Background: Chronic subdural hematoma (cSDH) is a common neurosurgical condition responsible for excess morbidity, particularly in the geriatric population. Recovery after evacuation is complicated by fluctuating neurological deficits in a high proportion of patients. We previously demonstrated that spreading depolarizations (SD) may be responsible for some of these events. In this study, we aim to determine candidate risk factors for probable SD and assess the influence of probable SD on outcome.
Methods:We used two cohorts who underwent surgery for cSDH. The first cohort (n=40) had electrocorticographic (ECoG) monitoring to detect SD. In the second cohort (n=345), we retrospectively identified subjects who, based on neurological exam changes without clear structural cause in the absence of seizure activity on EEG, we suspect had probable SD. We extracted standard demographic and outcome variables for comparisons and modeling.
Results: 80/345 (23%) of subjects were identified in the retrospective cohort as having probable SD. Potential risk factors included history of hypertension, worse clinical presentation on GCS (Glasgow coma scale score), and surprisingly, lower Hounsfield Unit density and volume of SDH. Probable SD was associated with multiple worse outcome measures including length of stay and clinical outcomes, but not increased mortality. On multivariable analysis, probable SD was independently associated with worse outcome determined by Glasgow outcome scale at first clinic follow up (OR=1.793, 95%CI 1.022-3.146), and longer hospital length of stay (OR=7.952, 95%CI= 4.062-15.563).
Conclusions: Unexplained neurological deficits after surgery for cSDH occur in nearly a quarter of patients and may be explained by SD. Patients with probable SD have worse outcomes, independent of other baseline risk factors. Further data with gold standard monitoring is needed to evaluate for possible predictors of SD in order to target therapies to a high-risk population.
Medows, Christine; Herbert Davis; Laila Mohammad; C William Shuttleworth; Michel Torbey; Yiliang Zhu; Ali A. Alsahara; and Andrew P. Carlson. "Spreading Depolarization After Chronic Subdural Hematoma Evacuation: Associated Clinical Risk Factors and Influence on Clinical Outcome." (2021). https://digitalrepository.unm.edu/hsc-bbhrd/2