Objectives: To identify and characterize cases of
potentially preventable venous thromboembolism (VTE): cases for which
thromboprophylaxis was indicated, according to the American College of
Chest Physicians (ACCP) consensus guidelines for VTE prevention, yet
was administered inadequately.
Design: A historical
cohort study to examine all cases of deep vein thrombosis and pulmonary
embolism from 1996 to 1997 at a large teaching hospital. Of these, we
determined the proportion that was potentially preventable. We examined
the reasons for inadequacy of prophylaxis and the setting in which
preventable VTE occurred.
Results: Of 253 objectively
diagnosed cases of VTE in 245 patients, 44 cases (17.4%) were
considered potentially preventable. This represented two thirds of all
VTE cases for which thromboprophylaxis had been indicated (n = 65).
Of preventable cases, the most frequent reason for inadequacy of
prophylaxis was omission of prophylaxis (47.7%), followed by
inadequate duration of prophylaxis (22.7%), and by incorrect type of
prophylaxis (20.5%). Surgical and medical indications for
thromboprophylaxis that were common among preventable cases included
nonorthopedic surgery, admission to hospital for pneumonia, and stroke
with lower limb paralysis. Underlying risk factors for VTE that were
common among preventable cases included recent immobility, active
cancer, and obesity.
Conclusions: One of six cases of
all VTE and two of three cases of VTE for which thromboprophylaxis had
been indicated could potentially have been prevented had physicians
followed the recommended ACCP guidelines. Inadequacy of prophylaxis was
most often caused by omission of prophylaxis. Missed opportunities for
prevention occurred most commonly in the settings of nonorthopedic
surgery, pneumonia, and stroke.