The second leading cause of iatrogenic pneumothorax is central cannulation, due to the increasing number of patients requiring intensive care.
Inadvertent subclavian arterial puncture is a relatively common complication of subclavian venepuncture.[14] The overall reported incidence is in the range of 1-13% with 2-5% being typical. This incidence increases to about 40% if multiple attempts are made. Thoracentesis is probably the third leading cause of iatrogenic pneumothorax .This can be reduced if it is done under ultrasound guidance. In a study analyzing outcomes of 418 invasive procedures, the incidence of iatrogenic pneumothorax was 13% for computed tomography (CT)-guided transthoracic fine needle aspiration (TFNA), 7.1% for pleural biopsy, 16.6% for transbronchial biopsy, 7.1% for fluoroscopy guided TFNA, and 1.5% for thoracentesis.[15] Mechanical ventilation causing pneumothorax has come down because with newer ventilatory mode it is possible to ventilate patients with lower peak pressures and lower mean airway pressure. Other procedures which may be responsible are, transpleural and transbronchial lung biopsies, cardiopulmonary resuscitation, thoracic acupuncture,[16] and in intravenous drug abuser using neck veins.