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Alan Benheim

 John North

39 Pericardiocentesis

A. Definitions

1. Pericardium

a. A double layer of mesothelial lining surrounding the

heart, consisting of the visceral pericardium on the

epicardial surface and the parietal pericardium as an

outer layer

b. Between the two layers, there is normally a small

amount of pericardial fluid (typically <5 mL for a

neonate) that is thought to reduce friction.

2. Pneumopericardium

a. Collection of air in the pericardial space

3. Pericardial effusion

a. Accumulation of excess fluid in the pericardial

space

4. Pericardiocentesis

a. A procedure to remove air or excess fluid from the

pericardial space, usually through a needle, small

cannula, or drainage catheter

5. Pericardial drain

a. A catheter or other drainage device left in place to

allow intermittent or continuous evacuation of air or

fluid from the pericardial space

b. Placed in select situations with recurring accumulation of air or fluid in the pericardial space

6. Tamponade

a. Clinical condition with limited cardiac output

because of external restriction of expansion of the

heart, preventing normal cardiac filling, resulting in

a decreased stroke volume and impaired cardiac

output

b. May be caused by

(1) Fluid or air in the pericardial space

(2) Abnormalities of the pericardium (restrictive or

constrictive)

(3) Increased intrathoracic pressure associated with

obstructive airway lung disease or tension pneumothorax

7. Pulsus paradoxus (Fig. 39.1)

a. Respiratory variation in blood pressure, with a

decrease in systolic blood pressure during spontaneous inspiration. (During positive-pressure ventilation, this is reversed, with a rise in systolic pressure

during inspiration.)

b. This finding occurs during tamponade.

B. Purpose

1. To evacuate air to relieve cardiac tamponade

2. To evacuate fluid to relieve cardiac tamponade

3. To obtain fluid for diagnostic studies

C. Background (See also A)

1. The heart lies within a closed space, covered by the

pericardium. The pericardial space lies between

the two layers of the pericardium. If the pericardial

space fills with excess fluid or if air accumulates, the

heart has less space available, and the pressure within

the pericardium increases. Increased intrapericardial

pressure restricts venous return and impairs cardiac filling. The decrease in venous return and cardiac filling

results in a reduced cardiac output. This clinical situation is known as cardiac tamponade (1–5).

2. Neonates are at increased risk for cardiac tamponade

when there is

a. Accumulation of air dissecting into the pericardium

from the respiratory system (Fig. 39.2) (4–7)

b. Pericardial fluid accumulation due to perforation or

transudate from umbilical or central venous catheter (Figs. 32.15, 39.3) (1,8–12)

c. Cannulation for extracorporeal membrane oxygenation (13,14)

d. Cardiac catheterization, either diagnostic or therapeutic (15)

e. Postoperative pericardial hemorrhage following cardiac surgery (2,16)

f. Postpericardiotomy syndrome, typically 1 to 3 weeks

after cardiac surgery (2,16,17)

g. Pericardial effusion as part of generalized edema/

hydrops (3,16)

h. Pericardial effusions due to infectious or autoimmune causes. (These are less common in neonates

than in older children.)