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单词 cardiac tamponade
释义

cardiac tamponade


Thesaurus
Noun1.cardiac tamponade - mechanical compression of the heart resulting from large amounts of fluid collecting in the pericardial space and limiting the heart's normal range of motiontamponade, tamponage - blockage or closure (as of a wound or body cavity) by (or as if by) a tampon (especially to stop bleeding)

cardiac tamponade


cardiac tamponade

[′kärd·ē‚ak ¦tam·pə¦nād] (medicine) Cardiac compression caused by an accumulation of fluid within the pericardium.

cardiac tamponade


Cardiac Tamponade

 

Definition

Cardiac tamponade occurs when the heart is squeezed by fluid that collects inside the sac that surrounds it.

Description

The heart is surrounded by a sac called the pericardium. When this sac becomes filled with fluid, the liquid presses on the heart, preventing the lower chambers of the heart from properly filling with blood.Because the lower chambers (the ventricles) cannot fill with the correct amount of blood, less than normal amounts of blood reach the lungs and the rest of the body. This condition is very serious and can be fatal if not treated.

Causes and symptoms

Fluid can collect inside the pericardium and compress the heart when the kidneys do not properly remove waste from the blood, when the pericardium swells from unknown causes, from infection, or when the pericardium is damaged by cancer. Blunt or penetrating injury from trauma to the chest or heart can also result in cardiac tamponade when large amounts of blood fill the pericardium. Tamponade can also occur during heart surgery.When the heart is compressed by the surrounding fluid, three conditions occur: a reduced amount of blood is pumped to the body by the heart, the lower chambers of the ventricles are filled with a less than normal amount of blood, and higher than normal blood pressures occur inside the heart, caused by the pressure of the fluid pushing in on the heart from the outside.When tamponade occurs because of trauma, the sound of the heart beats can become faint, and the blood pressure in the arteries decreases, while the blood pressure in the veins increases.In cases of tamponade caused by more slowly developing diseases, shortness of breath, a feeling of tightness in the chest, increased blood pressure in the large veins in the neck (the jugular veins), weight gain, and fluid retention by the body can occur.

Diagnosis

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. This test uses sound waves to create an image of the heart and its surrounding sac, making it easy to visualize any fluid that has collected inside the sac.

Treatment

If the abnormal fluid buildup in the pericardial sac is caused by cancer or kidney disease, drugs used to treat these conditions can help lessen the amount of fluid collecting inside the sac. Drugs that help maintain normal blood pressure throughout the body can also help this condition; however, these drugs are only a temporary treatment. The fluid within the pericardium must be drained out to reduce the pressure on the heart and restore proper heart pumping.The fluid inside the pericardium is drained by inserting a needle through the chest and into the sac itself. This allows the fluid to flow out of the sac, relieving the abnormal pressure on the heart. This procedure is called pericardiocentesis. In severe cases, a tube (catheter) can be inserted into the sac or a section of the sac can be surgically cut away to allow for more drainage.

Prognosis

This condition is life-threatening. However, drug treatments can be helpful, and surgical treatments can successfully drain the trapped fluid, though it may reaccumulate. Some risk of death exists with surgical drainage of the accumulated fluid.

Resources

Organizations

American Heart Association. 7320 Greenville Ave. Dallas, TX 75231. (214) 373-6300. http://www.americanheart.org.

Key terms

Pericardiocentesis — A procedure used to drain fluid out of the sac surrounding the heart. This is done by inserting a needle through the chest and into the sac.

tamponade

 [tam″po-nād´] 1. surgical use of a tampon.2. pathologic compression of a part.cardiac tamponade compression of the heart due to collection of fluid or blood in the pericardium. It may be either chronic or acute. Chronic cardiac tamponade occurs when fluid slowly enters the pericardial sac, allowing time for the membrane's expansion to accommodate the fluid, which can be as much as 1 liter. This gradual filling may or may not produce changes in cardiac hemodynamics. However, if there is rapid filling of the pericardial sac, as little as 200 ml can precipitate a life-threatening emergency. The ultimate effect of cardiac tamponade is reduced cardiac output and inadequate tissue perfusion.

Causes of acute cardiac tamponade include pericarditis with effusion of serosanguineous fluid into the sac, and either surgical or accidental trauma with leakage of blood into the sac. Occasionally, anticoagulant therapy can lead to extensive bleeding around the heart and cardiac tamponade.
Excessive fluid within the pericardial sac causes pressure against the cardiac structures, interferes with ventricular and atrial filling, and compromises blood supply to the myocardium via the coronary vessels. These conditions occur because of the following events: The compressed atria cannot fill as they normally would and so less blood is available for the ventricles; thus preload (the volume of blood in the ventricles at the end of diastole) is reduced. Ventricular filling is further impaired by compression of the ventricles. As pressure within the ventricles rises because of tamponade, pressure differences between the atria and ventricles are reduced, causing the valves between the two chambers to close before the ventricles have had time to fill completely. Increasing pressure within the heart chambers and in the pericardium impinges on the coronary arteries and veins, reducing blood supply to the myocardium, slowing contractility, and further reducing cardiac output.
Clinical features of cardiac tamponade include increased central venous pressure, falling arterial blood pressure, tachycardia, faint or muffled heart sounds, a narrowing pulse pressure, and an exaggerated inspiratory fall in systolic blood pressure (pulsus paradoxus). Hypoxia of cerebral tissues can produce confusion, restlessness, agitation, panic, and a sense of impending doom. Peripheral hypoxia is signaled by changes in the color, temperature, and excessive sweating.
Diagnosis can be confirmed by echocardiography and other radiologic studies. However, if the situation is acute, these tests cannot be done without endangering the life of the patient; thus diagnosis must be based on clinical findings. Once tamponade is suspected, fluids are administered and a pericardiocentesis is done to remove the compressing fluid.Pericardiocentesis is performed to remove compressing fluid in cardiac tamponade. From Polaski and Tatro, 1996.

car·di·ac tam·po·nade

compression of the heart due to critically increased volume of fluid in the pericardium. Synonym(s): heart tamponade

cardiac tamponade

Interference with the venous return of blood to the heart 2º to accumulation of fluids or blood in pericardium, resulting in ↑ mean right atrial pressure and near-equalization with intrapericardiac pressure, which has a wide range of clinical and hemodynamic effects Etiology 2º to dissecting aneurysm, HTN, post-MI, renal failure, pericarditis, hypothyroidism, autoimmune disease–eg, SLE, chest trauma, CA Diagnosis Echocardiogram Management Pericardiocentesis, ie needle aspiration, pericardial window

car·di·ac tam·pon·ade

(kahr'dē-ak tam'pŏ-nād') Compression of the heart due to critically increased volume of fluid in the pericardium.

cardiac tamponade

Abnormal compression of the heart from outside. This may occur as a result of penetrating injuries or a collection of blood or fluid in the sac surrounding the heart (the PERICARDIUM). Tamponade seriously interferes with heart action and calls for urgent relief.

Cardiac Tamponade

DRG Category:315
Mean LOS:4 days
Description:MEDICAL: Other Circulatory System Diagnoses With CC

Acute cardiac tamponade is a sudden accumulation of fluid in the pericardial sac leading to an increase in the intrapericardial pressure. It is a medical emergency whose outcome depends on the speed of diagnosis and treatment as well as the underlying cause. The pericardial sac surrounds the heart and normally contains only 10 to 20 mL of serous fluid. The sudden accumulation of more fluid (as little as 200 mL of fluid or blood) compresses the heart and coronary arteries, compromising diastolic filling and systolic emptying and diminishing oxygen supply. The end result is decreased oxygen delivery and poor tissue perfusion to all organs.

The incidence of cardiac tamponade in the United States is 2 cases per 10,000 individuals, and approximately 2% of penetrating injuries lead to cardiac tamponade. It is a potentially life-threatening condition, needing emergency assessment and immediate interventions. Some patients develop a more slowly accumulating tamponade that collects over weeks and months. If the fibrous pericardium gradually has time to stretch, the pericardial space can accommodate as much as 1 to 2 L of fluid before the patient becomes acutely symptomatic. Three phases of hemodynamic changes occur with acute cardiac tamponade (Table 1). Complications include decreased ventricular filling, decreased cardiac output, cardiogenic shock, and death.

Phases of Cardiac Tamponade
Table 1. Phases of Cardiac Tamponade
PHASEDESCRIPTION
Phase 1Accumulation of pericardial fluid leads to increased ventricular stiffness, which requires a higher filling pressure; left and right ventricular filling pressures are higher than the intrapericardial pressure during this phase
Phase 2As fluid accumulates, pericardial pressure increases above the ventricular filling pressure; cardiac output thereby is reduced
Phase 3Decrease in cardiac output continues due to equilibration of pericardial and left ventricular filling pressures

Causes

Cardiac tamponade may have any of a variety of etiologies. It can be caused by both blunt and penetrating traumatic injuries and also iatrogenic injuries, such as those associated with removal of epicardial pacing wires and complications after cardiac catheterization and insertion of central venous or pulmonary artery catheters.

Rupture of the ventricle after an acute myocardial infarction or bleeding after cardiac surgery can also lead to tamponade. Other causes include treatment with anticoagulants, viral infections such as HIV, and disorders that cause pericardial irritation such as pericarditis, neoplasms tuberculosis, or myxedema, as well as collagen diseases such as rheumatoid arthritis or systemic lupus erythematosus.

Genetic considerations

Cardiac tamponade is typically not heritable, but it is more common among patients with Marfan’s syndrome or others with heritable connective tissue disease.

Gender, ethnic/racial, and life span considerations

Although a patient of any age can develop a cardiac tamponade, the very young and the elderly have fewer reserves available to cope with such a severe condition. Because trauma is the leading cause of death for individuals in the first four decades of life, traumatic tamponade is more common in that age group, whereas the older adult is more likely to have an iatrogenic tamponade. Males have higher rates of unintentional injury than do females; in children, cardiac tamponade is more common in boys than in girls with a male-to-female ratio of 7:3. Cardiac tamponade related to HIV infection is more common in young adults, whereas cardiac tamponade due to malignancy or renal failure is more often seen in elderly patients. Ethnicity and race have no known effect on the risk of cardiac tamponade, but more males than females develop pericarditis.

Global health considerations

Traumatic injury resulting in pericardial bleeding or tuberculosis resulting in pericardial effusions are the most common causes of cardiac tamponade in developing nations. Pericardial effusions most commonly result from malignancies in developed nations, but motor vehicle crashes and myocardial rupture also contribute to the prevalence.

Assessment

History

The patient’s history may include surgery, trauma, cardiac biopsy, viral infection, insertion of a transvenous pacing wire or catheter, or myocardial infarction. Elicit a medication history to determine if the patient is taking anticoagulants or any medication that could cause tamponade as a drug reaction (procainamide, hydralazine, minoxidil, isoniazid, penicillin, methysergide, or daunorubicin). Ask if the patient has renal failure, which can lead to pericarditis and bleeding. Cardiac tamponade may be acute or accumulate over time, as in the case of myxedema, collagen diseases, and neoplasm. The patient may have a history of dyspnea and chest pain that ranges from mild to severe and increases on inspiration. There may be no symptoms at all before severe hemodynamic compromise.

Physical examination

The primary symptoms are related to shock: dyspnea, tachycardia, tachypnea, pallor, and cold extremities. The patient who has acute, rapid bleeding with cardiac tamponade appears critically ill and in shock. Assess airway, breathing, and circulation (ABCs), and intervene simultaneously. The patient is acutely hypovolemic (because of blood loss into the pericardial sac) and in cardiogenic shock and should be assessed and treated for those conditions as an emergency situation.

If the patient is more stable, when you auscultate the heart, you may hear a pericardial friction rub as a result of the two inflamed layers of the pericardium rubbing against each other. The heart sounds may be muffled because of the accumulation of fluid around the heart. If a central venous or pulmonary artery catheter is present, the right atrial mean pressure (RAP) rises to greater than 12 mm Hg, and the pulmonary capillary wedge pressure equalizes with the RAP. Systolic blood pressure decreases as the pressure on the ventricles reduces diastolic filling and cardiac output. Pulsus paradoxus (> 10 mm Hg fall in systolic blood pressure during inspiration) is an important finding in cardiac tamponade and is probably related to blood pooling in the pulmonary veins during inspiration. Other signs that may be present are related to the decreased cardiac output and poor tissue perfusion. Confusion and agitation, cyanosis, tachycardia, and decreased urine output may all occur as cardiac output is compromised and tissue perfusion becomes impaired.

Assessment of cardiovascular function should be performed hourly; check mental status, skin color, temperature and moisture, capillary refill, heart sounds, heart rate, arterial blood pressure, and jugular venous distention. Maintain the patient on continuous cardiac monitoring, and monitor for ST-wave and T-wave changes.

Psychosocial

Acute cardiac tamponade can be sudden, unexpected, and life-threatening, causing the patient to experience fear and anxiety. Assess the patient’s degree of fear and anxiety, as well as her or his ability to cope with a sudden illness and threat to self. The patient’s family or significant other(s) should be included in the assessment and plan of care. Half of all patients with traumatic injuries have either alcohol or other drugs present in their systems at the time of injury. Ask about the patient’s drinking patterns and any substance use and abuse. Assess the risk for withdrawal from alcohol or other drugs during the hospitalization.

Diagnostic highlights

TestNormal ResultAbnormality With ConditionExplanation
EchocardiogramNormal size, shape, position, thickness, and movement of structuresEcho-free zone anterior to right ventricular wall and posterior to the left ventricular wall; there may also be a decrease in right ventricular chamber size and a right-to-left septal shift during inspirationRecords echoes created by deflection of short pulses of ultrasonic beam off cardiac structures; may also be done as a transesophageal procedure with transmitter inserted into esophagus (transesophageal echocardiogram)

Other Tests: Prolonged coagulation studies and/or a decreased hemoglobin and hematocrit if the patient has lost sufficient blood into the pericardium; electrocardiogram and chest x-ray; computed tomography; arterial blood gases; creatine kinase and isoenzymes; HIV testing

Primary nursing diagnosis

Diagnosis

Decreased cardiac output related to decreased preload and contractility.

Outcomes

Circulation status; Cardiac pump effectiveness; Tissue perfusion: Abdominal organs and peripheral; Vital signs status; Fluid balance

Interventions

Cardiac care: Acute, Fluid/electrolyte management, Fluid monitoring; Shock management: Volume, Medication administration, Circulatory care

Planning and implementation

Collaborative

The highest priority is to make sure the patient has adequate ABCs. If the patient suffers hypoxia as a result of decreased cardiac output and poor tissue perfusion, oxygen, intubation, and mechanical ventilation may be required. If the symptoms are progressing rapidly, the physician may elect to perform a pericardiocentesis to normalize pericardial pressure, allowing the heart and coronary arteries to fill normally so that cardiac output and tissue perfusion are restored. Assist by elevating the head of the bed to a 60-degree angle to allow gravity to pull the fluid to the apex of the heart. Emergency equipment should be nearby because ventricular tachycardia, ventricular fibrillation, or laceration of a coronary artery or myocardium can cause shock and death. Pericardiocentesis usually causes a dramatic improvement in hemodynamic status. However, if the patient has had rapid bleeding into the pericardial space, clots may have formed that block the needle aspiration. A false-negative pericardiocentesis is therefore possible and needs to be considered if symptoms continue.

The patient must be taken to surgery after this procedure to explore the pericardium and stop further bleeding. If the patient has developed sudden bradycardia (heart rate < 50 beats per minute), severe hypotension (systolic blood pressure < 70 mm Hg), or asystole, an emergency thoracotomy may be performed at the bedside to evacuate the pericardial sac, control the hemorrhage, and perform internal cardiac massage if needed. The patient may also require fluid resuscitation agents to enhance cardiac output.

Pharmacologic highlights

Medication or Drug ClassDosageDescriptionRationale
Sympathomimetics such as dopamine hydrochlorideVaries by drugStimulates adrenergic receptors to increase myocardial contractility and peripheral resistanceSupports blood pressure and cardiac output in emergencies until bleeding is brought under control; only used if fluid resuscitation is initiated

Independent

The highest nursing priority is to maintain the patient’s ABCs. Emergency equipment should be readily available in case the patient requires intubation and mechanical ventilation. Be prepared to administer fluids, including blood products, colloids or crystalloids, and pressor agents, through a large-bore catheter. Pressure and rapid-volume warmer infusors should be used for patients who require massive fluid resuscitation. A number of nursing strategies increase the rate of fluid replacement. Fluid resuscitation is most efficient through a short, large-bore peripheral intravenous (IV) catheter in a large peripheral vein. The IV should have a short length of tubing from the bag or bottle to the IV site. If pressure is applied to the bag, fluid resuscitation occurs more rapidly.

Emotional support of the patient and family is also a key nursing intervention. If the patient is awake as you implement strategies to manage the ABCs, provide a running explanation of the procedures. If blood component therapy is essential, answer the patient’s and family’s questions about the risks of hepatitis and transmission of HIV.

Evidence-Based Practice and Health Policy

Mahon, L., Bena, J.F., Morrison, S.M., & Albert, N.M. (2012). Cardiac tamponade after removal of temporary pacer wires. American Journal of Critical Care, 21(6), 432–440.

  • Intensive monitoring for the first 3 hours following removal of temporary pacer wires, which are routinely placed following cardiac surgery, is recommended by the American Association of Critical-Care Nurses to identify complications, such as cardiac tamponade.
  • A cross-sectional review of 23,717 medical records of patients who underwent cardiac surgery at the Cleveland Clinic in northeast Ohio revealed that reoperation for cardiac tamponade occurred in less than 1% of the sample population (9.7 cases per 10,000). In the total sample, 73% had hypertension, 47% had peripheral artery disease, 44% had a history of myocardial infarction, 10% had atrial fibrillation or flutter, and 10% had a ventricular dysrhythmia.
  • Among patients who underwent reoperation for cardiac tamponade, 80% were smokers compared to 60% of those who did not have a reoperation (p = 0.06), and 48% had a history of heart failure compared to 29% of those who did not have a reoperation (p = 0.08).
  • Symptoms of cardiac tamponade following removal of the temporary pacer wires in this sample included dyspnea within 4 hours of removal, hypotension, tachycardia, bleeding into the chest tube or pleural drain, and cardiac arrest. Blood pressure changes were the single most common sign, occurring in 52% of patients who required reoperation for cardiac tamponade.

Documentation guidelines

  • Physical findings of cardiovascular and neurological systems
  • Adequacy of ABCs, mental status, skin color, vital signs, moisture of mucous membranes, capillary refill, heart sounds, presence of pulsus paradoxus or jugular venous distention, hemodynamic parameters, intake and output
  • Response to interventions
  • Fluid resuscitation, inotropic agents, pericardiocentesis, surgery
  • Presence of complications
  • Asystole, ventricular tachycardia, ventricular fibrillation; recurrence of tamponade; infection; ongoing hemorrhage

Discharge and home healthcare guidelines

medications.
Be sure the patient understands all medications, including dosage, route, side effects, and any routine laboratory testing. The patient needs to understand to avoid over-the-counter medications, including aspirin and ibuprofen.

complications.
The patient needs to understand the possibility of recurrence and the symptoms to report to the physician. The patient and significant other(s) also need to understand that symptoms of inadequate tissue perfusion (change in mental status; cool, clammy, cyanotic skin; dyspnea; chest pain) warrant activation of the emergency medical system.

cardiac tamponade


  • noun

Words related to cardiac tamponade

noun mechanical compression of the heart resulting from large amounts of fluid collecting in the pericardial space and limiting the heart's normal range of motion

Related Words

  • tamponade
  • tamponage
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更新时间:2024/12/23 23:51:03