Malaysian orthopaedic surgeons' approach to venous thromboembolic disease prophylaxis: attitudes and practice

Journal of Orthopaedic Surgery, Dec 2003 by Zairul-Nizam, Z F, Gul, Y A

ABSTRACT

Purpose. To survey Malaysian orthopaedic surgeons' attitudes to and use of venous thromboembolic disease prophylaxis.

Methods. A total of 144 orthopaedic surgeons from various governmental and private institutions responded to a questionnaire.

Results. Only slightly more than half of these surgeons considered venous thromboembolic disease as common a problem in Malaysia as in western countries. The majority of surgeons (91.0%) reported using prophylaxis selectively for patients based on various indicators such as risk grading of surgery, obesity, and malignancy etc. Bleeding tendencies were cited as the greatest fear against the use of pharmacological prophylaxis. Low-molecular-weight heparin appeared to be the most commonly used pharmacological prophylaxis, used either singly or in combination with other forms of prophylaxis. The majority of surgeons employed prophylaxis until their patients were mobile.

Conclusion. There should be greater awareness among surgeons in Malaysia of the need for protection against venous thromboembolic disease. Current practice needs to be reviewed and further recommendations made for existing protocols.

Key words: low molecular weight heparin; pulmonary embolism; venous thrombosis

INTRODUCTION

Venous thromboembolic disease (VTE) remains an enigma among health care professionals the world over. The problems of post-phlebitic syndrome and pulmonary embolism remain serious potential sequelae, especially among orthopaedic patients. In the absence of prophylaxis, deep venous thrombosis (DVT) develops in up to 75% of patients following total knee arthroplasty, and 50% of patients following total hip arthroplasty.1,2 The frequency of fatal pulmonary embolism among orthopaedic patients ranges from 0.1% to 7%, depending on the nature of the surgery performed.2 The use of prophylaxis against VTE-often a combination of pharmacological and mechanical modes-is reported to reduce the risk among orthopaedic patients by 64%.3 Recently, the rationale behind prophylaxis has come under scrutiny. It has been questioned whether the use of pharmacological prophylaxis achieves any major gain in reducing the incidence of symptomatic thrombosis and fatal pulmonary embolism.4 This question remains unanswered, although the overall cost-effectiveness of prophylaxis for the prevention of VTE and its sequelae has clearly been shown.5-7

Despite the many studies and recommendations developed specifically to address the problem of VTE,2,5,7-8 it is not known what influence these studies have had on the practice of Malaysian orthopaedic surgeons. This issue has been addressed elsewhere,1,9-11 but such information is lacking in the local setting. Consequently, we decided to conduct a survey among Malaysian orthopaedic surgeons to determine their attitudes and practice with respect to VTE prophylaxis.

METHOD

A standard questionnaire was developed addressing aspects of a surgeon's attitude towards and practice of VTE prophylaxis. The surgeon's use of prophylaxis, indications for usage, and reasons for not using prophylaxis were explored, as well as whether the surgeon used any protocol for prophylaxis. The questionnaire was given to the majority of orthopaedic surgeons in Malaysia during attendance at a scientific meeting.

RESULTS

A total of 144 orthopaedic surgeons responded to the questionnaire. Of this number, 86 (59.7%) surgeons were from Ministry of Health hospitals, 31 (21.5%) were employed by university hospitals, and 27 (18.8%) were from private institutions. 83 (57.6%) of the respondents thought that VTE was as common in Malaysia as in western countries.

Use of VTE prophylaxis

Seven (4.9%) surgeons used VTE prophylaxis for all their patients, while 4 (2.8%) used VTE prophylaxis sporadically. The majority of surgeons, i.e. 131 (91.0%), used VTE prophylaxis selectively. Prophylaxis against VTE was not used at all by 2 (1.4%) surgeons-a paediatric orthopaedic surgeon, and a surgeon specialised in microsurgery.

Indications for VTE prophylaxis

The responses of the 131 surgeons who used VTE prophylaxis selectively were further examined. Indications for selective use of VTE prophylaxis are shown in Fig. 1. The majority of surgeons, i.e. 107 (81.7%), cited risk grading of the surgery as the main indicator. Risk grading was the perception of risk based on the nature of the surgery performed, and specific patient characteristics. Previous incidence of VTE in patients was another major indication among 104 (79.4%) surgeons, while 86 (65.6%) cited concurrent medical or surgical illnesses, and resultant pharmacotherapy, such as the use of steroids, as another reason for instituting VTE prophylaxis. Obesity was cited by 84 (64.1%) surgeons as an indication, while age and malignancy were cited by 72 (55.0%) and 56 (42.7%) surgeons, respectively.

Reasons for not instituting VTE prophylaxis

The reasons given for not instituting pharmacological prophylaxis are shown in Fig. 2. Among the 131 surgeons who used VTE prophylaxis selectively, 25 (19.1%) did not use any prophylaxis when they believed the particular patient had a low risk of developing DVT, based on the nature of the surgery and the patient's characteristics. 39 (29.8%) surgeons did not use pharmacological prophylaxis when faced with the possibility of bleeding (either undesired or excessive) having a negative impact on the outcome of treatment. The cost of a particular prophylactic agent was a factor, particularly for the newer low-molecularweight heparins (LMWH), with 15 (11.5%) surgeons not employing the said prophylaxis. However, for surgeons in private practice, cost was not a factor influencing use of pharmacological prophylaxis. 11 (8.4%) surgeons took the side effects of pharmacological agents into account when deciding not to institute VTE prophylaxis. Finally, religious practice of the patient was reported to have precluded the use of prophylaxis by 4 (3.1%) surgeons. This was particularly notable with respect to porcine-based agents and Muslim patients.