Impact of anesthesia type on surgical outcomes and medical complications in chronic subdural hematoma surgery

Backgrounds: Chronic Subdural Hematoma (CSDH) is common in elderly patients. Although general anesthesia (GA) has traditionally been used for CSDH surgeries, it may lead to postoperative complications, especially in older patients. We hypothesized that local anesthesia (LA) could reduce postoperative medical complications, including pneumonia, compared to GA.

Methods: We conducted a retrospective study from 2015 to 2019, of medical records of CSDH patients from two hospitals in addition to a comprehensive literature review. Inclusion criteria were a new CSDH diagnoses and treatment with burr-hole craniostomy (BHC) and drain insertion. Patients with recent ipsilateral craniotomies were excluded. Clinical variables included demographics, comorbidities, hematoma characteristics, and post-operative outcomes.

Results: Of 383 eligible patients, 63 underwent BHC under LA (LA group), and 320 under GA (GA group). Both groups exhibited similar baseline characteristics, hematoma characteristics, and surgical outcomes, including postoperative CT findings and ICU stay duration. There was also no significant difference in postoperative bleeding events between the groups. Although patients in the GA group experienced a higher incidence of postoperative pneumonia (3.8 % vs 1.6 %), multivariate analysis revealed that the occurrence of pneumonia was associated with a history of lung disease and preoperative neurological status (OR 7.28, p = 0.018, OR 3.40, p < 0.001, respectively) rather than with the type of anesthesia used.

Conclusion: Our study suggests that the type of anesthesia does not influence postoperative surgical and medical outcomes, including pneumonia, which is the most common medical complication of BHC for CSDH. Rather, preoperative neurological status and underlying morbidities appear to be more closely related to postoperative medical complications. Future large, prospective studies are needed to validate our findings.