A new Canadian guideline aims to help physicians identify and manage blood clots, specifically iliofemoral deep vein thrombosis (DVT), in the groin and thigh.

Iliofemoral DVT, and associated pulmonary embolism, is a potentially fatal condition that affects over 35 000 Canadians a year, with an estimated 60 000 admissions to hospital per year. The guideline, based on the latest evidence and published in CMAJ (Canadian Medical Association Journal), was developed by a team of hematologists, interventional radiologists, vascular surgeons, emergency department physicians and primary care physicians..

"We think this clinical practice guideline fills an important gap in knowledge for care providers by providing a practical approach to a common problem that can have serious implications for patients. The guideline takes into consideration the Canadian socialized health care model and is based on early recognition by primary care providers," states Dr. David Liu, an interventional radiologist at Vancouver General Hospital and lead author of the INTERdisciplinary Expert Panel on Iliofemoral DVT (InterEPID). "Complications associated with DVT can occur years after the presentation of DVT if it is not managed at onset. DVT is a life-threatening condition in the short term, with long- term implications to the patient and (significant downstream cost to) society if not managed properly."

"The InterEPID guideline assists in determining which patients may benefit from early triage and transfer to tertiary care institutions for clot removal and reduction, a critical aspect in both the short-term and long-term management of this condition," states coauthor Dr. Mark Baerlocher.

The guideline team has created a summary of recommendations and a decision tool to help physicians. Highlights include the following:

All hospital staff must have the diagnostic tools to diagnose and determine the severity of iliofemoral DVT. Anticoagulants are recommended for all patients with iliofemoral DVT, but the type and length of treatment will vary according to presentation.

For patients not able to take anticoagulants, use of inferior vena cava filters is recommended with regular follow-up; they should be removed as soon as possible.

Immediate intervention with clot removal is recommended in patients with phlegmasia cerulea dolens to reduce the associated risks of amputation and death.

Clot removal intervention can also be considered for patients who are at low risk of bleeding to minimize possible long-term complications from iliofemoral DVT that may decrease quality of life (postthrombotic syndrome). To manage postthrombotic syndrome, the use of compression stockings is recommended, although the evidence is weak for effectiveness.

Patient follow-up by the primary care physician is important.

"Anticoagulant therapy remains the cornerstone of management, mainly to prevent recurrent venothromboembolism. However, selected patients with iliofemoral DVT may benefit from alternative clot-management strategies, such as inferior vena cava filters, compression therapy, and clot removal or reduction strategies."

"There is often a somewhat disorganized and varied approach to treating iliofemoral thrombosis. This guideline is meant to help standardize the care of Canadian patients with this common condition," the authors conclude.