A randomized, prospective trial of deep venous thrombosis prophylaxis in aortic surgery. Prevention of postoperative deep venous thrombosis and pulmonary emboli with combined modalities. Is DVT prophylaxis overemphasized? A randomized prospective study. Drug prevention of postoperative deep vein thrombosis. A compararative study of calcium heparinate and sodium pentosan polysulfate. Anticoagulant therapy in deep venous thrombosis. A randomized controlled study. Prevention of postoperative deep vein thrombosis in cancer patients. A randomized trial with low molecular weight heparin (CY 216). Antibiotic prophylaxis in vascular reconstructive surgery: a double-blind placebo-controlled study. Efficacy of oral anticoagulants compared with aspirin after infrainguinal bypass surgery (The Dutch Bypass Oral Anticoagulants or Aspirin Study): a randomised trial. Case report: superior vena caval obstruction treated by thrombolysis, mechanical thrombectomy and metallic stents.
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.
                Randomized, prospective trial.
                University hospital and Veterans Affairs hospital.
                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.
                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.
                The occurrence of acute lower extremity DVT diagnosed by interval venous duplex ultrasound scan surveillance performed on postoperative days 1, 3, and 7.
                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).
                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. Worldwide statistics reveal that 25 to 40 per cent of patients who are over the age of 40 years and operated on for 1 or more hours will develop a deep venous thrombosis (DVT). The studies reviewed in this paper were performed to evaluate several modalities and compare their effectiveness in preventing DVT in postoperative patients. In the first study, five modalities plus a control group were evaluated in 562 patients from five surgical specialties. The incidence of DVT in the control group was 35 per cent. Though most of the pharmacologic agents were effective in reducing the incidence of DVT, the antistasis devices (gradient elastic stockings and intermittent pneumatic compression) were most effective. The purpose of the second study was to evaluate the effectiveness of combining a pharmacologic drug with an antistasis modality. Deep venous thrombosis was virtually eliminated in this group of 328 patients. There was only a 1.5 per cent incidence of DVT in the treated population as compared to a 26.8 per cent incidence in the control group. Thus, it seems that combining one antistasis and one pharmacologic agent greatly reduces the incidence of lower extremity thrombi. I-125 fibrinogen scanning was the most sensitive test in detecting DVT and had an accuracy of 97 per cent. This study was designed to prospectively evaluate a previously published prognostic index for predicting deep venous thrombosis (DVT) in general surgical patients with conventional prophylaxis. Patients undergoing procedures of at least 1 hr duration (abdominal, thoracic, head and neck, inguinal) requiring general or spinal anesthetic were prospectively randomized into the following groups: Group 1, sequential pneumatic compression devices during surgery and 2 days postoperatively; Group 2, subcutaneous heparin (5000 U q 12 hr) starting 1 hr before surgery and for 7 days postop; Group 3, control group. All patients underwent duplex evaluation of bilateral lower extremity deep venous systems preoperatively and on postoperative Days 1, 3, and 30. In addition, a previously developed predictive DVT incidence indicator, the prognostic index (PI), was calculated for each patient. A total of 137 patients were entered into the study with 29 removed for patient/staff reasons. There were no differences in PI among the three groups at the 0.05 level (ANOVA). The distribution of risk factors for DVT including increased age, body size, hemoglobin (Hb), and colorectal procedures were distributed evenly among the groups. Additional factors such as diabetes, COPD, PVD, immobilization, and cancer were also evenly distributed among the groups. The PI predicted a 20% incidence of DVT. For Groups 1 (n = 25), 2 (n = 38), and 3 (n = 45) no DVTs were detected over the 30 days of study. During the study period, 8 DVTs were detected by duplex evaluation in general surgical patients not in the study (1.5%). In conclusion, in a prospective randomized study using sequential pneumatic compression devices, subcutaneous heparin or no prophylaxis in matched general surgical patients at moderate to high risk for thromboembolism, no DVTs occurred for up to 30 days. Furthermore, neither a PI nor other factors associated with DVT accurately predicted the incidence of DVT in this patient population. Deep vein thrombosis and its sequel, pulmonary embolus, are possibly the greatest threats to recovery after surgical operation. In a randomized, controlled clinical trial in which the 125I-fibrinogen uptake test, Doppler ultrasound, and phlebography were used for diagnosis, it was found that low doses of calcium heparinate administered subcutaneously and sodium pentosan polysulfate intramuscularly were effective in preventing deep vein thrombosis (DVT), postoperatively. The incidence of DVT was as follows: 9% in the group treated with heparinate; 15% in the group treated with sodium pentosan polysulfate; nad 51% in the untreated control group. Ninety patients with venographically proven deep venous thrombosis(DVT) but without clinical signs of pulmonary embolism(PE) were randomized into two different treatment regimens to compare the safety and efficacy of continuous intravenous heparin and oral anticoagulant(AC) treatment versus non-AC treatment. All patients in the two treatment groups were actively mobilized from the day of admission and wore graduated compressing stockings. In the non-AC-group the patients were treated with phenylbutazone for ten days. Treatment with heparin was maintained for 6 days and oral AC treatment was given from the third day and continued for 3 months. Venography was repeated after 30 days. A perfusion-ventilation lung scan was performed on day 1-2, 10 and 60. In fifty-nine patients a revenography was performed, twenty nine in the AC-group and thirty in the non-AC group. For distal veins regression was found in nine and eight respectively (4.4% in favour of AC, 95% confidence limit 27.5% to -18.7%) and in proximal veins regression was found in five and eight, respectively (10.9% in favour of AC, 95% confidence limit 32.0% to -10.1%). No difference in lung scans was found after 10 days (0.8% in favour of AC, 95% confidence limit 21.5% to -19.9%) or after 60 days (3.3% in favour of non-AC treatment, 95% confidence limit 21.8% to -28.5%). In the AC group the incidence of bleeding complications was 8.3%. No side-effects of phenylbutazone was found. The present controlled clinical study demonstrated no effect of AC-treatment on DVT progression in actively mobilized patients wearing graduated compressing stockings when compared to a non-AC treated group receiving analgetic therapy with phenylbutazone. However, the patient population of the study is relatively small with wide confidence intervals for differences between groups. Before more general recommendations can be made, a large scale placebo-controlled study is needed to evaluate the possible effect of AC-treatment in DVT patients, who can be mobilized from the first day. Sixty-one consecutive patients were enrolled in a randomized, controlled trial of thromboprophylaxis with a low molecular weight heparin (Seleparina, CY 216) in major abdominal oncological surgery. Thirty patients received 2 x 3,825 anti-Xa international units of CY 216 subcutaneously on the day of surgery followed by a single daily 3,825 anti-Xa international units injection for 7 days; thirty-one patients did not receive any form of prophylaxis. The occurrence of deep vein thrombosis (DVT) was detected by 125I-labelled fibrinogen leg scan. Postoperative DVT developed in 2 patients in the CY 216 group and in 11 patients in the control group (6.8% vs 35.4%, p < 0.01). Although there was a higher postoperative transfusional requirement in the group receiving CY216 (p < 0.05), the total number of patients transfused was similar in the two groups (14 vs 13). On day 1 after surgery, the two patients who later developed DVT in the CY216 group had plasma anti-Xa activity significantly lower (p < 0.01) than the remaining patients. As a good relationship was found between plasma anti-Xa activity and body weight, adoption of a personalized dosage schedule might improve efficacy of CY 216 prophylaxis. In a prospective randomized double-blind study of 141 patients referred for reconstructive vascular surgery on the abdominal aorta and the lower extremities, placebo was compared to antibiotic prophylaxis. The prophylaxis group received three doses of a combination of methicillin, 2 g and netilmicin, 200 mg. Antibiotic prophylaxis reduced postoperative wound infections as compared to placebo, i.e. 4/69 (5.8%) vs. 12/72, (16.7%) respectively (P = 0.04). No graft infections occurred. Two cases of postoperative septicaemia were seen in the placebo group, none in the antibiotic group. Among different procedures aortic-femoral bypass operations showed the highest wound infection rates. The two treatment groups were comparable with regard to all other postoperative complications registered, including nephro- and ototoxicity. The antibiotic regimen was considered safe, but had only marginal value as prophylaxis in vascular reconstructive surgery on the abdominal aorta and the lower extremities. Oral anticoagulants and aspirin are antithrombotic drugs that are commonly used in patients with vascular disease. We investigated whether either of these treatments prevented more effectively than the other bypass complications after infrainguinal bypass surgery.
                We did a multicentre, randomised, open trial. 2690 patients who had undergone infrainguinal grafting were randomly assigned oral anticoagulants (target international normalised ratio 3.0-4.5, n=1339) or aspirin (80 mg daily, n=1351). We followed up patients for a mean of 21 months. The primary outcome was graft occlusion.
                308 graft occlusions occurred in the oral-anticoagulants group compared with 322 in the aspirin group (hazard ratio 0.95 [95% CI 0.82-1.11]), which suggested no overall advantage for either treatment. Oral anticoagulants were beneficial in patients with vein grafts (0.69 [0.54-0.88]), whereas aspirin had better results for nonvenous grafts (1.26 [1.03-1.55]). The composite outcome of vascular death, myocardial infarction, stroke, or amputation occurred 248 times in the oral-anticoagulants group and 275 times in the aspirin group (0.89 [0.75-1.06]). Patients treated with oral anticoagulants had more major bleeding episodes than those treated with aspirin (108 vs 56; 1.96 [1.42-2.71]).
                Oral anticoagulation was better for the prevention of infrainguinal-vein-graft occlusion and for lowering the rate of ischaemic events. Aspirin was better for the prevention of non-venous graft occlusion, and was associated with fewer bleeding episodes. We describe a case of superior vena caval obstruction (SVCO) due to bronchial carcinoma which was complicated by extensive central venous thrombosis. Partial clot lysis was achieved with thrombolytic agents, but therapy had to be discontinued due to bleeding from the gastrointestinal tract and puncture sites. Clot dissolution was completed using the Amplatz Thrombectomy Device, and the subsequent placement of a Gianturco Z-stent resulted in prolonged symptomatic relief.
There is not enough evidence to make a definitive conclusion about the use of anticoagulant drugs (with or without mechanical devices) for DVT prophylaxis in patients undergoing abdominal aortic surgery.