Structuring for Patient Safety: SNOMED CT–based Standardized Terminology Mapping of ICU Nursing Records

Purpose: This study aimed to identify patient safety concepts from nursing records in intensive care units (ICUs) and to explore their semantic structure through mapping to Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT).Methods: Nursing records from ICUs in five hospitals were reviewed to extract patient safety concepts and related nursing terms. The extracted terms were mapped to SNOMED CT (January 2025 international release), and mapping types and top-level hierarchies were analyzed to identify the structural characteristics of patient safety concepts within the nursing records.Results: From a total of 19,511 nursing terms, five patient safety concepts—pressure injury, falls, medication, infection, and respiration—were derived, and 1,096 nursing terms were mapped. Respiration (368, 33.6%) and infection (283, 25.8%) accounted for the largest proportions, reflecting the frequent interventions related to mechanical ventilation and invasive devices in ICUs. Most of the mapped terms belonged to the Procedure hierarchy (868, 79.2%), indicating that ICU nursing records are primarily focused on assessments and interventions performed by healthcare providers. Clinical findings (175, 16.0%) were relatively fewer but played an important role in safety monitoring by documenting patient status changes and negative observations such as “no apnea” or “no adverse drug reaction.” Broad matches were the most frequent mapping type, with 579 cases (52.7%), indicating that nursing records reflect the detailed and context-specific expressions used in actual clinical practice. Only 20 terms (1.9%) were classified as No matches, mainly in the infection and respiration domains.Conclusion: The findings of this study demonstrate that by deriving patient safety concepts from ICU nursing records and standardizing the corresponding nursing terms with SNOMED CT, nursing records can serve as a key resource for establishing patient safety management systems.