Decreased Cardiac Output: Nursing Diagnosis and Comprehensive Care Plan

Cardiac output (CO) is a vital hemodynamic parameter that reflects the heart’s efficiency in delivering oxygen and nutrients to the body’s tissues. Defined as the volume of blood pumped by the heart per minute, cardiac output is the product of heart rate (HR) and stroke volume (SV). When cardiac output is compromised, it signifies that the heart is not pumping enough blood to meet the metabolic demands of the body, leading to a cascade of physiological imbalances. This condition, known as decreased cardiac output, is a significant concern in various clinical settings and requires prompt recognition and effective nursing interventions.

In this comprehensive guide, we will delve into the nursing diagnosis of decreased cardiac output, exploring its causes, signs and symptoms, and evidence-based nursing care plan. This resource aims to equip nurses and healthcare professionals with the knowledge and strategies to effectively manage patients experiencing this critical cardiovascular issue.

Causes of Decreased Cardiac Output

Decreased cardiac output is not a disease itself but rather a physiological consequence of various underlying conditions that impair the heart’s ability to function effectively as a pump. These causes can be broadly categorized into factors affecting heart rate, stroke volume, preload, afterload, and contractility. Understanding these factors is crucial for identifying the root cause of decreased cardiac output and tailoring appropriate interventions.

Here are some key causes related to decreased cardiac output:

• Conditions Affecting Heart Rate:

  • Bradycardia: An abnormally slow heart rate reduces the number of cardiac cycles per minute, directly lowering cardiac output.
  • Tachycardia (especially rapid rates): While initially tachycardia can be a compensatory mechanism, excessively rapid heart rates can reduce ventricular filling time, ultimately decreasing stroke volume and cardiac output.
  • Arrhythmias: Irregular heart rhythms, such as atrial fibrillation or ventricular arrhythmias, disrupt the coordinated pumping action of the heart, leading to inefficient blood ejection and reduced cardiac output.

• Conditions Affecting Stroke Volume:

  • Hypovolemia: Reduced blood volume (preload) due to dehydration, hemorrhage, or excessive fluid loss decreases ventricular filling and consequently stroke volume.
  • Cardiomyopathy: Diseases of the heart muscle impair contractility, reducing the force of ventricular ejection and stroke volume.
  • Myocardial Ischemia and Infarction: Reduced blood flow to the heart muscle (ischemia) or heart attack (infarction) damages cardiac tissue, weakening contractility and stroke volume.
  • Valvular Heart Disease: Valve stenosis or regurgitation disrupts normal blood flow through the heart, affecting ventricular filling and ejection, and ultimately reducing stroke volume.
  • Congestive Heart Failure: A chronic condition where the heart is unable to pump sufficient blood to meet the body’s needs. Heart failure encompasses various mechanisms that reduce stroke volume and cardiac output over time.

• Conditions Affecting Preload:

  • Hypovolemia (as mentioned above): Directly reduces preload.
  • Venodilation: Excessive dilation of veins reduces venous return to the heart, decreasing preload.

• Conditions Affecting Afterload:

  • Hypertension: Increased systemic vascular resistance (afterload) makes it harder for the heart to eject blood, reducing stroke volume and cardiac output over time.
  • Pulmonary Hypertension: Increased resistance in the pulmonary circulation increases afterload for the right ventricle, potentially affecting overall cardiac output.
  • Aortic Stenosis: Narrowing of the aortic valve increases afterload, hindering ventricular ejection.

• Conditions Affecting Contractility:

  • Myocardial Ischemia/Infarction (as mentioned above): Damages heart muscle and reduces contractility.
  • Electrolyte Imbalances: Abnormal levels of electrolytes like calcium, potassium, and magnesium can impair myocardial contractility.
  • Acidosis: Acidic conditions in the body can depress myocardial function.
  • Certain Medications: Some medications can have negative inotropic effects, reducing contractility.
  • Hypoxia: Lack of oxygen to the heart muscle reduces its ability to contract effectively.
  • Shock: Various types of shock (cardiogenic, hypovolemic, septic, etc.) can lead to decreased cardiac output through different mechanisms affecting contractility, preload, or afterload.
  • Cardiac Structural Abnormalities: Congenital heart defects or acquired structural problems can impair heart function and cardiac output.
  • Pericardial Effusion and Cardiac Tamponade: Fluid accumulation in the pericardial sac (pericardial effusion) or compression of the heart due to fluid (cardiac tamponade) restricts ventricular filling and reduces cardiac output.

It is important to note that this is not an exhaustive list, and decreased cardiac output can be multifactorial. A thorough assessment is crucial to identify the specific contributing factors in each patient.

Signs and Symptoms of Decreased Cardiac Output

The clinical manifestations of decreased cardiac output are diverse and depend on the severity and chronicity of the condition, as well as the individual’s compensatory mechanisms. Signs and symptoms arise from the body’s attempt to compensate for inadequate tissue perfusion and can affect various organ systems.

Here are common signs and symptoms categorized as physiological and psychological manifestations:

Physiological Signs and Symptoms:

• Cardiovascular:

  • Hypotension: Low blood pressure due to reduced blood volume and pumping efficiency.
  • Tachycardia or Bradycardia: Heart rate abnormalities as the body attempts to compensate for reduced cardiac output.
  • Cardiac Arrhythmias: Irregular heart rhythms can be both a cause and a consequence of decreased cardiac output.
  • Chest Pain (Angina): Reduced oxygen supply to the heart muscle can cause ischemic chest pain.
  • Weak or Diminished Peripheral Pulses: Poor tissue perfusion leads to weakened peripheral pulses, especially in extremities.
  • Cool, Clammy Skin: Vasoconstriction in peripheral tissues to shunt blood to vital organs results in cool and clammy skin.
  • Edema: Fluid retention due to reduced renal perfusion and activation of the renin-angiotensin-aldosterone system (RAAS) can lead to peripheral edema, pulmonary edema, or generalized edema.
  • Jugular Vein Distention (JVD): Increased venous pressure due to heart failure can cause distention of jugular veins.

• Respiratory:

  • Dyspnea (Shortness of Breath): Pulmonary congestion and poor oxygen delivery to tissues trigger shortness of breath, especially on exertion or lying down (orthopnea).
  • Tachypnea (Increased Respiratory Rate): Compensatory mechanism to increase oxygen intake.
  • Hypercapnia (Increased CO2 in blood): In severe cases, poor gas exchange can lead to carbon dioxide retention.
  • Adventitious Breath Sounds (Crackles/Rales): Pulmonary edema can cause abnormal lung sounds like crackles.

• Neurological:

  • Dizziness, Lightheadedness, Syncope: Reduced cerebral perfusion can cause dizziness, lightheadedness, or fainting.
  • Altered Mental Status, Confusion: Severe reduction in cerebral blood flow and oxygenation can lead to confusion, restlessness, and altered level of consciousness.
  • Fatigue, Weakness: Generalized weakness and fatigue due to inadequate oxygen and nutrient delivery to muscles.

• Renal:

  • Decreased Urine Output (Oliguria): Reduced renal blood flow leads to decreased urine production.

Psychological Signs and Symptoms:

• Anxiety: Physiological stress and awareness of bodily changes can induce anxiety.
• Restlessness: Hypoxia and discomfort can cause restlessness.
• Confusion: As mentioned above, altered mental status can manifest as confusion.

It is crucial to recognize that these signs and symptoms can be subtle initially and may worsen as cardiac output further declines. A comprehensive assessment is necessary to identify and interpret these manifestations accurately.

Alt Text: A nurse uses a stethoscope to auscultate a patient’s chest, assessing heart and lung sounds as part of a cardiac output evaluation.

Expected Outcomes for Decreased Cardiac Output

The primary goals of nursing care for patients with decreased cardiac output are to improve cardiac function, optimize tissue perfusion, and alleviate symptoms. Expected outcomes are patient-centered and measurable, guiding the nursing care plan.

Common expected outcomes include:

• Adequate Cardiac Output: Patient will demonstrate adequate cardiac output as evidenced by:

  • Blood pressure and heart rate within acceptable limits for the patient.
  • Regular heart rhythm or controlled arrhythmia.
  • Strong peripheral pulses.
  • Warm and dry skin.
  • Appropriate urine output for age and condition.
  • Absence of chest pain, dyspnea, or edema.
  • Stable hemodynamic parameters (if monitored invasively).

• Improved Activity Tolerance: Patient will return to baseline activity level or demonstrate improved tolerance for activity without significant symptoms of decreased cardiac output (e.g., excessive fatigue, dyspnea, chest pain).

• Optimal Respiratory Function: Patient will exhibit adequate breathing as evidenced by:

  • Oxygen saturation within normal limits (as prescribed).
  • Absence of adventitious breath sounds.
  • Respiratory rate and pattern within normal limits.
  • Absence of dyspnea at rest or with activity within patient’s limitations.

• Effective Self-Care Management: Patient will verbalize understanding of self-care activities to promote cardiac health and prevent further deterioration, including medication management, dietary modifications, activity guidelines, and recognition of worsening symptoms.

These expected outcomes are individualized based on the patient’s condition, comorbidities, and overall goals of care. Regular evaluation of progress toward these outcomes is essential to adjust the care plan as needed.

Nursing Assessment for Decreased Cardiac Output

A thorough nursing assessment is the cornerstone of effective care for patients with decreased cardiac output. It involves systematic data collection to identify the patient’s current cardiovascular status, contributing factors, and response to interventions. The assessment includes both subjective and objective data.

Key Nursing Assessments:

1. Monitor Heart Rate and Blood Pressure:

   • Assess apical and peripheral pulses for rate, rhythm, and quality.
   • Measure blood pressure in both arms, noting any orthostatic changes.
   • Rationale: Low cardiac output can trigger the sympathetic nervous system, initially increasing heart rate and blood pressure as compensatory mechanisms. However, prolonged decreased cardiac output can lead to hypotension as the heart fails to maintain adequate pressure.

2. Monitor Respiratory Rate, Pattern, Breath Sounds, and Oxygen Saturation:

   • Observe respiratory rate, depth, and effort.
   • Auscultate breath sounds for adventitious sounds (crackles, wheezes).
   • Continuously monitor oxygen saturation using pulse oximetry.
   • Rationale: Decreased cardiac output often leads to pulmonary congestion and impaired gas exchange, resulting in dyspnea, tachypnea, and decreased oxygen saturation. Adventitious breath sounds may indicate fluid overload in the lungs.

3. Monitor Heart Rhythm via ECG:

   • Continuously monitor ECG rhythm, especially in acute settings or for patients with known arrhythmias.
   • Identify any arrhythmias (e.g., atrial fibrillation, ventricular tachycardia).
   • Rationale: Arrhythmias can be both a cause and a consequence of decreased cardiac output. Monitoring rhythm is crucial for early detection and management of potentially life-threatening arrhythmias.

4. Assess Heart Sounds:

   • Auscultate heart sounds for S1, S2, and any extra heart sounds (S3, S4), murmurs, or rubs.
   • Note the intensity of heart sounds.
   • Rationale: Normal heart sounds (S1, S2) may be diminished in poor heart function. S3 and S4 sounds can be indicative of heart failure. Murmurs may suggest valvular disease.

5. Assess Peripheral Pulses:

   • Palpate peripheral pulses (radial, femoral, dorsalis pedis, posterior tibial) for presence, strength, and equality bilaterally.
   • Rationale: Decreased cardiac output results in reduced peripheral perfusion, leading to weak or diminished pulses.

6. Assess Skin Color and Temperature:

   • Observe skin color (pallor, cyanosis) and temperature (cool, clammy).
   • Assess capillary refill time.
   • Rationale: Poor tissue perfusion due to decreased cardiac output causes vasoconstriction, resulting in pale, cool, and clammy skin. Delayed capillary refill also indicates poor perfusion.

7. Assess Mental Status:

   • Evaluate level of consciousness, orientation, and cognitive function.
   • Assess for restlessness, confusion, or lethargy.
   • Rationale: Reduced cerebral blood flow and oxygenation can lead to altered mental status, ranging from mild confusion to coma.

8. Review Laboratory Values and Diagnostic Studies:

   • Monitor electrolytes (sodium, potassium, calcium, magnesium), BUN, creatinine, cardiac enzymes (troponin), and complete blood count.
   • Review results of ECG, chest X-ray, echocardiogram, and other cardiac imaging studies.
   • Rationale: Lab values and diagnostic tests help identify underlying causes of decreased cardiac output and assess the severity of organ dysfunction.

9. Monitor Weight and Fluid Balance:

   • Weigh patient daily at the same time, using the same scale.
   • Monitor intake and output (oral, intravenous fluids, urine, drains, etc.).
   • Assess for signs of fluid retention (edema, JVD, weight gain).
   • Rationale: Decreased cardiac output can lead to fluid retention and edema. Monitoring weight and I&O helps assess fluid balance and response to treatment.

10. Assess Activity Level and Tolerance:

    • Inquire about patient’s usual activity level and any changes.
    • Assess for fatigue, dyspnea, or chest pain with activity.
    • Rationale: Reduced cardiac output limits the body’s ability to meet metabolic demands during activity, leading to fatigue and decreased activity tolerance.

These assessments provide a comprehensive picture of the patient’s cardiovascular status and guide the development of individualized nursing interventions.

Alt Text: A nurse measures a patient’s blood pressure using an automated cuff, a routine assessment for monitoring cardiac output.

Nursing Interventions for Decreased Cardiac Output

Nursing interventions for decreased cardiac output are aimed at improving cardiac function, reducing cardiac workload, optimizing tissue perfusion, and managing symptoms. These interventions are evidence-based and tailored to the patient’s specific needs and underlying causes.

Key Nursing Interventions:

1. Administer Supplemental Oxygen as Prescribed:

   • Apply supplemental oxygen via nasal cannula, face mask, or mechanical ventilation as ordered to maintain adequate oxygen saturation.
   • Rationale: Supplemental oxygen increases the oxygen available to tissues, improving oxygen delivery and reducing hypoxia.

2. Administer Prescribed Medications:

   • Administer cardiac medications as ordered, such as:
     • Inotropes (e.g., digoxin, dobutamine): To increase myocardial contractility.
     • Diuretics (e.g., furosemide, hydrochlorothiazide): To reduce fluid overload and preload.
     • Vasodilators (e.g., nitroglycerin, ACE inhibitors, ARBs): To reduce afterload and improve blood flow.
     • Beta-blockers: To control heart rate and reduce myocardial workload (in some cases).
     • Antiarrhythmics: To manage arrhythmias and maintain a regular heart rhythm.
   • Monitor patient response to medications and for any adverse effects.
   • Rationale: Medications play a crucial role in improving cardiac function, managing symptoms, and addressing underlying causes of decreased cardiac output.

3. Elevate Head of Bed:

   • Position patient in a semi-Fowler’s or high-Fowler’s position unless contraindicated.
   • Rationale: Elevating the head of the bed promotes lung expansion, improves ventilation, and reduces venous return (preload), easing the workload on the heart.

4. Implement Fluid and/or Sodium Restrictions as Prescribed:

   • Monitor fluid intake and output closely.
   • Restrict fluid intake and/or sodium intake as ordered by the physician.
   • Rationale: Fluid and sodium restrictions help manage fluid overload, reduce preload, and prevent further edema formation, especially in heart failure.

5. Promote Rest and Activity Balance:

   • Initially, encourage bed rest during the acute phase to reduce cardiac workload.
   • As patient’s condition stabilizes, gradually increase activity levels as tolerated, monitoring for signs of fatigue or decompensation.
   • Rationale: Rest reduces myocardial oxygen demand. Gradual activity progression helps improve strength and endurance without overstressing the heart.

6. Educate Patient and Family on Self-Care:

   • Provide comprehensive education on the patient’s condition, medications, dietary modifications (sodium restriction, heart-healthy diet), activity guidelines, and importance of medication adherence.
   • Teach patients how to monitor for and report worsening symptoms.
   • Rationale: Patient education empowers individuals to actively participate in their care, improve adherence to treatment plans, and promote long-term cardiac health.

7. Cardiac Monitoring:

   • Continuously monitor cardiac rhythm using ECG monitoring, especially in acute settings or for patients at risk for arrhythmias.
   • Rationale: Continuous monitoring allows for prompt detection and management of arrhythmias, which can significantly impact cardiac output.

8. Educate Patient to Avoid Valsalva Maneuvers:

   • Instruct patients to avoid activities that involve straining or holding their breath (Valsalva maneuvers), such as heavy lifting or straining during bowel movements.
   • Rationale: Valsalva maneuvers can increase intrathoracic pressure, reduce venous return, and strain the cardiac muscle.

9. Implement Cardiac Rehabilitation Plan:

   • Refer patients to cardiac rehabilitation programs as appropriate.
   • Rationale: Cardiac rehabilitation programs provide structured exercise, education, and support to improve cardiovascular health, functional capacity, and quality of life, and reduce mortality in patients with cardiac conditions.

10. Anticipate and Manage Potential Deterioration:

    • Continuously monitor vital signs, level of consciousness, and symptoms for any signs of worsening condition.
    • Be prepared to alert the medical team and initiate emergency measures (e.g., resuscitation) if patient deteriorates.
    • Rationale: Patients with decreased cardiac output are at risk for cardiac arrest and other life-threatening complications. Early recognition and prompt intervention are crucial.

These nursing interventions are implemented in a coordinated and individualized manner to optimize patient outcomes and promote recovery.

Nursing Care Plans for Decreased Cardiac Output

Nursing care plans provide a structured framework for organizing and delivering patient care. Here are three example care plans for decreased cardiac output, focusing on different underlying causes or presenting symptoms.

Care Plan #1: Decreased Cardiac Output related to Bradycardia

Diagnostic Statement: Decreased cardiac output related to altered heart rate secondary to bradycardia as evidenced by heart rate of 50 bpm, dizziness, and fatigue.

Expected Outcomes:

• Patient will maintain a heart rate within acceptable limits (as determined by physician) and adequate cardiac output as evidenced by:
  • Heart rate > 60 bpm (or patient-specific target).
  • Blood pressure within patient’s normal range.
  • Absence of dizziness or syncope.
  • Improved energy levels and reduced fatigue.
• Patient will verbalize understanding of bradycardia and its management.

Assessments:

1. Monitor Heart Rate and Rhythm: Assess apical pulse rate and rhythm frequently. Monitor ECG for bradycardia and any underlying rhythm disturbances.
2. Assess for Signs and Symptoms of Decreased Cardiac Output: Monitor for dizziness, lightheadedness, syncope, fatigue, chest pain, shortness of breath, and altered mental status.
3. Identify Potential Causes of Bradycardia: Review patient’s medication history, electrolyte levels, and any underlying medical conditions (e.g., hypothyroidism, sick sinus syndrome).

Interventions:

1. Administer Medications as Prescribed: Administer medications to increase heart rate as ordered (e.g., atropine if symptomatic bradycardia).
2. Monitor for Side Effects of Medications: Assess for adverse effects of medications used to treat bradycardia.
3. Provide Education on Bradycardia and Management: Explain bradycardia to the patient and family, including causes, symptoms, and treatment plan. Educate on medication regimen and importance of follow-up.
4. Safety Precautions: Implement safety measures to prevent falls due to dizziness or syncope. Advise patient to change positions slowly.

Care Plan #2: Decreased Cardiac Output related to Fluid Overload

Diagnostic Statement: Decreased cardiac output related to altered preload secondary to fluid volume overload as evidenced by edema, jugular vein distention, and shortness of breath.

Expected Outcomes:

• Patient will achieve fluid balance and improved cardiac output as evidenced by:
  • Reduced edema.
  • Absence of jugular vein distention.
  • Improved breathing and reduced shortness of breath.
  • Stable weight and balanced fluid intake and output.
  • Blood pressure and heart rate within acceptable limits.

Assessments:

1. Assess Fluid Status: Monitor daily weight, intake and output, assess for edema (peripheral, pulmonary), and jugular vein distention.
2. Monitor Respiratory Status: Assess respiratory rate, pattern, oxygen saturation, and breath sounds for crackles or wheezes.
3. Monitor Cardiovascular Status: Monitor blood pressure, heart rate, heart sounds, and peripheral pulses.
4. Review Electrolyte Levels: Monitor serum electrolytes, especially sodium and potassium, as diuretic therapy may cause imbalances.

Interventions:

1. Administer Diuretics as Prescribed: Administer diuretics as ordered to promote fluid excretion. Monitor patient response and electrolyte levels.
2. Implement Fluid and Sodium Restrictions: Reinforce prescribed fluid and sodium restrictions. Provide education on dietary modifications.
3. Elevate Legs When Sitting or Lying Down: Encourage patient to elevate legs to promote venous return and reduce edema.
4. Monitor for Signs of Dehydration: Assess for signs of excessive fluid loss due to diuretic therapy (e.g., dry mucous membranes, decreased skin turgor, orthostatic hypotension).

Care Plan #3: Decreased Cardiac Output related to Myocardial Infarction

Diagnostic Statement: Decreased cardiac output related to altered contractility secondary to myocardial infarction as evidenced by chest pain, ECG changes, and hypotension.

Expected Outcomes:

• Patient will achieve hemodynamic stability and improved cardiac output as evidenced by:
  • Relief of chest pain.
  • Stable vital signs (blood pressure, heart rate).
  • Resolution of ECG changes indicative of ischemia.
  • Improved tissue perfusion (warm and dry skin, strong peripheral pulses).
  • Reduced anxiety and improved comfort.

Assessments:

1. Assess Chest Pain: Evaluate chest pain characteristics (location, intensity, duration, relieving/aggravating factors).
2. Monitor ECG Continuously: Monitor for ST-segment changes, arrhythmias, and other ECG abnormalities.
3. Monitor Vital Signs Closely: Monitor blood pressure, heart rate, respiratory rate, and oxygen saturation frequently.
4. Assess Peripheral Perfusion: Assess skin color, temperature, pulses, and capillary refill.
5. Monitor Cardiac Enzymes: Review serial cardiac enzyme levels (troponin) to assess for myocardial damage.

Interventions:

1. Administer Oxygen Therapy: Administer supplemental oxygen to maintain adequate oxygen saturation.
2. Administer Medications as Prescribed: Administer medications as ordered, such as:
   • Nitroglycerin: For chest pain relief and vasodilation.
   • Morphine: For pain relief and anxiety reduction.
   • Aspirin and antiplatelet agents: To prevent further thrombus formation.
   • Beta-blockers: To reduce myocardial workload and oxygen demand (if appropriate).
   • ACE inhibitors/ARBs: To manage blood pressure and improve long-term cardiac function.
3. Promote Rest and Reduce Anxiety: Provide a calm and restful environment. Administer anxiolytics as needed.
4. Continuous Cardiac Monitoring: Maintain continuous ECG monitoring and be prepared to treat arrhythmias promptly.
5. Prepare for Potential Interventions: Prepare patient for potential interventions such as percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) as indicated.

These care plan examples illustrate how nursing diagnoses, expected outcomes, assessments, and interventions are tailored to address the specific needs of patients with decreased cardiac output. Nurses play a vital role in monitoring, managing, and educating patients to optimize cardiac function and improve their overall health and well-being.

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