No abstract

Objective: To determine the incidence of venous thromboembolism (VTE), comprising deep vein thrombosis (DVT) and pulmonary embolism (PE), in a well defined urban community broadly representative of the Australian population in terms of age, sex and ethnic distribution. Design, setting and participants: A prospective, community‐based study conducted over a 13‐month period from 1 October 2003 to 31 October 2004. People in a population of 151 923 permanent residents of north‐eastern metropolitan Perth, Western Australia, who developed VTE during the study period were identified prospectively and retrospectively through multiple overlapping sources. Main outcome measure: Number of cases of symptomatic, objectively verified DVT and PE. Results: 137 patients had 140 VTE events (87 DVT and 53 PE). The crude annual incidence per 1000 residents was 0.83 (95% CI, 0.69–0.97) for VTE, 0.52 (95% CI, 0.41–0.63) for DVT, and 0.31 (95% CI, 0.22–0.40) for PE. The annual incidence per 1000 residents after age adjustment to the World Health Organization World Standard Population was 0.57 (95% CI, 0.47–0.67) for VTE, 0.35 (95% CI, 0.26–0.44) for DVT, and 0.21 (95% CI, 0.14–0.28) for PE. Conclusion: If the crude annual incidence of VTE in this area of metropolitan Perth is externally valid, then VTE affects about 17 000 Australians annually. Future studies of trends in VTE incidence will be needed to measure the effectiveness of VTE prevention strategies.

Venous thromboembolism (VTE) affects 1–2 per 1000 people in the general population each year. Clinical diagnosis of deep venous thrombosis (DVT) is unreliable, and must be confirmed by compression ultrasonography or venography. A low clinical pretest probability of DVT and negative D‐dimer result reliably exclude the diagnosis, with no need for diagnostic imaging. Initial treatment of DVT is with low‐molecular‐weight heparin or unfractionated heparin for at least 5 days, followed by warfarin (target INR, 2.0–3.0) for at least 3 months. A vena cava filter is indicated in patients who are ineligible for anticoagulant therapy or who experience embolism despite therapeutic anticoagulation. Thrombolysis or surgical embolectomy may be used as a limb‐saving measure in patients with extensive proximal DVT and circulatory compromise that threatens the viability of the leg. Decisions regarding the optimal duration of anticoagulation to prevent recurrent VTE should be individualised and balance the risk of recurrence if warfarin is stopped against the risk of major bleeding and inconvenience of continuing treatment. The risk of recurrence is highest in people with recurrent unprovoked DVT or chronic predisposing factors (eg, cancer) who require indefinite anticoagulant treatment.

Pulmonary embolism (PE) affects 0.5–1 per 1000 people in the general population each year, and is one of the most common preventable causes of death among hospitalised patients. The clinical diagnosis of PE is unreliable and must be confirmed objectively with ventilation perfusion scanning or computed tomography pulmonary angiography. The diagnosis of PE can be reliably excluded, without the need for diagnostic imaging, if the clinical pretest probability for PE is low and the D‐dimer assay result is negative. The initial treatment of PE is low‐molecular‐weight heparin or unfractionated heparin for at least 5 days, followed by warfarin (target international normalised ratio [INR], 2.0–3.0) for at least 3–6 months. Patients with a high clinical pretest probability of PE should commence treatment immediately while awaiting the results of the diagnostic work‐up. Thrombolysis is indicated for patients with objectively confirmed PE who are haemodynamically unstable. Percutaneous transcatheter or surgical embolectomy may be life‐saving in patients ineligible for, or unresponsive to, thrombolytic therapy. Unresolved issues in the management of venous thromboembolism include the roles of thrombophilia testing, thrombolysis for the treatment of stable PE patients who present with right ventricular dysfunction, and new anticoagulants; and the duration of anticoagulation for first unprovoked venous thromboembolism.

Preoperative anaemia affects 13.9% of patients undergoing elective major surgery. The most common causes are iron deficiency and chronic diseases. The cause was unexplained in 25.5% of patients with anaemia. The prevalence of anaemia in different surgical specialties may have implications on the approach to screening, particularly in resource-limited areas.