P51. Surgical versus non-surgical management of spinal epidural abscess: long-term outcomes of 250 patients

BACKGROUND CONTEXT Spinal epidural abscess (SEA) is a rare, life-threatening infection within the epidural space with significant associated functional impairment and morbidity. Today, there remains active debate over the role of surgical versus medical management for SEA. The immediate focus of treatment is medical stabilization, clearing the infection, and preserving neurological function. In the long-term, however, little is known about the survival and outcomes comparison between surgical and non-surgical management. PURPOSE This study aims to determine the survivability and long-term outcomes of patients who underwent surgical versus non-surgical management for a SEA. STUDY DESIGN/SETTING Retrospective cohort study conducted at a large tertiary referral center. PATIENT SAMPLE A total of 250 consecutive SEA patients. OUTCOME MEASURES Survival and mortality rates, complications. METHODS All consecutive patients treated at a tertiary medical center for a primary SEA from January 2000 through June 2020 were identified, and data were collected retrospectively through chart review. We included all non-pregnant patients 18 years or older with a SEA and excluded patients with pre-existing spinal hardware and/or prior spine surgery. Descriptive statistics were done for all demographics. Cox proportional hazards regression models were used for all survival analyses while controlling for potential confounding variables. Multiple testing corrections were performed by controlling the false discovery rate. Pre-treatment comorbidities were categorized by the ASA physical status classification system. Non-surgical cases (29.6%, 74/250) were treated by antibiotics and occasionally percutaneous drainage. Surgical cases (70.4%, 176/250) were most commonly treated by decompression (42%, 70/176), decompression with fusion (34%, 57/176), and debridement (18%, 30/176). RESULTS We had a total of 250 patients who met our eligibility criteria. A total of 35 deaths occurred during the study period, for an overall mortality of 14%. More than half of all deaths occurred within the first 90 days after treatment. The 90-day, 3-year, and 5-year posttreatment survival rates were 92.8%, 89.2%, and 86.4%, respectively. Overall mortality among all surgically-treated SEA patients was 13.07%, compared to 16.22% for all medically managed patients. After controlling for potential confounders, surgical treatment (decompression/fusion/debridement) for a SEA significantly reduced the risk of death by 62.4% compared to medical therapy. Additionally, the mean length of stay for surgically-managed SEA patients was significantly longer than that for patients with non-surgical treatment. Risk factors of short-term mortality included hypoalbuminemia (12,000, sepsis, septic shock, ASA 4+, and cardiac arrest.) Compared to medically-managed patients, surgically-treated SEA patients experienced a higher proportion of deep vein thrombosis. CONCLUSIONS The overall long-term survivability of SEA treatment is relatively high (86%) in this study. Our data highlight hypoalbuminemia as a likely risk factor for short-term mortality. For primary SEA patients, surgical management may reduce the mortality risk compared to non-surgical treatment. FDA Device/Drug Status This abstract does not discuss or include any applicable devices or drugs. Spinal epidural abscess (SEA) is a rare, life-threatening infection within the epidural space with significant associated functional impairment and morbidity. Today, there remains active debate over the role of surgical versus medical management for SEA. The immediate focus of treatment is medical stabilization, clearing the infection, and preserving neurological function. In the long-term, however, little is known about the survival and outcomes comparison between surgical and non-surgical management. This study aims to determine the survivability and long-term outcomes of patients who underwent surgical versus non-surgical management for a SEA. Retrospective cohort study conducted at a large tertiary referral center. A total of 250 consecutive SEA patients. Survival and mortality rates, complications. All consecutive patients treated at a tertiary medical center for a primary SEA from January 2000 through June 2020 were identified, and data were collected retrospectively through chart review. We included all non-pregnant patients 18 years or older with a SEA and excluded patients with pre-existing spinal hardware and/or prior spine surgery. Descriptive statistics were done for all demographics. Cox proportional hazards regression models were used for all survival analyses while controlling for potential confounding variables. Multiple testing corrections were performed by controlling the false discovery rate. Pre-treatment comorbidities were categorized by the ASA physical status classification system. Non-surgical cases (29.6%, 74/250) were treated by antibiotics and occasionally percutaneous drainage. Surgical cases (70.4%, 176/250) were most commonly treated by decompression (42%, 70/176), decompression with fusion (34%, 57/176), and debridement (18%, 30/176). We had a total of 250 patients who met our eligibility criteria. A total of 35 deaths occurred during the study period, for an overall mortality of 14%. More than half of all deaths occurred within the first 90 days after treatment. The 90-day, 3-year, and 5-year posttreatment survival rates were 92.8%, 89.2%, and 86.4%, respectively. Overall mortality among all surgically-treated SEA patients was 13.07%, compared to 16.22% for all medically managed patients. After controlling for potential confounders, surgical treatment (decompression/fusion/debridement) for a SEA significantly reduced the risk of death by 62.4% compared to medical therapy. Additionally, the mean length of stay for surgically-managed SEA patients was significantly longer than that for patients with non-surgical treatment. Risk factors of short-term mortality included hypoalbuminemia (12,000, sepsis, septic shock, ASA 4+, and cardiac arrest.) Compared to medically-managed patients, surgically-treated SEA patients experienced a higher proportion of deep vein thrombosis. The overall long-term survivability of SEA treatment is relatively high (86%) in this study. Our data highlight hypoalbuminemia as a likely risk factor for short-term mortality. For primary SEA patients, surgical management may reduce the mortality risk compared to non-surgical treatment.