Joeky Senders

33 Thirty-day outcomes after craniotomy (all p<0.001, Table 3). Older age, higher ASA-classification, dependent functional status, elevated WBC, low hematocrit, and ventilator dependence were predictors of hospital stay beyond ten days (all p<0.001). Higher ASA-classification and elevated WBC were predictors of reoperation within 30 days (both p<0.001) (Table 4). Higher ASA- classification and dependent functional status were predictors of readmission (both p<0.001). Older age, higher ASA-classification, and dependent functional status were predictors of 30-day mortality (all p<0.001) (Table 5). Missingness ranged between 6.2% and 10.6% depending on the specific outcome measure studied. Including missingness as an additional group did not significantly alter the results. Discussion Despite improved perioperative management, the overall rate of short-term postoperative major complications, extended length of stay, reoperation, readmission, andmortality for patients treated with a craniotomy for primarymalignant brain tumors remains considerably high. This multicenter registry study provides a descriptive analysis and identifies predictors of 30-day postoperative outcomes after craniotomy for these lesions. The patient population in this study was technically classified as all those with primary malignant brain tumors based on ICD-9 codes. Gliomas represent close to 80% of primary malignant brain tumors; 1 however, there is no standard ICD-9 code specific for glioma. The Central Brain Tumor Registry of United States (CBTRUS) argues that multiple combinations of ICD histology codes can be used to define gliomas, and their approach was modeled in this study. 1 Therefore, these results are primarily applicable to glioma patients and should be put in the context of previous outcome research on glioma patients. Many multicenter studies have reported on short-term outcomes after craniotomy for brain tumors; 4-14 however, fewhave specifically analyzed primarymalignant brain tumor or glioma patients. 10-12,14,15 Previous multicenter studies found similar length of stay, readmission rate, and mortality rate in glioma patients 10-12,15 and brain tumor patients overall, including primary benign brain tumors, metastases, meningiomas, and cranial nerve tumors. 7,9,13,28 The rates of overall and major complications in the current study were similar to other studies analyzing glioma patients, 11,14 but fall in the upper range of studies that analyzed all brain tumor patients. 7,13 This suggests that the postoperative course of glioma patients is more frequently complicated by adverse events compared