Commentary on “Risk Factors for Perioperative Hidden Blood Loss After Intertrochanteric Fracture Surgery in Chinese Patients: A Meta-Analysis”

We have read the recent article with great interest entitled “Risk Factors for Perioperative Hidden Blood Loss After Intertrochanteric Fracture Surgery in Chinese Patients: A Meta-Analysis” by Wang et al. ¹ The authors of the study purposed to explore the risk factors of perioperative hidden blood loss in the treatment of intertrochanteric fracture for Chinese patients. While we deeply appreciate the efforts made by the authors in this study, there are some concerns that we would like to address which may induce some improvements in the study.

First, the authors of this article considered the seven studies included to be retrospective studies, so they used the Newcastle Ottawa Quality Assessment Scale (NOQAS to assess the quality of each study. In fact, the NOQAS scale is indeed suitable for assessing retrospective case-control studies and cohort studies. However, after our careful reading of the seven included articles, we confirm that the three studies by Liu et al, ² Tian et al, ³ and Chen et al ⁴ were all prospective, randomized controlled trials. Therefore, the judgment on the study types of these three articles in Table 1 of this study was obviously inappropriate. We recommend using the Cochrane risk of bias tool to assess the quality of the three randomized controlled trials. ⁵

Second, this study explored ten factors associated with perioperative hidden blood loss in the treatment of intertrochanteric fractures and indicated that female patients, patients with a history of hypertension, time from injury to operation (<2 days), operation time (≥60 mins), fracture type (A2.2 to A3.3), and without anticoagulation were the risk factors. In addition, the surgery type of intertrochanteric fractures is also an extremely important risk factor for perioperative hidden blood loss.^2,6-8 However, the authors did not include it in the meta-analysis. In fact, three studies by Zhang et al, ⁶ Liu et al, ² and Zhang et al ⁷ have provided relevant data on surgery type (intramedullary and extramedullary fixation) for intertrochanteric fractures, which can be statistically analyzed.

We would welcome the comments of the authors to address these issues, which will further improve their study.