B4.070 Prework 2: Pericardial Effusion/Tamponade

Question 1

normal intra pericardial pressure (IPP)

Answer 1

below intra cardiac pressure

with respiration, has the same changes as intra thoracic and intra cardiac pressures

Question 2

does IPP influence cardiac filling?

Answer 2

not in normal circumstances

Question 3

when could IPP affect cardiac filling?

Answer 3

with pericardial fluid buildup

IPP may increase

Question 4

what determines the hemodynamic effect of a pericardial effusion, and why does this matter?

Answer 4

the IPP, not volume

• if effusion builds slowly, the pericardium may gradually stretch and accumulate a lot of fluid while not causing compression of the cardiac chambers
• if effusion accumulates quickly, pericardium doesn’t have time to stretch and thus the cardiac chambers could be compressed with much less fluid
• *amt of fluid doesn’t determine severity

Question 5

result of cardiac tamponade

Answer 5

abnormal accumulation of fluid in pericardial sac
increased intra pericardial pressure
compresses cardiac chambers
decreased cardiac filling
reduced SV
reduced CO

Question 6

which chamber is the first to be compressed and why

Answer 6

RA

thin, lowest intra cardiac pressure

Question 7

what is the effect of early tamponade?

Answer 7

increase in pressure in RA can reduce the drainage of blood into the cardiac chambers from the IVC and SVC

Question 8

effect of IPP > RA diastolic pressure

Answer 8

late diastolic RA inversion

Question 9

effect of IPP > RV diastolic pressure

Answer 9

early diastolic RV collapse

Question 10

describe the effect of increased inter-ventricular dependence

Answer 10

during inspiration, more blood empties into the right heart
IV septum compresses LV to accommodate widened RV
LV stroke volume decreases
CO decreases
MAP decreases

Question 11

symptoms of cardiac tamponade

Answer 11

with reduced SV and CO, HR is increased to try to maintain CO
increased adrenergic tone : sweating, tachy
low BP: dizziness, fatigue, dyspnea, syncope
salt and water retention: edema, wt gain

Question 12

signs of cardiac tamponade

Answer 12

raised JVP
low BP, fast HR
muffled heart sounds
(Becks triad)

Question 13

what is pulsus paradoxus?

Answer 13

greater than normal decline in systolic arterial pressure during inspiration (greater than 10 mmHg)

Question 14

how can you detect pulsus paradoxus with a stethoscope?

Answer 14

use manual sphygmomanometer
listen for first Kortokoff sound
stop decreasing pressure and have patient breathe slowly
will only hear sounds on expiration until a lower BP is reached

Question 15

how does pericardial tamponade manifest on an ECG?

Answer 15

cardiac muscle further from skin

water/fluid is decreasing transmission of electrical signal

Question 16

CXR findings with cardiac effusions

Answer 16

large cardiac silhouette

Question 17

gold standard imaging technique for effusion

Answer 17

echocardiography

Question 18

what is an echo finding in the case of a large pericardial effusion

Answer 18

heart swings during beats toward chest wall within the fluid sac

Question 19

what is electrical alternans?

Answer 19

electrical manifestation of heart swinging toward anterior chest wall
alternating high and low voltage beats

Question 20

how might pericardial effusion by diagnosed incidentally?

Answer 20

CT or MRI done for another reason and finding one

Question 21

common causes of pericardial effusions

Answer 21

malignancy
infection
trauma
post surgery
inflammation (RA)
uremia
thyroid problems
idiopathic

Question 22

when should you drain a pericardial effusion?

Answer 22

cardiac tamponade
suspicion of infection
large and present for a long time

Question 23

what is the most common type of pericardial effusion fluid?

Answer 23

serous

yellowish

Question 24

what do you do if a pericardial effusion is loculated?

Answer 24

leave a drain in place until drainage stops

may need to open a pericardial window if effusions recur or do not stop draining