In a child with a 24% pneumothorax, the correct chest-tube insertion location is which of the following?

• A. Fifth intercostal space in the midclavicular line
• B. Second intercostal space in the midaxillary line
• C. Fourth intercostal space in the midaxillary line
• D. Second intercostal space in the midclavicular line

Answer: (D)

Air rises to the apex of the pleural space, so draining a pneumothorax most quickly and effectively comes from placing the tube at the lung apex. In a child, the apical pleural space is accessed best at the second intercostal space along the midclavicular line, which places the tube directly into the area where air accumulates and allows rapid re-expansion of the lung. This location also keeps the entry high enough to minimize risk to abdominal organs and to the diaphragm as the chest is smaller in a child. In contrast, lower or more lateral sites (such as the midaxillary line lower interspaces) drain the lateral/precentral pleural space and are less optimal for evacuating apical air, and they do not address the pneumothorax as promptly. Therefore, the apical approach at the second intercostal space in the midclavicular line is the best choice for chest-tube insertion in this setting.