Rosenthal D, McKinsey JF, Levy AM, Lamis PA, Clark MD.
Use of the Greenfield filter in patients with major trauma.
Cardiovasc Surg 1994 Feb;2(1):52-5

Georgia Baptist Medical Center, Department of Vascular Surgery, Atlanta.

Patients with major trauma often cannot be given the benefit of preventive
measures such as pneumatic compression boots and low-dose heparin against
pulmonary embolism. The Greenfield filter is accepted as a safe and effective
method of prophylaxis of this complication. The aim of this study was to evaluate
the efficacy of placement of the Greenfield filter in 161 patients with major
trauma. Between January 1984 and July 1988, 94 patients with an injury severity
score (ISS) of > 16 were treated. This score is predictive of a mortality rate of
at least 10% and defines major trauma based on anatomic injury. Some 20% (19 of
94) of these patients developed deep vein thrombosis despite standard
prophylactic measures and 8% (eight of 94) suffered pulmonary embolism, two of
which were fatal. Pulmonary embolism occurred without antecedent evidence of deep
vein thrombosis in another 15% of patients (14 of 94), three of which caused
death. From August 1988 until July 1992, of 67 other patients with an ISS > 16,
13% (nine of 67) developed deep vein thrombosis and 1% (one of 67) had a
pulmonary embolism; this was not statistically significant (P > 0.25). Of these
67 patients who were considered to be at high risk of pulmonary embolism, because
of a contraindication to anticoagulation or physical impediment to sequential
compression boots, 29 had prophylactic placement of a Greenfield filter. No
pulmonary emboli occurred in these patients. During long-term follow-up (mean
32.8 (range 4-58) months), 84% of the surviving patients (21 of 25) underwent
duplex ultrasonography of the inferior vena cava; patency of the vessel was
confirmed in all patients.