Pleural effusion puncture site

Pleural fluid puncture is a therapeutic and diagnostic technique for extracting pleural fluid and related gas from patients with pleural effusion and pneumothorax. So where is the puncture site for pleural effusion, what is the specific operation procedure for pleural effusion puncture, and what should be paid attention to? The following article will provide detailed answers to the above questions for you.

Body Position

The patient sits facing the back of a chair, places both forearms on the back of the chair, and rests his forehead on his forearms. Patients who cannot get up can take a semi-sitting position with their forearms raised and held on the pillow.

Select the puncture point

The puncture point is chosen at the site where the percussion sound is most obvious. When there is a lot of pleural effusion, the puncture point is usually between the scapular line or the 7th and 8th intercostal space on the posterior axillary line. Sometimes the 6th and 7th intercostal space on the mid-axillary line or the 5th intercostal space on the anterior axillary line is also chosen as the puncture point. Loculated effusions can be identified by x-ray or ultrasonography, and the puncture site is marked on the skin with a cotton swab dipped in gentian violet or other marking pen.

Operating Procedure

(1) Routine skin disinfection: Disinfect the skin around the puncture point, about 15 cm in diameter, twice.

(2) Open the disposable thoracentesis kit, put on sterile gloves, cover with a sterile towel, check the contents of the thoracentesis kit, and pay attention to whether the thoracentesis needle is unobstructed after being connected to the syringe for fluid extraction. Also check for any air leaks.

(3) The assistant helps to check and open the 2% lidocaine ampoule. The operator uses a 5ml syringe to draw 2-3ml of 2% lidocaine and performs local invasive anesthesia from the epidermis to the pleural wall at the puncture site. If the puncture point is the scapular line or the posterior axillary line, insert the anesthetic needle along the upper edge of the lower rib between the ribs. If the puncture point is at the midaxillary line or the anterior axillary line, insert the needle between the two ribs.

(4) Connect the thoracentesis needle to the syringe for fluid extraction and close the switch between the two to ensure that they are tightly closed and leak-proof. The operator fixes the skin at the puncture site with the index and middle fingers of one hand, and holds the puncture needle with the other hand and slowly inserts it along the anesthesia site. When the sudden resistance sensation at the needle tip disappears, turn on the switch to connect it with the chest cavity to draw fluid. The assistant uses hemostatic forceps (or spare forceps in the thoracotomy kit) to help fix the puncture needle to prevent it from piercing too deep and damaging the lung tissue. After the syringe is full, turn off the switch (some syringes used to draw fluid from thoracentesis bags have a one-way valve design at the front end, so the switch can also be left open, depending on the specific situation) to drain the liquid into the drainage bag and count the amount of fluid drawn.

(5) After the aspiration is completed, remove the puncture needle, disinfect the area, cover with sterile gauze, apply slight pressure for a moment, and secure with tape.