Pericardial effusion and tamponade

Pathophysiology

1. see pericarditis
2. hemodynamic compromise from inc pericardial fluid
   1. incr pericardial pressures
   2. decr diastolic filling, venous return, collapse of RA
   3. inhalation sequesters fluid in pulm vasc, not LV

Signs & Symptoms

1. Rapidity of fluid accumulation determines clinical effects
2. Rapid accumulation: as little as 150cc may decr cardiac output
3. Slow accumulation: as much as 2L may have little effect
4. Pts may c/o CP, dyspnea, fatigue, anorexia, wt loss, MS changes, shock
5. Overall: looks a lot like CHF with JVD, SOB, hepatomegaly, etc...
6. Narrow pulse pressure
7. Friction rub
8. Beck's Triad
   1. hypotension, muffled heart sounds, JVD
   2. present in only 30% of pts
   3. 90% will have at least one of the three findings
9. Pulsus paradoxus
   1. >10mmHg change in sys BP on inspiration
   2. decreased intrathoracic P on inspiration causes increased return to R heart --> R septum bows into L given constriction by surrounding pericardial effusion --> decreased LVEDV and concomitant decreased CO
   3. can see in many right heart dz states as well
   4. may NOT see in acute trauma
10. Ewart's sign (compressive atelectasis causes pulmonary auscultatory changes)

Work-Up

1. Pulsus paradoxus (old school)
2. EKG
   1. nl or diffuse low QRS
   2. electrical alternans (beat to beat QRS amp vary)
3. CXR: CM, obliteration of costophrenic angles
4. TTE -modality of choice: effusion, diffuse hypokinesis, RA and RV collapse
5. labs: CBC, chem 10, coags, enzymes
6. consider: HIV, ANA, ESR, RF, PPD
7. pericardial fluid for viral/bact Cx, cell count, cytology

Causes

As in pericarditis

1. idiopathic
2. infectious, including AIDS related, TB
3. malignancy: heme, lung, breast
4. uremia
5. post radiation
6. connective tissue dz
7. drugs: procainamide, hydralaine, methyldopa, anticoagulants
8. cardiac injury (can see up to weeks later): post MI, trauma, aortic dissection

DDx

1. Tension PTX
2. PE
3. SVC syndrome
4. large pleural effusion
5. Tension pneumocardium
6. Constrictive pericarditis
7. Cardiogenic shock

Treatment

EMERGENCY

1. ABCs, IV, O2, monitor
2. IV fluids to incr RV vol
3. Pressors (temporizing)
4. AVOID preload reducing meds eg Nitrates, diuretics
5. Procedures: see Pericardiocentesis
6. Pericardial window (OR)

Disposition

1. likely ICU
2. Cards, CT surg consults

Source

Cards: Pericarditis

Source

Adapted from Donaldson