This is a descriptive cohort study that retrospectively reviewed the patients who underwent CSDH evacuation in Ain Shams University hospitals from October 2007 to August 2017. An approval from the research ethics committee of the Faculty of Medicine at Ain Shams University (reference number: FWA 00006444) was obtained. Furthermore, being a retrospective study, patients’ consents for participation and for publication were not applicable.
The study included adult patients (≥ 18 years) who underwent burr-hole evacuation of a unilateral CSDH and inner membrane opening.
Patients included in the study either had a normal coagulation profile or a defect that could be properly corrected prior to surgery. On the other hand, patients with bleeding tendencies that failed to be corrected prior to surgery were excluded from the current study.
The clinical data were collected from the patients’ charts and included the following: patients’ demographics, the apparent cause of the subdural hematoma, preoperative clinical state, laboratory findings, preoperative brain computed tomography (CT) scan findings, operative details, postoperative course and management of any complications, recollection of CSDH, follow-up CT scan findings, and the progressive notes in the follow-up visits.
CT scan appearance of the hematoma was classified into hypodense and isodense according to the brain parenchyma or a mixed density including hyperdense areas.
The preoperative and postoperative neurological status was classified according to the Markwalder’s Neurological Grading System [19].
In addition, assessment of the patients’ motor functions was documented according to the Medical Research Council (MRC) grading system [20]. However, for statistical purposes, only the most severely affected muscle group was considered as a representative of muscle power.
All the patients received prophylactic antiepileptic in the form of phenytoin (loading and maintenance doses) except in known hepatic patients, levetiracetam was used instead. Antiepileptic medications were continued for 6 months and then gradually withdrawn unless seizures occurred, in which case the antiepileptics were continued for 1 year after the last seizure.
Prophylactic intravenous antibiotics were administered 1 h prior to induction of anesthesia and continued for 72 h postoperatively followed by 5 days of oral antibiotic use.
Patients with preoperative thrombocytopenia < 100,000/μl received a platelet transfusion to increase the platelet count to ≥ 100,000/μl. Furthermore, antiplatelets were stopped on admission and restarted 4 weeks after surgery unless otherwise indicated. In such instance, patients received platelet transfusion intraoperatively even if their bleeding and clotting times were normal. Anemic patients received packed RBC transfusion to raise the hemoglobin to ≥ 10 g/dl.
Patients with preoperative prolonged prothrombin time (whether due to anticoagulant therapy or due to an intrinsic pathological coagulation defect) received fresh frozen plasma (FFP) to correct the international normalized ratio (INR) to ≤ 1.4.
All surgeries were done under general anesthesia with one or two coin-sized (about 2 cm in diameter) burr holes performed and located according to the operating surgeon’s decision based on the size and configuration of the hematoma.
The dura was coagulated by bipolar diathermy and then was incised in a cruciate fashion along with the outer membrane of the subdural hematoma, and then, the dural edges were coagulated, followed by gentle washing of the hematoma cavity by warm normal saline till the wash became clear.
In at least in a single burr hole in each patient, the inner membrane was identified (Fig. 1), coagulated, and gently opened wide enough to allow evacuation and irrigation of the underlying contents which were lighter in color than the subdural fluid proper. In a few instances, an operating microscope was used for better visualization. The underlying arachnoid was left intact.
The subdural space was then filled with saline to wash out the subdural air. A suction drain catheter was placed over each burr hole letting the terminal end of the catheter in the subgaleal space. The catheter was pulled through a separate skin incision and sutured to the skin, then connected to its collecting chamber after compressing it to about 25% of its height to create a low negative pressure in the closed system for continuous drainage. No subdural catheter was used in any case. Wound closure was performed using full thickness interrupted sutures.
Postoperatively, patients remained flat on the bed for 2 days. The drain was removed 48–72 h after surgery.
After discharge from the hospital, follow-up visits were once every 2 weeks for 2 months and then once monthly afterward.
Follow-up brain CT was done on the 5th postoperative day, 2 weeks after discharge, and upon any reappearance of preoperative symptoms.
The recurrence rate was defined as the reappearance of symptomatic ipsilateral subdural reaccumulation with mass effect within 3 months after surgery.
Statistical analysis
Collected data were expressed as mean ± standard deviation and range and compared via a paired Student’s t test using SOFA statistics version 1.3.3 software.
