Exhaustive Drainage Versus Fixed-time Drainage for Chronic Subdural Hematoma After One-burr Hole Craniostomy

All participants are treated with burr-hole craniotomy and a drainage system as follows. Participants undergo surgical procedure under local anesthesia in the hemisphere with a lateral position, but general anesthesia is performed when participant cannot tolerate the operation. A single 1.5 cm burr hole is drilled over the maximum width of the hematoma cavity. After coagulating with bipolar diathermy, dura mater is opened with a cruciate incision. A soft catheter is placed carefully in all directions of the hematoma cavity for irrigating subdural collections with 1,000 mL warm Ringer's lactate saline until clarification. The drainage catheter is inserted ½ length of the maximum diameter of the hematoma cavity toward the frontal region. After the skin is closed, the catheter was connected to a soft collection bag that is placed under the head for passive drainage. During the drainage period, participants stay in bed until the drain is removed.

All participants will be treated with a one-burr-hole craniotomy with irrigation and a closed drainage system. The drainage will be removed after 48 hours.

All participants will be treated with a one-burr-hole craniotomy with irrigation and a closed drainage system. If the computed tomography (CT) scan on the first day after surgery indicates that the affected brain region shows sufficient re-expansion, the drainage catheter will be removed when drainage ceases. If subdural collections remain in the hematoma cavity, the participant will be treated with 30,000 U urokinase injection into the hematoma cavity through the catheter. The catheter will be closed and reopened in 1.5-2 hours, and a CT scan will be performed when drainage ceases. If the CT scan shows sufficient re-expansion of the brain, the catheter will be removed. However, if the brain does not show good re-expansion and there is still a residual subdural collection, the above steps will be repeated. If the participant is subjected to urokinase injection for 3 times, the catheter will be removed when drainage ceases.

All participants undergo a CT scan before the drain is removed, and the last CT scan will be performed before the patient is discharged from the hospital.