Analysis Of Pleural Effusion In Patients With Pulmonary Embolism

Objective:This study aimed to (ⅰ) determine the incidence, side, cytological and biochemical characteristics of pleural effusions in patients with pulmonary emboli(PE); and (ⅱ) determine if there is arelationship between development of pleural effusions in PE and the location of emboli and number ofpulmonary arteries involved.Methods:A total of 523 patients with clinically suspected PE were enrolled and treated in ShandongProvincial Hospital Affiliated to Shandong University and Mount Yantai hospital from 2005 to 2014.All the patients were used CT pulmonary angiograms (CTPA)as first-lineimaging investigation for PE.Compare size, side, biochemical andcytological characteristics of pleural effusions between 143 patients with PE and pleural effusions and 138 patients with pleural effusions who were treated for cor pulmanale,valvular heart disease coronary heart disease, and other pulmonary diseases andin all of them PE was excluded.Results:(1)Of 523patients with clinically suspected PE,251 patients (48%) had the evidence ofpulmonary emboli (159 had both centraland peripheral emboli and 92 peripheral clots only). Emboli were bilateral in 162 cases and unilateralin 89 cases. Pleural effusion was found in 112 (45%) patients with PE. Patients with PE were more likely to have a pleural effusion (OR 2.2 (95%CI:1.1-4.7), P<0.05) than those without PE.However, the effusions were generally very small.(2)Of 112 patients with pleural effusions and PE,21 (9.55%)had bilateral pleuraleffusions,51 (23.18%)patients had pleural effusion on the right side, and 40 (18.18%) had left-sidedpleural effusion.75 (3.18%) had mildpleural effusions,30 (13.64%)had moderate pleural effusions and 7 (3.18%) had large.66 (30.00%) had yellowishcolored pleural effusions,43 (19.55%) had haemorrhagicpleural effusion, and 3(1.36%) had transparent pleural effusion. Values of the total protein in pleural effusionsvaried in the interval 45.70 ± 7.25 g/1.,109 patients had LDH an effusion/sera ratiobigger than 0.6, and 3 patient had an LDH effusion/sera ratio< 0.6. 54 patients (24.55%) had neutrophilcells,36 (16.36%) had lymphocytes, and 16(7.27%) had eosinophil cell.3 patient (1.64%) had a negativecytological finding.(3)Most (83%) of the effusions were found on the same side as the emboli. The location of emboli andnumber of pulmonary arteries involved did not predict the presence of pleural effusions.Conclusions:Pleural effusion is common in patients with pulmonary emboli. These effusions are usually small, mostly unilateral, often but not alwayshaemorrhagic. They are always exudates with a predomination of neutrofil cells. Clinicians should thereforehave a high threshold of suspicion in pleural effusions to embolicdiseases without excluding alternative diagnoses.