NONFATAL PULMONARY EMBOLISM IN THE HIGH-RISK TRAUMA PATIENT MANAGED IN ORTHOPAEDIC WARD: DO RISKS WITHOUT TYPICAL CLINICAL SYMPTOMS JUSTIFY AGGRESSIVE SCREENING?

Abstract

Background: The standard diagnostic approach in patients suspected of having pulmonary embolism starts with D-dimer and perfusion-ventilation lung scanning. If the resulting scan is not diagnostic, pulmonary angiography will perform.

Aims: This study evaluates the effectiveness of D-dimer as a screening tool for Pulmonary Embolism (PE) and to determine the accuracy and potential clinical utility of VQ scan in the diagnosis of pulmonary embolism in orthopaedic trauma patient.

Methods: We retrospectively reviewed 757 consecutive trauma admissions involving lower extremity and spinal injuries over 12 months and identified 20 patients with symptoms mimicking PE, without typical clinical symptoms, which underwent rotten investigations for PE (ABG, Blood test, D dimer, Chest X-ray and VQ scan).

Plasma D-dimer levels were measured as a prerequisite test in all patients before undergoing VQ scan to confirm the absence of PE. All patients had either mechanical, such as foot pumps, or chemical DVT prophylaxis.

Results: The mean age was 65 (ranging from 45–88) years, there were 11 female and 9 male. D-dimer levels in the postoperative or post traumatic period were elevated. Mean value was 3.63 (sd=2.72, range 0.60–14.34), Comparing D-dimer levels between those treated operatively (14 patients) and those treated conservatively (6 patients) we found that both groups displayed the same trend; however levels were higher following surgery.

The classical triad of dyspnoea, pleuritic chest pain and haemoptysis occurred in only 2 patients. Signs of DVT were present in 3 patients. The electrocardiographs were normal in only 4 patients, though changes particularly suggestive of PE (S1Q3T3, Right bundle branch block or right heart strains) were absent in all of the patients. Chest X-ray changes were of limited value. None showed any of the supposedly characteristic changes.

All of the patients had a VQ scan were started on chemical treatment for PE and non of them had definite PE, 12 the patients had probable PE Those patient with probable scan were not subsequently given anticoagulants owing to their medical conditions

Conclusion: The D-dimer level is never normal (< 0.5mg/l), following total trauma, and so cannot exclude a DVT or PE. The level it raises to is indistinguishable form that seen in the population with a PE and so cannot identify those patients in whom further investigation is warranted. VQ scan is not a definitive diagnosis we should rely more and more on a CT Angiography scan for the diagnosis of PE in this group of patients. This should be organised by medical team, especially with shortening of training time, to avoid wasting of resources and time which are of paramount. Requesting a D-dimer test in this population wastes time and resources and is of no benefit