Surgery After Primary Dexamethasone Treatment for Patients with Chronic Subdural Hematoma-A Retrospective Study

BACKGROUND: We aimed to quantify the need for additional surgery in patients with chronic subdural hematoma (CSDH) primarily treated with dexamethasone and to identify patient characteristics associated with additional surgery. METHODS: Data were retrospectively collected from 283 patients with CSDH, primarily treated with dexamethasone, in 3 hospitals from 2008 to 2018. Primary outcome was the need for additional surgery. The association between baseline characteristics and additional surgery was analyzed with univariable and multivariable logistic regression analysis and presented as adjusted odds ratios (aOR). RESULTS: In total, 283 patients with CSDH were included: 146 patients (51.6%) received 1 dexamethasone course (DXM group), 30 patients (10.6%) received 2 dexamethasone courses (DXM-DXM group), and 107 patients (37.8%) received additional surgery (DXM-SURG group). Patients who underwent surgery more often had a Mark-walder Grading Scale of 2 (as compared with 1, aOR 2.05; 95% confidence interval [CI] 0.90-4.65), used statins (aOR 2.09; 95% CI 1.01-4.33), had a larger midline shift (aOR 1.10 per mm; 95% CI 1.01-1.21) and had larger hematoma thickness (aOR 1.16 per mm; 95% CI 1.09-1.23), had a bilateral hematoma (aOR 1.85; 95% CI 0.90-3.79), and had a separated hematoma (as compared with homogeneous, aOR 1.77; 95% CI 0.72-4.38). Antithrombotics (aOR 0.45; 95% CI 0.21-0.95) and trabecular hematoma (as compared with homogeneous, aOR 0.31; 95% CI 0.12-0.77) were associated with a lower likelihood of surgery. CONCLUSIONS: More than one-third of patients with CSDH primarily treated with dexamethasone received additional surgery. These patients were more severely affected amongst others with larger hematomas.