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Published on: September 21, 2015
Stanford study of the validity of the pre-interventional preventive risk assessment (PIPRA) tool for at-risk elderly
Matthew Gunther1, Derek Pipolo1, Shixie Jiang2
1Stanford University, School of Medicine, Department of Psychiatry and Behavioral Sciences, 401 Quarry Road, #2317, Stanford, CA 94305, United States of America.
Introduction:
Post-operative delirium (POD) is a frequent complication in older adults following surgery, leading to higher morbidity and mortality. This study evaluates the validity of the Pre-Interventional Preventive Risk Assessment (PIPRA) tool in predicting POD in an elderly orthopedic population.
Methods:
We enrolled 250 patients aged 65 or over undergoing elective orthopedic surgery (knee or hip arthroplasties). Delirium was assessed using the Confusion Assessment Method (CAM) and additional DSM-5 based neuropsychiatric evaluations. The PIPRA tool was applied retroactively to generate delirium risk scores based on nine validated risk factors found within the patient's electronic medical record (EMR).
Results:
Of 241 patients, 13 (5.4 %) developed POD. The median PIPRA score for delirious patients was significantly higher (24.3) compared to non-delirious patients (8.95). Logistic regression identified age (OR = 1.12) and history of cognitive impairment (OR = 10.38) as significant predictors of POD. The PIPRA tool demonstrated an area under the curve (AUC) of 0.748.
Discussion:
Our study supports PIPRA's validity in assessing delirium risk using readily available clinical parameters from patients' EMRs. When integrated into clinical workflows, this model can preoperatively stratify delirium risk, enabling targeted interventions to prevent its onset.
Conclusion:
The PIPRA tool presents an innovative approach to evaluating POD risk in surgical populations. By identifying at-risk patients, PIPRA can facilitate informed consent discussions and the implementation of effective preventive measures. Future research should validate its performance across diverse surgical cohorts to refine predictive capabilities and optimize delirium prevention strategies.
