Analysis of risk factors for perioperative hidden blood loss in patients undergoing transforaminal lumbar interbody fusion

OBJECTIVE: This study was performed to analyze the correlation between perioperative hidden blood loss (HBL) and the general condition of patients undergoing transforaminal lumbar interbody fusion (TLIF). METHODS: We retrospectively analyzed patients who underwent TLIF from July 2017 to July 2019 in our hospital. Sex, age, body mass index, underlying diseases, American Society of Anesthesiologists classification, coagulation function, preoperative and postoperative hemoglobin level and hematocrit, surgery time, fusion level, intraoperative blood loss, and drainage volume were recorded. Postoperative complications were also recorded. The amount of HBL was calculated, and its correlation with related variables was analyzed. RESULTS: The mean surgery time was 153.32 ± 54.86 minutes. The total perioperative blood loss was 789.22 ± 499.68 mL, including HBL of 315.69 ± 199.87 mL. Pearson correlation analysis showed statistically significant differences in HBL according to the body mass index, hypertension, fibrinogen, surgery time, and fusion level. Multiple linear regression analysis indicated that the surgery time and fusion level were independent risk factors for HBL. CONCLUSIONS: A certain amount of HBL occurs in TLIF surgery and cannot be ignored in daily clinical work. The operation time and surgery level are independent risk factors for HBL.