Risk factors of significant intraoperative blood loss in unilateral expansive open-door cervical laminoplasty for cervical compressive myelopathy: A retrospective observational study.

To investigate the independent risk factors of significant intraoperative blood loss (SIBL) in cervical spondylotic myelopathy (CSM) patients who receive unilateral expansive open-door cervical laminoplasty (UEOCL) treatment. UEOCL is a representative method for surgically treating CSM, while SIBL (with an IBL ≥ 500 mL) cannot be completely avoided. The 341 patients who received UEOCL for CSM treatment at our hospital from 2013 to 2019 fell into the SIBL group (n = 37) and the non-SIBL group (n = 304). We retrospectively recorded demographic, surgical and radiographic data for the investigation of the independent risk factors related to SIBL. Statistical analysis relied on R software. Univariate and multivariate logistic regression analyses served for more deeply examining the significance of these factors. CSM patients presented an incidence of SIBL of 10.9% (37/341) during UEOCL. According to a multivariate analysis, duration of operation ≥ 150 minutes (OR, 2.598; 95% CI, 1.136-5.942; P = .024), preoperative FIB (OR, 0.480; 95% CI, 0.245-0.941; P = .033) and surgical-level OPLL (OR, 2.668; 95% CI, 1.235-5.765; P = .013) could independently indicate the risk of SIBL. As for patients with SIBL, an obvious increase was not detected in the postoperative drainage (P = .636), the length of stay (P = .392) and the hospitalization cost (P = .389) but it was in the frequency of blood transfusions (P < .001). Duration of operation ≥ 150 minutes, preoperative FIB and surgical-level OPLL were independent risk factors for SIBL. Patients with SIBL had no significant more postoperative drainage, longer length of stay and higher hospitalization costs, but higher frequency of blood transfusion.