Noninterventional statistical comparison of BTS and CHEST guidelines for size and severity in primary pneumothorax.

Primary spontaneous pneumothorax (PSP) occurs in apparently healthy young people with an incidence of 12.5 cases per 100 000 per year [1]. Attempts to develop standardised care guidelines for this condition have been severely hampered by a lack of high-quality clinical research into this condition. The American College of Chest Physicians (CHEST) concluded in 2001 that “insufficient data exist…to develop an evidence-based document” and so produced a consensus statement based on expert opinion [2]. Similarly, the British Thoracic Society (BTS) 2010 guidelines are based predominantly on nonanalytical studies and expert opinion [3]. In both documents, the size of the presenting PSP is used to determine initial treatment. A “small” PSP without respiratory compromise is thought not to require intervention, while a “large” PSP has typically been treated either by aspiration or intrapleural drainage. Implicit in these definitions is the belief that large pneumothoraces will not respond well to conservative management. Remarkably, no consensus regarding the definition of PSP severity exists, with CHEST and the BTS each using different arbitrary measurements of the presentation chest radiograph. When these measurements were compared directly to one another, they showed poor correlation [4]. This lack of a clinically useful radiological biomarker for pneumothoraces requiring intervention hinders the development of evidence-based care of this condition. We wished to determine whether the BTS definition of large pneumothorax (>2 cm at the hilum) or CHEST definition (>3 cm from apex to cupola) better predicts the requirement for intercostal chest drain (ICD) insertion.The study was funded by the East Anglian Thoracic Society. M.Z. Nikolić is a Wellcome Trust PhD Programme for Clinicians Fellow at the University of Cambridge. S.J. Marciniak is a Medical Research Council Senior Clinical Fellow. J. Wason is funded by the Cambridge Biomedical Research Centre. Funding information for this article has been deposited with FundRef.This is the final version of the article. It first appeared from the European Respiratory Society via http://dx.doi.org/10.1183/09031936.0011861