Preoperative Use of Blood-Thinning Drugs Is Safe for Patients With Cancer
Among patients undergoing major cancer operations, the preoperative use of blood-thinning drugs such as heparin does not increase rates of major bleeding or transfusions, and is associated with a decreased risk of blood clots, according to new study results published by Selby et al in the Journal of the American College of Surgeons.
Venous thromboembolism is a common occurrence in patients with cancer. Those undergoing major operations are at higher risk of deep-vein thrombosis. While administering blood-thinning drugs after surgical procedures has become a common practice, no large studies have investigated the safety and efficacy of giving a single preoperative dose of blood thinners, in addition to postoperative doses, to patients undergoing major cancer operations. During smaller procedures, doctors typically administer clot-preventing medication, but its blood-thinning action in the body can lead to excessive bleeding, transfusions, and other serious issues.
ACS NSQIP
Upon analyzing the American College of Surgeons National Surgical Quality Improvement Project (ACS NSQIP) database, the research team discovered that their institution, Memorial Sloan Kettering Cancer Center (MSKCC), had higher than expected rates of deep-vein thrombosis and pulmonary embolism. NSQIP is the leading nationally validated, risk-adjusted, outcomes-based program to measure and improve the quality of surgical care in hospitals, and was the tool that prompted the researchers to set up the trial and work on this important quality improvement parameter. At the request of Peter T. Scardino, MD, FACS, Chairman of Surgery at MSKCC, the research team set out to identify the reason for their venous thromboembolism rate and to lower it.
“We weren't sure if our [venous thromboembolism] rate was due to the complexity of our operations, the fact that our patients had cancer, or that we weren't administering heparin, which could decrease the blood clots,” said Vivian Strong, MD, FACS, Associate Attending Surgeon and NSQIP Surgical Champion at MSKCC.
“There was serious concern that administering preoperative [venous thromboembolism] prophylaxis to our patients, who undergo extensive surgical resection, would increase the risk of bleeding. Knowing from NSQIP that we had a higher than expected [venous thromboembolism] rate, the question was whether it was safe to expose our patients to the additional bleeding risk from [venous thromboembolism] prophylaxis,” added Luke V. Selby, MD, the Department of Surgery's Outcomes Research Fellow.
Study Findings
For this study, Dr. Selby and colleagues selected 2,058 patients undergoing major operations for cancer at MSKCC to receive preoperative venous thromboembolism prophylaxis (low-molecular-weight heparin or unfractionated heparin). The investigators then compared bleeding, transfusion, and venous thromboembolism rates from that cohort of cancer patients with a group of 4,960 cancer patients who had already undergone a major surgical procedure a year earlier, but did not receive preoperative prophylaxis.
The study findings showed that providing one dose of anticoagulant medicines before surgery is safe in cancer patients undergoing major operations. Patients who had received preoperative venous thromboembolism prophylaxis had lower transfusion rates (17% vs 14%) without a difference in major bleeding. In addition, rates of deep-vein thrombosis and pulmonary embolism were significantly lower in the prophylaxis group (1.3% vs 0.2%; and 1.0% vs 0.4%, respectively).
Because of the findings from this study, MSKCC has adopted a routine anticoagulation approach for patients who meet certain selection criteria. “This research has been a practice-changing study for our institution,” Dr. Strong said. “Our study results demonstrate to other institutions that you can use preoperative [venous thromboembolism] prophylaxis safely, so I think that it has very broad-reaching, practice-changing implications.”
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
