Data collection
Data were retrospectively extracted from medical charts by three
investigators (M.T., F.L. and P.D.). Baseline data included medical
history, age, main complaints and clinical findings at hospital
admission. Tachycardia was defined according to the age based on the
following thresholds: 180 beat per minute (bpm) for infants, and 160 bpm
for children aged 1-16-years. The increased work of breathing was
documented as per medical notes, based on a subjective assessment by the
treating physician (no scale measurement).
Data collected during the hospital stay included the use of at least one
dose of corticosteroid (prednisone or methylprednisolone) as part of the
management of the pleural effusion, the use of respiratory support
techniques (high-flow oxygen therapy, noninvasive ventilation,
mechanical ventilation), the number of chest imaging exams and the use
of painkillers. We also collected data to characterize the pleural
effusion, including the time of diagnosis, the presence of fibrin in the
effusion (according to the chest ultrasound protocol), the time and type
(needle thoracocentesis, chest tube) of evacuation (if any), the
duration of drainage (if any), the total volume drained, the use of
intrapleural fibrinolysis, as well as the leucocyte count of the pleural
effusion. We also collected the total duration of fever (defined as a
temperature ≥ 38°C), the highest C-reactive protein (CRP) level as well
as the highest leukocyte count. Finally, we recorded the duration of the
hospital stay.