pulmonary disorders
How To Do Thoracentesis
Step by Step Description of Thoracentesis
Confirm the extent of the pleural effusion by chest percussion and consider an imaging study; bedside ultrasonography is recommended both to reduce the risk of pneumothorax and to increase the success of the procedure ( References ). Select a needle insertion point in the mid-scapular line at the upper border of the rib one intercostal space below the top of the effusion. Mark the insertion point and prepare the area with a skin cleansing agent such aschlorhexidineand apply a sterile drape while wearing sterile gloves. Using a 25-gauge needle, place a wheal of local anesthetic over the insertion point. Switch to a larger (20- or 22-gauge) needle and inject anesthetic progressively deeper until reaching the parietal pleura, which should be infiltrated the most because it is very sensitive. Continue advancing the needle until pleural fluid is aspirated and note the depth of the needle at which this occurs. Attach a large-bore (16- to 19-gauge) thoracentesis needle-catheter device to a 3-way stopcock, place a 30- to 50-mL syringe on one port of the stopcock and attach drainage tubing to the other port. Insert the needle along the upper border of the rib while aspirating and advance it into the effusion. When fluid or blood is aspirated, insert the catheter over the needle into the pleural space and withdraw the needle, leaving the catheter in the pleural space. While preparing to insert the catheter, cover the needle opening during inspiration to prevent entry of air into the pleural space. Withdraw 30 mL of fluid into the syringe and place the fluid in appropriate tubes and bottles for testing. If a larger amount of fluid is to be drained, turn the stopcock and allow fluid to drain into a collection bag or bottle. Alternatively, aspirate fluid using the syringe, taking care to periodically release pressure on the plunger. If a large amount of fluid (eg, > 500 mL) is withdrawn, monitor patient symptoms and blood pressure and stop drainage if the patient develops chest pain, dyspnea, or hypotension. Coughing is normal and represents lung re-expansion. Some clinicians recommend withdrawing no more than 1.5 L in 24 hours, although there is little evidence that the risk of re-expansion pulmonary edema is directly proportional to the volume of fluid removed ( References ). Animal data suggest that rapidly draining long-standing effusions may lead to re-expansion pulmonary edema by decreasing surfactant. It may be reasonable for experienced operators to completely drain effusions in one procedure in properly monitored patients. Remove the catheter while patient is holding breath or expiring. Apply a sterile dressing to the insertion site. 