Predictive Factors in Development of Postoperative Delirium in Chronic Subdural Hematomas: A Prospective Multicenter Study

Introduction: Chronic subdural hematoma (CSDH) is a complex disease with an overall incidence of 1.7–20.6 per 100,000 persons per year and is more commonly encountered in the elderly population. It is projected to be one of the most common neurosurgical procedures. Postoperative delirium is a common complication associated with the elderly, causing increased morbidity and prolonged hospital stay. However, its risk factors in chronic subdural hematoma patients have not been well studied. Methods: A total of 202 consecutive patients with chronic subdural hematoma at different neurosurgical centers in Europe between January 2023 and June 2025 were enrolled. Various clinical indicators were analyzed to identify independent risk factors for postoperative delirium using univariate and multivariate regression analyses. Results: Out of the 202 patients (age, 71 (IQR, 18); female-to-male ratio, 1:2.7) studied, 63 (31.2%) experienced postoperative delirium. Univariate analysis identified age (p < 0.001), gender (p = 0.014), restraint belt use (p < 0.001), electrolyte imbalance (p < 0.001), visual analog scale (VAS) pain score (p < 0.001), hematoma thickness (p < 0.001), midline shift (p < 0.001), hematoma side (p = 0.013), hematoma location (p = 0.018), and urinal catheterization (p = 0.028) as significant factors. Multivariate regression analysis confirmed the significance of restraint belt use (B = 7.657, p < 0.001), electrolyte imbalance (B = −3.993, p = 0.001), VAS pain score (B = 2.331, p = 0.016), and midline shift (B = 0.335, p = 0.007). Hematoma thickness and age had no significant impact. Conclusions: Increased midline shift and VAS pain scores, alongside restraint belt use and electrolyte imbalance, elevate delirium risk in chronic subdural hematoma surgery. Our prediction models may offer a reference value in this context.