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A nomogram for predicting sedation-related adverse events in elderly patients undergoing painless gastrointestinal
Liu Xu1, Qiyuan Yin1, Hui Liu1
1Department of Anesthesiology, Wenjiang Hospital of Sichuan Provincial People's Hospital, Chengdu Wenjiang District People's Hospital, Chengdu, China.
Background:
Elderly patients undergoing painless gastrointestinal endoscopy are at increased risk for sedation-related adverse events (SRAEs) because of their greater physiological vulnerability and higher likelihood of comorbidities. Risk stratification before endoscopy may improve perioperative safety and individualize sedation and management.
Objective:
This study aimed to develop and internally validate a Firth-penalized multivariable logistic regression model and nomogram to predict SRAEs in elderly patients undergoing painless gastrointestinal endoscopy.
Methods:
Prospective data from 520 patients at least 60 years old who underwent painless gastrointestinal endoscopy between April 2023 and June 2024 at our medical center were randomly divided into a training set (n = 364) and validation set (n = 156). SRAEs were defined as intraoperative hypotension or hypoxemia, and independent predictors of SRAEs in the training set were identified through Firth's penalized multivariable logistic regression. A nomogram to predict risk of SRAEs was developed using R software and tested against the validation set. Its performance was assessed in terms of receiver operating characteristic curves, calibration plots, and decision curve analysis.
Results:
In the training set, hypotension and hypoxemia occurred in 39.0 and 33.5% of patients, respectively, the incidence of SRAEs was 45.6%. The independent predictors were older age, history of snoring, frailty, preexisting hypertension, chronic obstructive pulmonary disease, prolonged fasting before the procedure, and higher initial dose of etomidate-propofol. Conversely, regular physical activity was a protective factor. The nomogram built from the training set discriminated between people in the validation set who experienced SRAEs or not with an area under the curve of 0.92 (95% CI, 0.86-0.97), it showed good calibration in the Hosmer-Lemeshow test (P = 0.63), and decision curve analysis demonstrated clinical utility across a wide range of threshold probabilities (7-93%).
Conclusion:
A predictive model based on readily available clinical variables can accurately estimate SRAE risk in elderly patients undergoing painless gastrointestinal endoscopy. The model may be useful for individualizing sedation and patient management.
Clinical Trial Registration:
https://www.chictr.org.cn/showproj.html?proj=188331, identifier ChiCTR2300069816.
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