Risk factors for hidden blood loss in unilateral biportal endoscopic lumbar interbody fusion: A single-center retrospective study

Abstract

Abstract Background An increasing number of lumbar degenerative diseases are being treated with unilateral biportal endoscopic interbody fusion surgery (ULIF). However, hidden blood loss (HBL) is often ignored during this procedure. We investigated the amount and influencing factors of HBL in ULIF surgery in this study. Methods Between October 2020 and November 2023, 100 patients were retrospectively examined, and their clinical and radiological data were analyzed. In order to investigate an association between patient characteristics and HBL, Pearson or Spearman correlation analyses were performed.To identify the clinical or radiological factors associated with HBL, multivariate linear regression was carried out . Results The mean HBL was 255.84 ± 290.89 ml, accounting for 62.48% of the total blood loss. A Pearson or Spearman correlation analysis revealed a positive relationship between HBL and American Society of Anaesthesiologists (ASA)classification (P = 0.009), operation time (P = 0.004), numer of operation level (P = 0.046) and paraspinal muscle thickness (P = 0.043),but a negative relationship with tranexamic acid use (P = 0.001). According to a multivariate linear regression analysis, HBL correlated positively with the ASA classification (P = 0.038) and operation time (P = 0.046), but negatively with the use of tranexamic acid (P = 0.001). Conclusion Patients undergoing ULIF surgery incurred a great deal of HBL. More importantly, ASA classification, operation time and tranexamic acid use were independent risk factors for HBL.