Thrombocytopenia associated with unrecognized non-alcoholic fatty liver disease is an independent predictor of perioperative significant blood loss in cervical laminoplasty

OBJECTIVE To identify risk factors for significant blood loss (SBL) in cervical laminoplasty, especially regarding thrombocytopenia and coagulopathy resulting from non-alcoholic fatty liver disease (NAFLD). METHODS We retrospectively investigated differences in patient background data, laboratory data at the time of admission, and surgery-related data of 317 patients who underwent cervical laminoplasty and were divided into SBL (estimated blood loss [EBL] + drainage [D] ≥500 g) and non-SBL (EBL + D < 500 g) groups. To evaluate liver status, we used the fibrous 4 index and considered fibrous 4 index ≥1.85 as a representative phenotype for NAFLD with liver fibrosis. In addition, the risk factor for perioperative SBL was investigated using multiple logistic regression analysis, and the cutoff value was calculated. RESULTS Incidence of perioperative SBL in cervical laminoplasty was 7.3% (23/317). Compared with the non-SBL group, the SBL group demonstrated significantly lower platelet count (PLT), lower aspartate aminotransferase, longer operation time, and greater number of opened laminae. According to multivariate analysis, lower PLT and a greater number of opened laminae were identified as significant risk factors for perioperative SBL. The cutoff value of PLT for predicting SBL was determined to be 16.7 × 104/μL using a receiver operating characteristic curve. The liver fibrosis group revealed significantly lower PLT and greater EBL + D than the non-liver fibrosis group. CONCLUSIONS Thrombocytopenia is an independent predictor of perioperative SBL in cervical laminoplasty. Thus, patients with mild thrombocytopenia that may be associated with NAFLD must be carefully monitored to avoid perioperative SBL.