Cardiac tamponade

Definition

Accumulation of fluid in the pericardium

Epidemiology

Pathophysiology

The reason this is such a big deal is because if enough fluid gets into the pericardium (bit around the heart), it begins to affect stroke volume as it prevents the ventricles from filling properly. Reduced stroke volume leads to reduced cardiac output and, if left, cardiogenic shock and death.

Causes: trauma, lung/breast cancer, pericarditis, MI, rarely TB.

Clinical Features

The key ones are: hypotension, raised JVP on inspiration and muffled heart sounds.

Others include: shortness of breath, pulsus paradoxus (pulse fades on inspiration).

Investigations

• Echocardiography
• CXR - convex left heart border, globular heart, right cardiophrenic angle <90^o.
• ECG - amplitude or axis of QRS complexes change between beats (electrical alternans).

Management

• ABC
• Give high-flow 100% O₂
• Establish iv
• Call for help (from a senior, not just a porter or another patient)
• Pericardiocentesis.