Background  Subdural hematoma is the most common type of intracranial hematoma. However, there is no standard treatment for subacute subdural hematoma. Due to its special pathophysiological characteristics, it has potentials to be treated by key-hole endoscopic surgery .

  Objective  To investigate the effect of key-hole endoscopic surgery for subacute subdural hematoma evacuation in emergency situation.

  Methods  From February 2015 to June 2019, 11 patients with subacute subdural hematoma requiring surgery in the First Medical Center and Hainan Hospital of Chinese PLA General Hospital were enrolled in the study. Endoscopic hematoma evacuation was performed through a small bone window posterior to the parietal protuberance with the diameter of 3.0 - 3.5 cm. Hematoma clearance rate, re-bleeding rate, operating time, time of endoscopic procedure and intraoperative blood loss were recorded and analyzed.

  Results  Of the 11 cases of hematoma,10 were on the left side and one was on the right side. There were 6 males and 5 females, with average age of (50.7±18.4) years. The computed tomography analysis revealed that the mean preoperative hematoma volume was (101.02±45.14) mL before surgery, and there was no residual hematoma at day 2 after surgery, representing an average evacuation rate of 100%. The mean preoperative mid-line displacement was (11.45±3.66) mm, and the mid-line displacement reduced to less than (5.15±1.92) mm at 1 day after surgery (P＜0.01). At 1 month after operation, the midline returned to normal. No patient had postoperative re-bleeding. The median time from the incision to the wound close was less than 35 min (range: 30 - 50 min), the median time of endoscopic procedure was 20 min (range: 15 - 30 min), and total blood loss was less than 50 ml. The preoperative Glasgow Coma Scale score was 13.18±2.18, and it improved to 15.00±0 at day 1 after operation (P=0.020).

  Conclusion  Patients in this group has achieved satisfactory results by removing subacute subdural hematoma with key-hole endoscopic surgery, with shorter operating time and less surgical invasion and bleeding.