As the population of elderly persons increases, managing complications following hip fractures has become even more critical. Patients with hip fractures are at high risk of venous thromboembolism (VTE), the second most common complication after surgery for treatment of hip fractures¹⁾. The risk of VTE was >20-fold higher for patients undergoing surgery for treatment of hip fracture compared with those undergoing simple gynecological surgery and until relatively recently the rate of VTE after surgery for treatment of hip fracture showed an annual increase in Korea²⁾. The reported incidence of VTE in patients with hip fractures ranges from 1.6-11.1% in Korea^2,3). This condition can be life-threatening for patients, and surgeons could be faced with legal issues and psychological burdens. Based on these issues, various guidelines for prevention of VTE have been suggested in Western societies. However, the reported incidence of VTE after surgery for treatment of hip fractures is lower in Asians compared with that in Caucasians⁴⁾, therefore, application of Western guidelines in Korea may be associated with problems such as unnecessary treatment or complications. In addition, most of the guidelines are more than 10 years old. Therefore, determining the current status of VTE prevention in hip fracture patients in Korea can provide important information for use in re-establishing standardized guidelines and educational programs. The aim of this study was to examine the level of awareness and current status of VTE prevention with regard to the treatment of hip fractures in Korean patients.

A survey questionnaire on protocols for prevention of VTE was administered to 570 members of the Korean Hip Society using Google forms in July 2022. The questionnaire was developed by the authors based on the VTE prevention guidelines. There were no inclusion or exclusion criteria for respondents. The survey was conducted over a period of 10 days. Data were collected automatically when the respondent filled in the answers, and the respondent’s personal information was not included. A total of 97 surgeons participated in the questionnaire-based survey, with a response rate of 17.0% (Table 1). The questions were related to (i) experiences with VTE events in the past year, (ii) protocol for prevention of VTE in standard/high-risk patients, (iii) identification of risk factors for screening groups at high risk for VTE before surgery, and priority of the risk factors, (iv) method and duration of mechanical prophylaxis in standard/high-risk patients, (v) drugs and duration of chemical prophylaxis in standard/high-risk patients, (vi) consideration of wound complications during chemical prophylaxis, (vii) postoperative screening for VTE, and (viii) relationship between administration of tranexamic acid (TXA) and occurrence of VTE (Supplementary Material 1). According to Korean Hip Society Prevention Guidelines⁵⁾, high-risk patients are defined as those with at least one of the following factors: over 60 years old, obesity (body mass index over 30 kg/m²), dehydration, one or more concomitant medical diseases (heart disease, metabolic, endocrine or respiratory disease, acute infectious disease, inflammatory disease), taking hormone therapy or contraceptives containing estrogen, currently diagnosed with cancer or undergoing treatment for cancer, critical care admission, varicose vein with phlebitis, predisposition to thrombosis, or history of VTE.

Incidence of VTE ranging from 40% to as high as 80% has been reported in patients with hip fractures who have not received prophylaxis^6,7). Pulmonary embolism is a severe complication with a high mortality rate. However, application of appropriate prophylaxis could significantly reduce the incidence of VTE⁸⁾.

With an emphasis on the high incidence of VTE, various medical societies including the American College of Chest Physicians⁹⁾, National Institute for Health and Clinical Excellence¹⁰⁾, and American Academy of Orthopedic Surgerons¹¹⁾ have provided a summary of recommendations for prevention. In addition, a summary of expert opinions on the prevention of VTE was recently presented by the Asia-Pacific Region Venous Thromboembolism Consensus Group¹²⁾. In 2011, guidelines were published by the Korean Hip Society based on the situation in Korea⁵⁾. However, most of the references included in the guidelines were over 10 years old, thus determining the current situation is difficult¹³⁾. In addition, there is no clear consensus with regard to which prevention protocols are the safest and most effective. This diversity can present a legal argument regarding the evidence of treatment. Understanding the current status of prevention and providing recommendations that are appropriate to the domestic situation is essential. Therefore, we conducted a survey to assess the current status of VTE prevention with regard to treatment in patients with hip fractures in Korea.

VTE prophylaxis was performed by all participants in patients with hip fractures, and dual prophylaxis was applied in the high-risk group by most of them. Most guidelines recommend an appropriate combination of mechanical and chemical prophylaxis^9,12). An evaluation of risk factors for VTE should be performed preoperatively, and more aggressive prophylaxis is recommended for patients at high risk of VTE. Application of mechanical prophylaxis alone is recommended for patients with a high risk of bleeding^5,12).

A history of VTE and concomitant medical diseases were identified as important risk factors for VTE among participants in this study. A history of previous VTE, varicose veins, congestive heart failure, medical history of thromboembolic stroke, and family history of VTE were found to be risk factors associated with a significant increase in the incidence of VTE after surgery for treatment of a hip fracture¹²⁾.

According to all guidelines, mechanical prophylaxis is recommended for patients undergoing surgery for the treatment of a hip fracture unless there are contraindications. The effectiveness of mechanical prophylaxis including IPCDs, venous foot pump devices, and graduated compression stockings has been demonstrated, and using them until the patient is able to walk is recommended^5,14). Because preoperative VTE rates as high as 11-12% have been reported, mechanical prophylaxis should be initiated before surgery^3,15).

LMWH is the most commonly recommended prophylactic agent. Participants in our study also preferred LMWH and DOACs. DOACs such as apixaban, dabigatran, and rivaroxaban, which are taken orally, are easy to administer and have positive effects, and their use has shown a recent increase. Despite some differences between drugs, administration for 3-5 weeks is recommended, considering that the incidence of acute VTE may show a rapid increase up to five weeks after surgery^9,16). There are some concerns regarding the incidence of wound complications during chemical prophylaxis using LMWH and DOACs; care must be taken in wound management. For this reason, some studies have recommended administration of low-dose LMWH (20 mg enoxaparin once daily) only before discharge or aspirin alone^17,18).

Routine tests for VTE were not performed after surgery by more than half of the participants. VTE could occur even three months after surgery, therefore, the occurrence cannot be completely ruled out by routine screening during the acute phase after surgery, and problems with cost and overtreatment may arise. Therefore, routine screening before discharge is not recommended^9,12).

Approximately half of the participants answered that there was no association between the administration of TXA and the occurrence of VTE. Several studies have demonstrated that the risk of VTE was not increased by administration of TXA during surgery for treatment of a hip fracture and blood loss and transfusion requirements were reduced^19,20).

The strength of our study is that we evaluated the current status of VTE prevention in Korea. The incidence of VTE after surgery for treatment of a hip fracture is lower in Koreans compared with Caucasians²⁾. Therefore, application of foreign guidelines may result in development of issues and complications. Despite the low overall incidence of VTE in Korea, the results of this study, showing that 61.9% of the respondents had encountered a patient with symptomatic VTE at least once in the past year, suggest that prevention of VTE should never be disregarded. It may be time to update domestic guidelines according to the change in patient characteristics and treatment modalities. In a survey of members of the American Association of Hip and Knee Surgeons conducted in 2008²¹⁾, 53% of respondents reported that they had changed their VTE treatment regimen as a result of the availability of additional guidelines and pharmacologic agents. The results of our study would be helpful in establishing updated guidelines that are suitable for Korean patients.

This study has several limitations. First, the study included a small number of participants. Because only the responses of the respondents were analyzed in our study, there may be non-response bias. In addition, because this study was conducted as a survey to identify trends among participants, the degree of choice of answers is not a criterion for use in determining whether a practice is right or wrong.

VTE prophylaxis was performed by all respondents for treatment of patients with hip fracture. Dual prophylaxis was applied by almost all participants in patients with high-risk of VTE. A routine screening test for VTE was not performed after surgery by more than half of the respondents. Wound complications require attention when prescribing chemical prophylaxis. The results of our survey provided information regarding the current status of VTE prevention for patients undergoing surgery for treatment of hip fracture in Korea and provided a baseline for establishing educational programs and guidelines in the future.

Answers regarding experiences with venous thromboembolism (VTE) in patients with hip fracture during the past year. (A) Symptomatic VTE. (B) Asymptomatic VTE.

Table 1. Demographics of 97 Participants