Validity of lung ultrasound to rule out iatrogenic pneumothorax performed by pulmonologists without experience in this procedure

Abstract

Introduction: Ultrasonography has been shown to be a useful tool for diagnosing pneumothorax in the hands of experts. After performing bronchopleural procedures, the recommendation is to perform chest radiography to rule out complications. Our objective was to determine the validity of lung ultrasound, conducted by pulmonologists without experience in this procedure, to tule out pneumothorax after invasive procedures.

Material and methods: Our prospective observational study consecutively included patients who underwent transbronchial lung biopsy (TBLB), therapeutic thoracentesis (TT) and/or transparietal pleural biopsies (PB) for whom subsequent chest radiography to rule out complications was indicated. In all cases, the same pulmonologist who performed the technique performed an ultrasound immediately after the procedure. A diagnosis of pneumothorax was considered in the presence of a lung point or the combination of the following signs: absence of pleural sliding, absence of B-lines and presence of the "barcode" sign.

Results: We included 275 procedures (149 TBLBs, 36 BPs, 90 TTs), which resulted in 14 (5.1%) iatrogenic pneumothoraxes. Ultrasonography presented a sensitivity of 78.5%, a specificity of 85% and positive and negative predictive value of 22% and 98.6%, respectively. Ultrasonography did not help detect the presence of 3 pneumothoraxes, one of which required chest drainage, but adequately diagnosed 2 pneumothoraxes that were not identified in the initial radiography.

Conclusions: Lung ultrasound performed by pulmonologists at the start of their training helps rule out pneumothorax with a negative predictive value of 98.6%, thereby avoiding unnecessary radiographic control studies in a considerable number of cases.

Keywords: Bronchopleural techniques; Ecografía torácica; Formación; Lung ultrasound; Negative predictive value; Neumotórax; Pneumothorax; Training; Técnicas broncopleurales; Valor predictivo negative.