Circulation Skills 6:
Pericardiocentesis
Penetrating trauma to the chest should alert the team to the possible presence or development of cardiac tamponade. Beck's triad (muffled heart sounds, distended neck veins, and hypotension) is usually present if the patient is not also hypovolemic. It is not always present. Ultrasound makes the diagnosis quick and easy.
A Seldinger technique pericardiocentesis set (Wood set by Cook Critical Care Co.)
Any patient in shock should undergo ultrasound by the emergency care team. If a pericardial effusion is seen and cardiac tamponade seems to be the correct diagnosis, do the following:
- Insert the exploring needle from a percutaneous pericardiocentesis set next to the xiphoid process under the left costal margin directed toward the patient’s left shoulder. Attach a 35 mL syringe to the needle.
- When blood returns through the exploring needle, extract a few mL and reapply the ultrasound probe. Inject the blood back into the chest rapidly. The turbulence produced will be seen on ultrasound "lighting up" the pericardial fluid and not appearing in the ventricles, positively identifying the position of the needle.
- If the needle is in the pericardial sac, remove 35 mL of blood. This will restore stroke volume to near normal, and the patient will improve.
- Insert the guidewire of the set into the pericardial sac through the needle. Before removing the needle, make a stab incision with the #11 blade on the needle through the fascial layers of the abdomen
- Pass the dilator of the set over the wire into the pericardial sac. Remove the dilator and pass the pigtail catheter of the set over the wire into the pericardial sac. Remove the wire. Attach a stopcock and syringe for repeated aspirations of blood.
Obviously, this procedure takes time. Removing 35 mL immediately buys the time necessary to get this done.
When an ultrasound machine is not available, the emergency physician should use pericardiocentesis to establish the diagnosis of cardiac tamponade. The classic Beck’s Triad, unfortunately, is not always present. A significant mechanism of injury (penetrating chest wound or blunt chest trauma), probability of a myocardial infarction about 3 or 4 days previously, an illness suggestive of pericarditiis, a probable aortic dissection, and bigeminy on ECG are other clues. A chest x-ray may reveal a globular appearance of the cardiac shadow. If the needle touches the myocardium, PVCs will result, and you may feel the heart beating against the needle.
Pericardiocentesis is a temporizing
measure. Repeated aspirations may be necessary before definitive
surgery can take place. If the pericardiocentesis attempt fails to
return blood, the blood has most likely clotted. If the patient is in
mortal distress with loss of consciousness, a thoracotomy would be
needed, allowing the performance of an internal pericardiocentesis. See Vol
II—Circ Skills 4 Emergency Thoracotomy.
References
Spodick DH. The technique of pericardiocentesis. J Crit Illness. 1987;2(7):91-96.
Plummer D, Brunette D, Asinger R, Ruiz E. Emergency department echocardiography improves outcome in penetrating cardiac injury. Ann Emerg Med. 1992;21(6):709-712.