Pericardial Tamponade Flashcards
3 poss pericardial compression syndromes?
- cardiac tamponade: accum of pericardial fluid under pressure and may be acute or subacute
- constrictive pericarditis: scarring and cosequent loss of elasticity of pericardial sac
- effusive-constrictive pericarditis: constrictive physiology w/ coexisting pericardial effusion, elevated wedge and Rt sided pressures s/p drainage
What happens to the heart during a cardiac tamponade?
- compression of all cardiac chambers due to increased pericardial pressure
- pericardium has some compliance w/ increased pressure, but once that is exceeded it begins to impair diastolic compliance, reducing cardiac filling
- much of pressure is transmitted to Rt vent/atrium (lower presure systems) which causes bulging of intraventricular septum and decreased Left ventricular compliance and filling
What is a pericardial effusion?
- pericardium usually has 20-50 ml of fluid
- acuity of fluid accum plays large role in complaince of pericardium:
rapid accum (trauma) gives pericardium no time to adjust, therefore small amt of fluid can cause tamponade - slow accum allows compliance to increase allowing larger vol of fluid into sac
- however when periocardial pressures are greater than Rt ventricular prssure tamponade physiology can occur
Causes of pericardial tamponade?
- malignancy
- HIV
- infection: viral, bacterial (TB), fungal
- drugs: hydralazine, procrainamide
- post coronary intervention
- trauma
- CV surgery (MC in US)
- post MI
- CT disease: SLE, RA, dermatomyositis
- radiation
- iatrogenic
- uremia
- idiopathic pericarditis
- complication of surgery: antireflux surgery
Sxs of cardiac tamponade?
- dyspnea, tachycardia, tachypnea
- cold, clammy extremities
- malignancy: wt loss, fatigue, anorexia
- CP: pericarditis, MI
- jt pain: CT
- renal failure: uremia
- meds: drug induced lupus
- TB: will have noc sweats and fever
- radiation - cancer hx
PE findings of cardiac tamponade?
- beck’s triad: increased JVP, hypotension, diminished heart sounds
- hepatomegaly
- evidence of chest wall trauma
- pulsus paradoxsus of more than 12 mm Hg
- kussmaul sign: rise in JVP upon inspiration, (R ventricle can’t tolerate venous flow)
- abolished y descent
Dx of cardiac tamponade?
- EKG: low voltage, sinus tach, PR depression, electrical alternans
- CXR: water bottle shaped heart
- echo: Test of choice - pericardial effusion, early diastolic collapse of right ventricular free wall, late diastolic compression of R atrium, swinging of heart, LV pseudohypertrophy
- Rt heart cath: if pt stable and dx is in doubt: measure R sided pressures, in tamponande: near equalization of R atrial, R ventricular diastolic, pulm artery diastolic and pulmonary cap wedge pressure (PCWP), R atrial pressure tracings show abolished systolic y descent
Tx of cardiac tamponade?
while waiting on CT surgery:
- O2, vol expansion w/ blood, plasma, or NS
- bed rest w/ leg elevation (increase venous return)
- inotropic drugs: dobutamine (choose ones taht don’t increase SVR while increasing CO)
- CT surgery:
pericardiocentesis: can be done fluoroscopically or TTE, pericardial window: involves surgical opening of communication b/t pericardial space and intrapleural space
- recurrent effusion:
pericardectomy
pericardial-peritoneal shunt
pericardiodesis: steroids, tetracycline, or antineoplastic drugs can be instilled into pericadial space sclerosing pericardium
Emergent intervention for cardiac tamponade?
- use 16-18 g needle - insert at 30-45 degree angle to skin, near left xiphocostal angle, aiming towards L shoulder
- when performed emergently - mortality rate: 4%, complication: 17%
Definitive therapy for pericardial effusion/tamponade?
- pericardiocentesis
- commonly performed in cath lab but can be done in ICU or ER
- attach limb leadt to verify location
