Pericardial effusion and tamponade

Pathophysiology

-see pericarditis

-hemodynamic compromise from inc pericardial fluid

    -incr pericardial pressures

    -decr diastolic filling, venous return, collapse of RA

    -inhalation sequesters fluid in pulm vasc, not LV

Signs & Symptoms

-Rapidity of fluid accumulation determines clinical effects

-Rapid accumulation: as little as 150cc may decr cardiac output

-Slow accumulation: as much as 2L may have little effect

-Pts may c/o CP, dyspnea, fatigue, anorexia, wt loss, MS changes, shock

-Overall: looks a lot like CHF with JVD, SOB, hepatomegaly, etc...

-Narrow pulse pressure

-Friction rub

-Beck's Triad: hypotension, muffled heart sounds, JVD

    -present in only 30% of pts

    -90% will have at least one of the three findings

-Pulsus paradoxus

    - >10mmHg change in sys BP on inspiration

         -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

    -can see in many right heart dz states as well

    -may NOT see in acute trauma

-Ewart's sign (compressive atelectasis causes pulmonary auscultatory changes)

Work-Up

-Pulsus paradoxus (old school)

-EKG -nl or diffuse low QRS

    -electrical alternans (beat to beat QRS amp vary)

-CXR: CM, obliteration of costophrenic angles

-TTE -modality of choice: effusion, diffuse hypokinesis, RA and RV collapse

-labs: CBC, chem 10, coags, enzymes

-consider: HIV, ANA, ESR, RF, PPD

-pericardial fluid for viral/bact Cx, cell count, cytology

Causes

As in pericarditis

- idiopathic

- infectious, including AIDS related, TB

- malignancy: heme, lung, breast

- uremia

- post radiation

- connective tissue dz

- drugs: procainamide, hydralaine, methyldopa, anticoagulants

- cardiac injury (can see up to weeks later): post MI, trauma, aortic dissection

DDx

Tension PTX

PE

SVC syndrome

large pleural effusion

Tension pneumocardium

Constrictive pericarditis

Cardiogenic shock

Treatment

EMERGENCY

-ABCs, IV, O2, monitor

-IV fluids to incr RV vol

-Pressors (temporizing)

-AVOID preload reducing meds eg Nitrates, diuretics

-Procedures: see Pericardiocentesis

-Pericardial window (OR)

Disposition

-likely ICU

-Cards, CT surg consults

Source

Cards: Pericarditis

Source

Adapted from Donaldson