Preoperative prediction of early mortality after surgery for spinal metastases.

OBJECTIVE The objective of this study was to provide a convenient preoperative prediction of the risk of early postoperative mortality. MATERIALS AND METHODS This retrospective study included patients who underwent surgery for spinal metastasis at our hospital between 2009 and 2021. Preoperative blood test data of all patients were collected, and the survival time was calculated by dividing the blood data. A multivariate analysis was conducted using a Cox proportional hazards model to identify prognostic factors. RESULTS The study population included 83 patients (average: 64.5 years), 22 of whom died within 3 months. The most common lesion was the thoracic spine, and incomplete paralysis was observed in 57 patients. The surgical methods included posterior implant fixation (n = 17), posterior decompression (n = 31), and posterior decompression with fixation (n = 35). In the univariate analysis, the presence of abnormal values was significantly associated with postoperative survival in six preoperative blood collection items (hemoglobin, C-reactive protein, albumin, white blood cell, gamma-glutamyl transpeptidase, and lactate dehydrogenase). In a multivariate analysis, four test items (hemoglobin, C-reactive protein, white blood cell, and lactate dehydrogenase) were identified as independent prognostic factors.Comparing cases with ≥3 abnormal values among the above four items (high-risk group; n = 23) and those with ≤2 (low-risk group; n = 60), there was a significant difference in survival time. In addition, it was possible to predict cases of early death within 3 months after surgery with 73% sensitivity and 89% specificity. CONCLUSIONS The study showed that four preoperative blood test abnormalities (hemoglobin, C-reactive protein white blood cell, and lactate dehydrogenase) indicated the possibility of early death within 3 months after surgery.