Subperiosteal vs Subdural Drain After Burr-Hole Drainage of Chronic Subdural Hematoma: A Randomized Clinical Trial (cSDH-Drain-Trial)

BACKGROUND: The use of a subdural drain (SDD) after burr-hole drainage of chronic subdural hematoma (cSDH) reduces recurrence at 6 mo. Subperiosteal drains (SPDs) are considered safer, since they are not positioned in direct contact to cortical structures, bridging veins, or hematoma membranes. OBJECTIVE: To investigate whether the recurrence rate after insertion of a SPD is noninferior to the insertion of a more commonly used SDD. METHODS: Multicenter, prospective, randomized, controlled, noninferiority trial analyzing patients undergoing burr-hole drainage for cSDH aged 18 yr and older. After hematoma evacuation, patients were randomly assigned to receive either a SDD (SDD-group) or a SPD (SPD-group). The primary endpoint was recurrence indicating a reoperation within 12 mo, with a noninferiority margin of 3.5%. Secondary outcomes included clinical and radiological outcome, morbidity and mortality rates, and length of stay. RESULTS: Of 220 randomized patients, all were included in the final analysis (120 SPD and 100 SDD). Recurrence rate was lower in the SPD group (8.33%, 95% confidence interval [CI] 4.28-14.72) than in the SDD group (12.00%, 95% CI 6.66-19.73), with the treatment difference (3.67%, 95% CI -12.6-5.3) not meeting predefined noninferiority criteria. The SPD group showed significantly lower rates of surgical infections (P = .0406) and iatrogenic morbidity through drain placement (P = .0184). Length of stay and mortality rates were comparable in both groups. CONCLUSION: Although the noninferiority criteria were not met, SPD insertion led to lower recurrence rates, fewer surgical infections, and lower drain misplacement rates. These findings suggest that SPD may be warranted in routine clinical practice.