RESUMO
Objective:To develop and validate a predictive model for post-anesthesia care unit (PACU) hypotension in elderly patients undergoing painless gastrointestinal endoscopy.Methods:The medical records of elderly patients of both sexes, aged ≥60 yr, of American Society of Anesthesiologists Physical Status classification Ⅰ-Ⅲ, undergoing painless gastrointestinal endoscopy at the Endoscopy Center of Subei People′s Hospital from March to June 2021, were retrospectively collected. The patients were randomly divided into training and validation sets according to the ratio of 3∶1. In the training set, the characteristic variables associated with PACU hypotension were screened by Lasso regression, and the independent risk factors for PACU hypotension were identified by multivariate logistic regression analysis of the characteristic variables, according to which a nomogram model predicting the risk for PACU hypotension was established.The discrimination, calibration and accuracy of the model were evaluated by calibration curve and receiver operating characteristic(ROC)curve. And the clinical practicability of the model was determined by decision curve analysis and further assessed by external validation.Results:Of the 973 patients ultimately included, 378 patients experienced PACU hypotension, with an incidence of 38.8%. Multivariate logistic regression analysis showed that age, prolonged preoperative water deprivation time, increased percentage of changes in SBP before and after induction, and intraoperative MAP <65 mmHg were independent risk factors for hypotension in the PACU, and intraoperative use of norepinephrine was a protective factor. The nomogram model was then developed based on the results. The area under the ROC curve was 0.710 (95% confidence interval [ CI] 0.672-0.748) in training set and 0.778 (95% CI 0.720-0.837) in validation set. In training and validation sets, the calibration curves were tested by Hosmer-Lemeshow good of fit test, the P values were 0.590 and 0.950, respectively. The decision curve analysis curve showed that the risk threshold of the prediction model in the training and validation sets were between 20% and 82% and between 18% and 92%, respectively, in the external validation. Conclusions:The nomogram model for prediction of PACU hypotension is successfully established based on age, prolonged preoperative water deprivation, percentage of change in SBP before and after induction, intraoperative MAP <65 mmHg and use of norepinephrine in elderly patients undergoing painless gastrointestinal endoscopy, and the model can visually and individually predict the risk of PACU hypotension.