Case Studies In Small Animal
Pericardiocentesis was performed at the initial visit to relieve signs referable to chronic cardiac tamponade. A 16-ga Angiocath (over-the-needle catheter) was used. Initially, several small side holes were placed along this catheter using a Number 15 scalpel blade, as shown below. These holes are placed to reduce the incidence of material clogging the catheter.
Nitro was then placed on his left side and a large region on his right chest was clipped and surgically prepped. Lidocaine was infiltrated in the fifth intercostal space, about 1/3 the way up the chest wall. Care was taken to make sure the pleura was infiltrated with lidocaine and we waited five minutes for the lidocaine to work. An extension tube hooked to a three-way stopcock and 60-ml syringe was hooked to the catheter and the catheter, with stylet in place, was advanced through the chest wall. Suction was placed by withdrawing on the syringe and the catheter/stylet was advanced until bloody fluid appeared in the extension tube. The catheter/stylet was advanced another couple of millimeters and then the hub of the stylet was held firmly in place while the catheter was advanced over the stylet and into the pericardial space.
The stylet was then removed and the extension tube disconnected from the stylet and connected to the catheter hub. Fluid was then withdrawn. Initially, a small amount was withdrawn and placed in a tube that contained thrombin (FDP tube) to see if it would clot. It didn't which confirmed that we were in the pericardial space, not a cardiac chamber. Alternatively, we could have placed the fluid in a plain glass tube and waited for 10 minutes to see if it would clot (my personal record is 11 minutes).
Once we were sure that we were in the pericardial space, we withdrew as much fluid as possible. A total of approximately 900 ml was removed.
Here is the ECG immediately after the pericardiocentesis. Notice that the complexes are larger, the electrical alternans is gone, and the heart rate is slower with a sinus arrhythmia.
The ECG was recorded at a calibration of 1 cm = 1 mV and at 50 mm/sec.
©Mark D. Kittleson, D.V.M., Ph.D. All rights reserved.