Spinal epidural hematoma and abscess after neuraxial anesthesia: a historical cohort study using the Japanese Diagnosis Procedure Combination database.

BACKGROUND: Spinal epidural hematoma and abscess are rare complications of neuraxial anesthesia but can cause severe neurologic deficits. The incidence of these complications vary widely in existing studies and the risk factors remain uncertain. We estimated the incidence of these complications and explored associations using a national inpatient database in Japan.

METHODS: Using Japanese Diagnosis Procedure Combination data on surgical inpatients who underwent neuraxial anesthesia from July 2010 to March 2017, we identified patients with spinal epidural hematoma and/or abscess. We investigated age, sex, Charlson comorbidity index, antithrombotic therapy, type of surgery, admission, and hospital for association with these complications. The incidences of spinal epidural hematoma and abscess were estimated separately, and a nested case-control study was performed to examine factors associated with these complications.

RESULTS: We identified 139 patients with spinal epidural hematoma and/or abscess among 3,833,620 surgical patients undergoing neuraxial anesthesia. The incidences of spinal epidural hematoma and abscess were 27 (95% confidence interval [CI], 22 to 32) and 10 (7 to 13) per one million patients, respectively. Spinal anesthesia was associated with significantly fewer complications compared with epidural or combined spinal epidural anesthesia (odds ratio, 0.15; 95% CI, 0.08 to 0.32). Antiplatelet agent (odds ratio, 0.49; 95% CI, 0.06 to 3.91) and anticoagulants (odds ratio, 1.65; 95% CI, 0.95 to 2.85) were not significantly associated with these complications.

CONCLUSIONS: This analysis identified the incidences of spinal epidural hematoma and/or abscess after neuraxial anesthesia. Additional large-scale studies are warranted to examine the incidences and factors associated with these complications.