The Richmond Acute Subdural Hematoma Score: A Validated Grading Scale to Predict Postoperative Mortality

Traumatic acute subdural hematomas (aSDHs) are common, life-threatening injuries often requiring emergency surgery.To develop and validate the Richmond acute subdural hematoma (RASH) score to stratify patients by risk of mortality after aSDH evacuation.The 2016 National Trauma Data Bank (NTDB) was queried to identify adult patients with traumatic aSDHs who underwent craniectomy or craniotomy within 4 h of arrival to an emergency department. Multivariate logistic regression modeling identified risk factors independently associated with mortality. The RASH score was developed based on a factor's strength and level of association with mortality. The model was validated using the 2017 NTDB and the area under the receiver operating characteristic curve (AUC).A total of 2516 cases met study criteria. The patients were 69.3% male with a mean age of 55.7 yr and overall mortality rate of 36.4%. Factors associated with mortality included age between 61 and 79 yr (odds ratio [OR] = 2.3, P < .001), age ≥80 yr (OR = 6.3, P < .001), loss of consciousness (OR = 2.3, P < .001), Glasgow Coma Scale score of ≤8 (OR = 2.6, P < .001), unilateral (OR = 2.8, P < .001) or bilateral (OR = 3.9, P < .001) unresponsive pupils, and midline shift >5 mm (OR = 1.7, P < .001). Using these risk factors, the RASH score predicted progressively increasing mortality ranging from 0% to 94% for scores of 0 to 8, respectively (AUC = 0.72). Application of the RASH score to 3091 cases from 2017 resulted in similar accuracy (AUC = 0.74).The RASH score is a simple and validated grading scale that uses easily accessible preoperative factors to predict estimated mortality rates in patients with traumatic aSDHs who undergo surgical evacuation.