Pericardiocentesis (PCC) is a medical procedure where fluid is aspirated from the pericardium.
The pericardium is a fibrous sac surrounding the heart composed of two layers: an inner visceral pericardium and an outer parietal pericardium.
The area between these two layers is known as the pericardial space and normally contains 15 to 50 mL of serous fluid.
This fluid protects the heart by serving as a shock absorber and lubricates to the heart during contraction.
The pericardium allows it to accommodate a small amount of extra fluid, roughly 80 to 120 mL, in the acute setting.
Once a critical volume is reached, even small amounts of extra fluid can rapidly increase pressure within the pericardium.
Such increased pressure can significantly hinder the ability of the heart to contract, leading to cardiac tamponade.
Slow accumulation of fluid over weeks to months allows thebpericardial sac can tolerate several liters of additional fluid without substantially hindering the ability of the heart to pump.
Indications for performing pericardiocentesis: therapeutic as for treating tamponade, and those that are diagnostic as fornpericardial fluid analysis.
Pericardiocentesis can be used to diagnose and treat cardiac tamponade.
Cardiac tamponade is a medical emergency, as it can critically decrease the amount of blood that is pumped from the heart, causing obstructive shock, which can be lethal.
The removal of the excess fluid by pericarp reverses this process, and is often the first treatment for cardiac tamponade due to its speed.
Pericardiocentesis can also relieve the symptoms of pericarditis causing inflammation still causes compression of the heart, and removal of some of the pericardialmfluid reduces pressure on the heart.
Pericardiocentesis can also be used to analyze the fluid surrounding the heart in the pericardial sac.
Fluid may be analyzed to differentiate a number of conditions, including:
infection cancer autoimmune conditions, such as lupus and rheumatoid arthritis
There are no absolute contraindications to pericardiocentesis in emergency situations where a patient is hemodynamically unstable.
Pericardiocentesis is a one-off procedure, which may not be appropriate for long-term drainage.
In cases where longer term drainage is needed, a pericardial window can be created, and involves the removal of a section of the pericardium, and the placement of a chest tube.
Pericardiocentesis is not appropriate if cardiac tamponade is associated with aortic dissection, or for the diagnosis of minor pericardial effusion.
Other relative contraindications include coagulopathies, thrombocytopenia, myocardial rupture, severe pulmonary hypertension, prior thoracoabdominal surgery, prosthetic heart valves, pacemakers and other cardiac devices, inadequate visualization of the effusion on ultrasound during the procedure, and situations in which more appropriate treatment options are available.
The patient undergoing pericardiocentesis is positioned supine with the head of the bed raised between a 30- and 60-degree angle.
This position places the heart in proximity to the chest wall for easier insertion of the needle into the pericardial sac.
A local anaesthetic is applied, and a large needle is inserted through the skin of the chest into the pericardium, and the fluid pericardial effusion is aspirated into a syringe.
A drain can be placed for continuous access.
There are multiple locations that pericardiocentesis can be performed without puncturing the lungs.
The infrasternal angle called subxiphoid approach: The needle is inserted at an angle between 30 and 45 degrees to the chest 1 cm inferior to the left xiphocostal angle.
The parasternal approach: through the 5th or 6th intercostal space at the left sternal border at the cardiac notch of the left lung.
The needle is inserted at an angle of 90 degrees to the chest.
With the routine use of ultrasound guidance, the apical approach is becoming more widely used.
The apical approach: The needle is inserted at the level of the cardiac apex, usually between the 5th-7th intercostal space.
The needle is advanced directly over the superior aspect of the rib to avoid the neurovascular bundle and aimed toward the right shoulder.
Pericardiocentesis is performed with ultrasound guidance, allowing the assessment of the location of the pericardial effusion and identify adjacent structures.
Agitated saline is injected and visualized sonographically to confirm the needle placement in the pericardium.
Pericardiocentesis can be performed using computed tomography (CT) imaging in cases of complex or loculated effusions.
Blind pericardiocentesis can be performed in emergency settings when ultrasound is not available and typically utilizes a subxiphoid approach.
To prevent perforation of the heart, electrocardiographic (ECG) monitoring using an alligator clip to attach an ECG lead to the needle.
Fewer than 1.5% of patients experience complications from pericardiocentesis.
The most common complications are lacerations of coronary arteries, and puncture of the left ventricle.
Echocardiograms can help to identify complications.