Professional and Linguistic Assessments Board (PLAB) Practice Exam

Chest tube placement is typically in which anatomical location?

1. 5th intercostal space, mid-axillary line

2. 4th intercostal space, anterior-axillary line

3. 3rd intercostal space, in the midline

4. 6th intercostal space, posterior-axillary line

The correct answer is: 4th intercostal space, anterior-axillary line

Chest tube placement is generally recommended at the 5th intercostal space in the mid-axillary line. This location is optimal for safe and effective drainage of pleural fluid or air, as it allows for access to the pleural space while minimizing the risk of injury to the underlying structures, such as the lungs and major blood vessels. The mid-axillary line serves as a helpful anatomical landmark, representing an area where the rib cage is situated in a way that reduces the likelihood of damaging the intercostal neurovascular bundle, which runs along the lower edge of each rib. Placing the chest tube in this location allows for better drainage while ensuring that the tube can be secured effectively without causing unnecessary complications. In contrast, the 4th intercostal space at the anterior-axillary line, while used in some practices, may not provide the same efficacy for drainage as the mid-axillary option. The other choices, including the 3rd and 6th intercostal spaces, also carry certain risks, such as compromising the lung or missing the pleural space entirely. Therefore, understanding the anatomical considerations is critical for proper chest tube placement.