Conservative versus invasive management of secondary spontaneous pneumothorax: a retrospective cohort study.

Aim Hospitalization, often with intervention, is the recommended management algorithm by multiple international respiratory societies for management of a secondary spontaneous pneumothorax (SSP). Over recent years we adopted a conservative approach to SSPs. We undertook a retrospective cohort study of SSP to establish the safety profile of a conservative approach for these previously unstudied patients. Methods We reviewed all cases of SSP presenting to our institution from 2012 to 2019 using the 2010 British Thoracic Society definition of an SSP. Age, gender, smoking status, underlying lung disease, pneumothorax size estimate (using the Collins method), nature of intervention, inpatient duration, and any additional complications were recorded. The χ2-test and Mann-Whitney U-test were used for comparison of categorical variables and categorical/continuous variables, respectively. Results Eighty-two cases were included in the final analysis. Of them, 64 had an interpleural distance at the hilum of 1cm or greater, meeting British Thoracic Society criteria for a pleural intervention. Of these 64 patients, 25 (39%) were managed conservatively. No patient managed conservatively required a subsequent intervention. When stratified for conservative or invasive management, there was no significant difference in age, gender, smoking status, or presence of underlying lung disease between the groups. There was a significant difference in size of the pneumothorax with conservative management having smaller pneumothoraces (37% versus 54%, P < 0.001) and a shorter inpatient stay (conservative, 7.9 days; intercostal catheter, 9 days; P = 0.004). Conclusion We have demonstrated success with conservative management of SSPs where a significant proportion of them met accepted criteria for a pleural intervention.