[Evacuation of chronic subdural hematomas with the Twist-Drill technique: Results of a randomized prospective study comparing 48-h and 96-h drainage duration]

Abstract

Background and purpose: Technical modalities for the evacuation of chronic subdural hematomas are still controversial. The Twist-Drill technique with closed-system drainage is becoming more widely used, but the influence of drainage duration on outcome has not been studied yet and therefore is still being debated.

Methods: A prospective randomized study was conducted, comparing the results between two drainage durations. Forty-eight hours (Group I; n=35 patients) and 96 h (Group II; n=30 patients).

Results: The two groups had almost identical characteristics due to randomization. The mean volume of liquid drained was 120 ml in the first group and 285 ml in the second, a statistically significant difference. The rate of incomplete evacuation versus the rate of recurrence did not show any significant difference between Group I (5.7 % and 11.4 %, respectively) and Group II (3.3 % and 10 %, respectively). The rate of postoperative complications was 10.7 % in Group I but 26.9 % in Group II, with a respective 3.8 % and 11.4 % mortality rate, proving a statistically significant difference. Clinical improvement observed at discharge was 85.7 % and 84.6 % in Group I and Group II, respectively.

Conclusion: With comparable recurrence and improvement rates, our study demonstrates that it is much more advantageous to remove the catheter at 48 h than leave it in for a longer duration. Not only is bed rest reduced, but the rate of morbidities is also significantly decreased.