A randomized, prospective trial of deep venous thrombosis prophylaxis in aortic surgery
L. A. Killewich, M. A. Aswad, G. P. Sandager, M. P. Lilly and W. R. Flinn
Department of Surgery, University of Maryland School of Medicine, Baltimore, USA.
OBJECTIVES: To study the incidence of postoperative deep venous thrombosis
(DVT) in patients undergoing elective aortic reconstruction and to
determine if aggressive DVT prophylaxis would reduce the incidence of DVT
in these patients. DESIGN: Randomized, prospective trial. SETTING:
University hospital and Veterans Affairs hospital. PATIENTS: One hundred
patients undergoing aortic reconstruction for aneurysmal or occlusive
disease randomized to receive DVT prophylaxis (treatment group) or no
prophylaxis (control group). Exclusion criteria included a history of DVT,
long-term anticoagulant use, or a malignant neoplasm. During the study
period, 12 patients were ineligible for follow-up. Ninety-eight patients
completed the trial, including 50 patients in the treatment group and 48
patients in the control group. Two patients in the control group died
postoperatively of unrelated causes. INTERVENTION: Patients in the
treatment group received DVT prophylaxis using a combination of low-dose
heparin sodium therapy (5000 U every 12 hours) and calf-length intermittent
mechanical compression devices. Control patients received no DVT
prophylaxis. MAIN OUTCOME MEASURES: The occurrence of acute lower extremity
DVT diagnosed by interval venous duplex ultrasound scan surveillance
performed on postoperative days 1, 3, and 7. RESULTS: The overall incidence
of proximal DVT in this study was 2%. One case of DVT occurred in the
treatment group, and the other one occurred in the control group. There was
no statistically significant difference (P = .99) in the incidence of DVT
between the 2 groups. One patients in the control group had a nonfatal
pulmonary embolus (1% of the patients overall). CONCLUSIONS: The incidence
of proximal DVT in patients undergoing elective aortic reconstruction is
low compared with patients undergoing other major intraabdominal general
surgical procedures. The use of aggressive DVT prophylaxis did not reduce
the risk of postoperative proximal DVT in this study. The selective use of
DVT prophylaxis in patients undergoing elective aortic surgery should be
based on associated concomitant or evolving risk factors.
