing diagnoses (NDs) from the latest NANDA-I taxonomy (2024–2026) and selected 32 as relevant for ICU care, and with high criticality or high prevalence. In a second step, a panel of three nursing experts and one internal medicine physician refined the diagnostic indicators associated to the 32 NDs as described in NANDA-I, selecting those deemed highly or moderately relevant. VIGIL Care integrates patient data and employs logical rules to propose patient-specific NDs, while offering an explainable user interface allowing for nursing decisional autonomy preservation. The assessment of 10 NDs across 20 randomly-selected patient cases demonstrated that VlGIL Care achieved 86% sensitivity and 78% specificity, outperforming traditional nursing assessments, especially under time constraints. However, the limited sample size highlights the need for further validation to confirm the system’s effectiveness.