Identification of Predictors for Clinical Deterioration in Patients With COVID-19 via Electronic Nursing Records: Retrospective Observational Study

Abstract

Background Few studies have used standardized nursing records with Systematized Nomenclature of Medicine–Clinical Terms (SNOMED CT) to identify predictors of clinical deterioration. Objective This study aims to standardize the nursing documentation records of patients with COVID-19 using SNOMED CT and identify predictive factors of clinical deterioration in patients with COVID-19 via standardized nursing records. Methods In this study, 57,558 nursing statements from 226 patients with COVID-19 were analyzed. Among these, 45,852 statements were from 207 patients in the stable (control) group and 11,706 from 19 patients in the exacerbated (case) group who were transferred to the intensive care unit within 7 days. The data were collected between December 2019 and June 2022. These nursing statements were standardized using the SNOMED CT International Edition released on November 30, 2022. The 260 unique nursing statements that accounted for the top 90% of 57,558 statements were selected as the mapping source and mapped into SNOMED CT concepts based on their meaning by 2 experts with more than 5 years of SNOMED CT mapping experience. To identify the main features of nursing statements associated with the exacerbation of patient condition, random forest algorithms were used, and optimal hyperparameters were selected for nursing problems or outcomes and nursing procedure–related statements. Additionally, logistic regression analysis was conducted to identify features that determine clinical deterioration in patients with COVID-19. Results All nursing statements were semantically mapped to SNOMED CT concepts for “clinical finding,” “situation with explicit context,” and “procedure” hierarchies. The interrater reliability of the mapping results was 87.7%. The most important features calculated by random forest were “oxygen saturation below reference range,” “dyspnea,” “tachypnea,” and “cough” in “clinical finding,” and “oxygen therapy,” “pulse oximetry monitoring,” “temperature taking,” “notification of physician,” and “education about isolation for infection control” in “procedure.” Among these, “dyspnea” and “inadequate food diet” in “clinical finding” increased clinical deterioration risk (dyspnea: odds ratio [OR] 5.99, 95% CI 2.25-20.29; inadequate food diet: OR 10.0, 95% CI 2.71-40.84), and “oxygen therapy” and “notification of physician” in “procedure” also increased the risk of clinical deterioration in patients with COVID-19 (oxygen therapy: OR 1.89, 95% CI 1.25-3.05; notification of physician: OR 1.72, 95% CI 1.02-2.97). Conclusions The study used SNOMED CT to express and standardize nursing statements. Further, it revealed the importance of standardized nursing records as predictive variables for clinical deterioration in patients.