Evaluation of the Corrected Carotid Flow Time and The Inferior Vena Cava Collapsibility Index in Predicting Post-Spinal Anesthesia Hypotension in Geriatric Patients

Background:Post-spinal anesthesia hypotension (PSAH) is a frequent and potentially dangerous complication, especially in geriatric patients who are more susceptible due to age-related physiological changes and comorbidities. Accurate, non-invasive predictors of PSAH are essential to minimize risks and guide fluid management. Two emerging tools, corrected carotid flow time (CFTc) and inferior vena cava collapsibility index (IVCCI), offer real-time ultrasound-based assessment of intravascular volume and fluid responsiveness.
Objective: We aimedto compare the efficacy of the ultrasonographic assessment of the CFTc with that of the IVCCI in predicting PSAH in geriatric patients.
Patients and Methods: This prospective observational study was conducted at Fayoum University Hospital on 282 geriatric patients who underwent elective surgeries. Before spinal anesthesia, patients were positioned supine with their head tilted to the opposite side of the operator. Ultrasound measurements of CFTc were obtained using a high-frequency linear probe while IVCCI was assessed with a low-frequency curvilinear probe. The primary outcome was the receiver operating characteristic (ROC) curve for CFTc and IVCCI values in predicting PSAH in geriatric patients.
Results: The incidence of PSAH among patients was 16.3%. The mean CFTc was 300.34 ± 19.65 msec, and the mean IVCCI was 27.89 ± 5.87%. According to ROC curve analysis, CFTc and IVC collapsibility index were not significant predictors of PSAH, with AUCs of 0.506 (95% CI: 0.446 to 0.566 and p-value: 0.902) and 0.515 (95% CI: 0.455 to 0.574 and p-value: 0.737), respectively. Conclusion: Neither CFTc nor IVCCI can be used independently as reliable predictors of PSAH in geriatric patients. Their role in predicting PSAH in the elderly appears limited and further research is needed to explore more comprehensive predictive tools for PSAH in this age group.