P33. Complication rates following Chiari malformation surgical management for Arnold-Chiari type I based on surgical variables: a national perspective

BACKGROUND CONTEXT Chiari malformations (CM) are congenital or acquired hind brain anomalies with resultant cerebellar tonsillar herniation through the foramen magnum. Chiari I malformation consists of herniation of the cerebellar tonsils into the foramen magnum thus crowding the craniocervcial junction. Surgical management is variable among these type 1 patients(pts) based on their presenting symptoms. PURPOSE Identify complication rates following CM surgery. STUDY DESIGN/SETTING Retrospective cohort study of (Kids’ Inpatient Database) KID. PATIENT SAMPLE Chiari Malformation Type I. OUTCOME MEASURES Complication rates, fusion, decompression, duroplasty, laminectomy, LOS, Readmission. METHODS The KID database was queried for diagnoses of operative Chiari Malformation from 2003-2012 by ICD-9 codes (348.4). Differences in preoperative demographics (age/BMI) and perioperative complication rates between patient cohorts were assessed using Pearson's chi-squared tests and T-tests when necessary. Binary logistic regression were utilized to find significant factors associated with complication rate. Decision tree analysis was utilized for continuous variables predictive of complication rate. Certain surgical procedures were analyzed for their relationship with post-operative outcomes. RESULTS A total of 13,812 CM-1 patients were isolated (10.12 yrs, 0.62 CCI). Of these pts, 8.2% (1,128) received a complication. From 2003 to 2012, the rate of complications for CM-1 pts decreased significantly (9.6%-5.1%) along with surgical rate (33.3%-28.6%), despite the increase in CM diagnosis (36.3%-42.3%; all p 4.25 and receiving a fusion greater than 4 levels were all significant factors associated with receiving a complication postoperatively (p 4.25 and receiving a fusion greater than 4 levels were all significant factors associated with receiving a complication postoperatively (p CONCLUSIONS Treatment of Chiari malformation has been identified to have improved from 2003 to 2012 with increased identification of diagnosis and decreased complications. Chiari patients undergoing fusions and craniotomies are at a greater risk of postoperative complications especially when the instrumented fusions are performed on >4 levels. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.