OBJECTIVES: Iatrogenic pneumothorax occurs when air or gas becomes present in the pleural cavity following medical treatment. Besides subjecting the patient to unnecessary health risks, iatrogenic pneumothorax leads to an increased amount of healthcare resources including observed through patient cost, length of stay, and inpatient mortality. This research aims to quantify the incremental effects of iatrogenic pneumothorax on these three outcomes. METHODS: Discharge records from Premier’s Perspective database of US inpatients who underwent inpatient pulmonary surgery and were discharged in 2007 were examined. The definition of iatrogenic pneumothorax consistent with ICD-9-CM code 512.1 was used to classify patients. Chi-square tests were used to detect differences between iatrogenic pneumothorax patients and non- iatrogenic pneumothorax patients for three outcomes. Multivariable regression models were used to obtain more precise estimates of the incremental effects of iatrogenic pneumothorax on outcomes while controlling for comorbidities, demographic variables and the patient’s primary treatment. RESULTS: A total of 112,827 patients were analyzed (8,482 with iatrogenic pneumothorax). Chi-square tests demonstrated that patients with iatrogenic pneumothorax were older (p<0.0001), had lower hospital costs (p<0.0001), a shorter length of stay (p<.0001), and lower mortality rate (p<.0001). Log linear modeling demonstrated iatrogenic pneumothorax increases patient costs by 10.49% (95%CI: 8.76%-12.23%). Negative binomial models showed iatrogenic pneumothorax increases patients length of stay by 8.01% (95%CI:6.21%-9.82%), while no difference was found with respect to mortality. CONCLUSIONS: The incremental effects of iatrogenic pneumothorax are shown to significantly increase patient costs and length of stay but not inpatient mortality.