Revisiting the Surgical Outcomes of Non-Acute Subdural Hematomas among Retired Military Personnel : A Single Tertiary Hospital Retrospective Analysis in the Philippines.

Abstract

Objective: Subdural hematomas (SDH) are classified clinically and/or radiologically as acute (ASDH), subacute (SSDH) and chronic (CSDH). The management differ depending on their classification, with only the ASDH having a definite accepted surgical guideline. Non-acute SDH, specifically SSDH and CSDH have no clear surgical guidelines but are managed similarly in some literature. This study was conducted to determine if there is a difference in outcomes among surgically managed non-acute SDH in a specific elderly population of retired military personnel.

Methods: This is a pre-pandemic retrospective study that utilized data obtained from January 2016 to April 2019, in a subspecialty tertiary hospital that caters to retired military personnel or veterans, in the Philippines. After chart review and application of inclusion and exclusion criteria, twenty-one patients were included, all military retirees, with age 56 years old and above. Chart review and electronic database were retrieved to extract relevant information.

Results: In this study, a term 'mixed-type subdural hematoma' (MSDH) was proposed to encompass SDH that have mixed hypo-and-hyperdensity on preoperative CT scan and were subsequently found to have bright red liquefied hematoma instead of the classic engine machinery oil fluid found in a CSDH. Based on the observed cohort, 9 out of 11 CSDH patients attained the Glasgow Outcome Scale Extended (GOS-E) score of 8 while all the respondents in the MSDH group attained the same GOS-E score underscoring the need for early intervention in patients with non-acute subdural hematoma. Moreover, the outcomes of both MSDH and CSDH are comparable with low mortality rate (~9.5%) and immediate postoperative improvement (~90%).

Conclusion: MSDH and CSDH, although classified separately using clinical and/or radiologic means, can collectively be categorized as a non-acute SDH and can be managed safely and effectively with burr hole surgery.