Stratifying fibrinolytic dosing in pediatric parapneumonic effusion based on ultrasound grade correlation

Complicated pleural effusion prolongs the hospital course of pneumonia. Chest tube placement with instillation of fibrinolytic medication allows efficient drain output and decreases hospital stay.

To evaluate experience with lower fibrinolytic dose for parapneumonic effusions and to assess potential dose stratification based on a simple ultrasound grading system.

We retrospectively reviewed the medical record to identify children and young adults who received fibrinolytic therapy for parapneumonic effusion and had chest tube placement by an interventional radiology service at a single children's hospital. We assessed tissue plasminogen activator (tPA) dosing and treatment duration, as well as the need for a second pleural procedure or surgical drainage. Diagnostic US images were classified as showing less than 50% pleural echogenicity (grade 1) or greater than 50% pleural echogenicity (grade 2) and were correlated with clinical parameters.

Of 32 patients with parapneumonic effusion, all except one received at least some 1-mg tPA doses. Dosing was solely 1-mg tPA in 81% of subjects; 19% of subjects also received 2-mg tPA doses. Mean fibrinolytic duration was 3.1 days for grade 1 effusions compared to 5.4 days for grade 2 effusions. A second pleural procedure was required in 15.6% of children. Pleural drainage with fibrinolytic therapy was successful in 97%; only one child required surgical drainage. Grade 2 US differed significantly from grade 1 US, with grade 2 occurring in younger patients (P < 0.0001), smaller patients (P < 0.0001), those needing a second procedure (P = 0.001), those with positive pleural culture or polymerase chain reaction test (P = 0.006), and those with longer treatment duration (P = 0.03).

A lower 1-mg dosing regimen of tissue plasminogen activator was effective in all children with less complex (grade 1 US imaging) parapneumonic effusions. Grade 2 US images correlated with younger and smaller children, presence of a pleural organism, and longer or more complicated chest tube duration.