Question

At what level must you do a thoracentesis when pleural effusion is seen on a chest x-ray?

1) At the level of the diaphragm
2) At the level of the mid-axillary line
3) At the level of the clavicle
4) At the level of the sternum

Answer 1

A thoracentesis should be done at the level of the mid-axillary line, typically between the 5th and 7th intercostal spaces, to safely address a pleural effusion. The correct option is 2.

Step-by-step explanation:

When performing a thoracentesis to interventionally address a pleural effusion, as seen on a chest x-ray, the procedure should be conducted at the level of the mid-axillary line, typically between the 5th and 7th intercostal spaces to avoid injury to the diaphragm and other vital structures.

The pleural cavity is the potential space between the two pleurae (visceral and parietal) of the lungs. The proper approach to thoracentesis involves identifying the most appropriate site which is safe and allows for maximum fluid removal. Conducting the procedure at the level of the diaphragm, clavicle, or sternum would not be appropriate due to the risk of damaging underlying organs or inducing complications.

Standard practice recommends the use of ultrasound guidance to identify the best site for needle insertion. Hence, 2 is the correct option.