Hidden Blood Loss and Its Influential Factors After Laparoscopy-Assisted Gastrectomy for Gastric Cancer.

<bold>Introduction: </bold>Laparoscopy-assisted gastrectomy (LAG) is a minimally invasive procedure for the treatment of gastric cancer. It is generally thought that a minimally invasive technique results in less visible blood loss during the surgery. Nevertheless, a meaningful perioperative hidden blood loss (HBL) is often ignored. In this study, we investigated the amount of HBL and the influential factors after LAG for gastric cancer.<bold>Methods: </bold>A retrospectively analyzed clinical data of 62 consecutive patients who underwent laparoscopy-assisted total or distal gastrectomy at our center from May 2016 to May 2017. The HBL was calculated according to Gross's and Nadler's formula. The data of patient gender, age, height, weight, body mass index, preoperative and postoperative hematocrit, postoperative drainage, albumin loss, diabetes mellitus, and hypertension were analyzed by multivariate linear regression analysis. The type of surgical reconstruction was analyzed by one-way analysis of variance. The difference between the preoperative blood pressure and postoperative blood pressure was measured by paired sample t-test and boxplot.<bold>Results: </bold>The HBL was 322.2 ± 195.9 mL (64.3% ± 14.1% in total blood loss [TBL]), the TBL was 475.6 ± 222.8 mL, and the hemoglobin (HB) loss was 15.0 ± 8.7 (11.5% ± 6.1% of HB level loss). Multivariate linear regression analysis revealed that gender, hypertension, and albumin loss between preoperation and postoperation are influential factors of HBL in patients after LAG for gastric cancer. Compared to male patients, female patients are positively associated with HBL.<bold>Conclusion: </bold>In our study, we found HBL is a significant segment of TBL and is much larger than what we considered previously in LAG for gastric cancer. Gender, hypertension, and albumin loss are significantly correlated with HBL. Therefore, paying attention to HBL is significant for promoting clinical treatment and ensuring patients' safety. [ABSTRACT FROM AUTHOR]