Cardiac tamponade is a condition caused by rapid buildup of fluid (usually blood, but some conditions cause other fluids to collect) in the pericardial sac (see question below for definition of pericardium).
Small amounts of fluid or fluid that accumulates over a long period of time does not cause problems, but when the fluid volume becomes too high or it accumulates rapidly, the pressure within the pericardium rises and may eventually lead to compression of the cardiac chambers, restricting filling and emptying. This is most prominent in the right sided chambers, specifically the right atrium and ventricle. Restriction of filling results in a decrease in cardiac output and eventually hypotension, shock, and (if uncorrected) death. This is a not uncommon cause of PEA (pulseless electrical activity) in traumatically injured patients.
Signs and symptoms of cardiac tamponade include the classic signs of hypotension/shock, jugular venous distention and muffled heart sounds. Together, these signs bear the eponym "Beck's triad." Not all patients with cardiac tamponade will have all of these signs, however. Clinical suspicion in the appropriate setting still plays a major role in diagnosis. Other signs include those caused by these three core signs - altered mental status, weak or absent peripheral pulses, cyanosis, respiratory distress or failure, diaphoresis, tachycardia as the heart tries to compensate for a decreased output and hypotension, decreased urine output, and others.
Diagnosis of cardiac tamponade is done either on appropriate clinical suspicion in appropriate patients and physical exam or by ultrasound at the bedside. Rapid bedside ultrasound will reveal a large pericardial effusion with compression of the R heart structures, particularly in diastole. This is diagnostic of cardiac tamponade.
Treatment includes pericardiocentesis at bedside, either blindly or ultrasound guided or emergent pericardial window in the OR. In traumatic cases, particularly penetrating trauma, the cause is an atrial or ventricular injury or proximal aortic injury and these treatments will cause only temporary improvement with worsening again upon reaccumulation of blood. In this case, the treatment is thoracotomy and primary repair of the cardiac injury. Emergency thoractomy may be performed in the emergency department as a temporizing measure to give the patient time to make it to the OR when vital signs are lost, but overall mortality is high.
See the related questions for more information.
Cardiac tamponade
Cardiac tamponade is a serious medical emergency and must be treated immediately.
a stab wound to the heart can result in cardiac tamponade
no
Cardiac tamponade has an incidence of two in 10,000 the general U.S. population. Approximately 2% of cases are attributed to injuries that penetrate the chest.
cardiogenic
When cardiac tamponade is suspected, accurate diagnosis can be life-saving. The most accurate way to identify this condition is by using a test called an echocardiogram.
The condition keeps the rest of the body from getting the necessary supply of oxygen and can cause dangerously low blood pressure.
Cardiac tamponade
Pericardial aspiration is a procedure where a needle is inserted into the pericardial sac surrounding the heart to remove excess fluid, relieving pressure on the heart and improving cardiac function. This procedure is typically done to diagnose and treat conditions like pericarditis or cardiac tamponade.
Cardiac tamponade and pericarditis are two primary complications that require intervention with pericardiocentesis.
Pericarditis is inflammation of the sac around the heart.