Cardiac Tamponade/Pericardial disease

Question 1

Normal intrathoracic changes during spontaneous inspiration

Answer 1

• Decreased intrathoracic pressure
• Increased venous return
• Increased right heart filling
• Less pulmonary venous compression (less “smooshing”)
• Decreased left heart filling
• Slight decrease in BP

Question 2

Normal intrathoracic changes during spontaneous expiration

Answer 2

• Increased intrathoracic pressure
• Decreased venous return
• Decreased right heart filling
• More pulmonary venous compression (more “smooshing”)
• Increased left heart filling
• Slight increase in BP

Question 3

What is pulsus paradoxus? What is its etiology?

Answer 3

> 10mmHg drop in SBP with inspiration

Caused by ventricular interdependence (RV filling –> septal bounce to left –> decreased LV filling –> decreased systemic cardiac output)

Question 4

Echo findings suggested of tamponade

Answer 4

• Diastolic right-sided chamber collapse
• Doppler signs of increased ventricular interdependence
• IVC dilation

Sensitive but not specific:
- RA collapse in early diastole lasting <1/3 cardiac cycle
- IVC >2cm and <50% respiratory variation

Sensitive and specific:
- RA collapse that lasts for more than 1/3 of the cardiac cycle (into systole)

pHTN or RVH may mask findings.

Question 5

What Doppler signs suggest increased ventricular interdependence?

Answer 5

• Decrease in mitral valve inflow E velocity >25% with spontaneous inspiration
• Decrease in tricuspid valve inflow >40% with spontaneous expiration

Question 6

CVP waveform changes in tamponade

Answer 6

• Dominant X descent
• Reduced Y descent “lose your Y, then you die” (increased pericardial pressure decreases passive filling of the RV)

Question 7

What are the different components of a normal CVP tracing?

Answer 7

• y descent: blood emptying from the RA into the RV when the TV opens
• a wave: RA contraction
• c wave: RV contraction
• x descent: RA relaxation
• v wave: RA filling (during systole)

Question 8

PA pressure findings in tamponade

Answer 8

Equalization of all chamber pressures during diastole

Question 9

Anesthetic management and goals in tamponade

Answer 9

• Positive pressure ventilation or increased mean airway pressure can further reduce cardiac output
• Induction of anesthesia can lead to arrest

Goals:
- Maintain sympathetic tone until tamponade relieved
- Avoid cardiac depression, vasodilation, bradycardia

Question 10

Pericardial decompression syndrome

Answer 10

Hemodynamic compromise that occurs within 48 hrs of effusion drainage, due to rapid expansion of right sided chambers (leading to decreased volume to left side)

Question 11

Constrictive pericarditis pathophysiology

Answer 11

• Limited filling in all chambers
• Ventricular filling stops when a critical pressure point reached
• Atrial contraction contributes minimally (E»A)
• Rigid pericardium isolates heart from negative intrathoracic pressure
• Ventricular interdependence

Question 12

CVP waveform in constrictive pericarditis

Answer 12

• Prominent systolic x wave
• Rapid y descent (most filling occurs early diastole)

Question 13

DeBakey types

Answer 13

Type I: ascending to descending (most extensive)
Type II: confined to the ascending
Type III: descending
- IIIa: thoracic aorta only
- IIIb: thoracic + abdominal