Does preoperative embolization help to lower surgical blood loss in nonvascular metastatic spine tumor surgery?

Introduction: We aim to identify if embolization prior to resection of spinal column metastases originating from non-vascular (not renal, hepatocellular, and thyroid) tumors improves blood loss.

Methods: Patients who underwent resection of vertebral column metastases (excluding renal, hepatocellular, and thyroid) were identified. Uni- and multivariate analyses compared effect of embolization on blood loss and transfusion rates. Next, embolized and non-embolized cohorts were propensity-score matched (PSM)(1:3 on age, sex, BMI, corpectomy, levels operated) and compared.

Results: In total, 290 patients (45% female) with non-vascular spinal column metastases were identified with mean age 60.4 years and preop hemoglobin level (Hgb=11.7). 37 patients (12.8%) patients underwent embolization. The cohorts did not differ significantly in age, sex, BMI, or preop Hgb. The embolized cohort had more corpectomies (78.4% vs 60.5%, p=0.035) and levels operated (7.2±2.5 vs 5.6±2.4, p< 0.001). The embolized and non-embolized cohorts had no significant differences in EBL (1424±1269 vs 1031±1504 ml), change (post—preop) in Hgb, pRBC transfusions rates (50.0% vs 50.2%) or units transfused (3.6±3.1 vs 3.1±3.4)(p>0.05). However, the embolized cohort had higher postop Hgb (10.7±1.4 vs 10.2±1.3, p=0.036). On multivariate analysis, increased levels operated (EBL β-Coef:124.6, p=0.003; Transfusion OR per 1-level increase: 1.14, 95%CI:1.004-1.30) and corpectomy (EBL β-Coef: 503.8, p=0.017; Transfusion OR: 3.80, 95%CI:2.03-7.27) were associated with higher EBL and increased transfusion rates. Corpectomy (β-Coef:-0.54, p< 0.001) was associated with lower higher postop Hgb levels and decreased change in Hgb, while higher preop Hgb (β-Coef:0.32, p< 0.001) and embolization (β-Coef:0.45, p=0.032) were associated with higher postop Hgb levels and decreased change in Hgb. After PSM, 120 patients (35 [25%] embolized) were included. The embolized and non-embolized cohorts had no significant differences in age, sex, BMI, pre- and postop Hgb, EBL, and transfusion rates.

Conclusion : Embolization prior to resection of non-vascular spinal column metastases did not reduce EBL or pRBC transfusion rates.