May 20th Lecture #2

Select All That Apply Questions

• A significant portion of the class (40%) struggled with "select all that apply" questions, which often have the highest percentage of incorrect answers. It's crucial to focus on these question types.

Assessment of Cardiovascular System

Ejection Fraction (EF)

• Normal EF: $55\%$ and above, indicating effective heart function.

• Test to find EF: Echocardiogram, a non-invasive method.

• Higher EF is generally better, reflecting stronger heart contractions.

• Lower EF indicates poorer condition. Monitor closely when:

  • $45\%$: Requires doctor's attention.

  • $35\%$ and below: Serious condition, significantly increasing the risk of dysrhythmias and decreased cardiac output.

• Low EF increases the risk of dysrhythmias, including lethal ones such as:

  • V-tach (Ventricular Tachycardia).

  • V-fib (Ventricular Fibrillation).

  • Uncontrolled A-fib (Atrial Fibrillation with RVR - rapid ventricular rate), all of which compromise effective heart function.

• Decreased cardiac output results from reduced EF, impacting overall perfusion.

Factors Influencing Cardiac Output

• Contractility: Influenced by calcium levels. Calcium plays a vital role in heart muscle contraction, but balance is crucial.

  • Calcium helps with contractility; however, too much calcium is not good for the heart muscle, leading to potential dysfunction.

  • Calcium Channel Blockers (CCB) are given for high blood pressure to manage calcium's effect on heart muscle contraction.

• Neuro (Sympathetic and Parasympathetic nervous systems):

  • Sympathetic (fight or flight): Increases heart rate, but not necessarily cardiac output. The heart's efficiency matters more than just speed.

  • Parasympathetic (vagus nerve activation): Decreases heart rate, helping to regulate cardiac output.

• Oxygenation: Insufficient oxygenation leads to high respiratory rate or low rate, both impacting cardiac function and output.

• Pathology: Heart conditions like endocarditis directly affect the heart's ability to pump effectively.

• Heart Rate:

  • Heart rate less than $50$ or greater than $150$ often results in inadequate cardiac output and a higher risk for dysrhythmias. Optimal heart rate supports effective cardiac output.

Cardiovascular Assessment

Health History

• Past medical history provides context for current cardiovascular health.

• Demographics help identify population-specific risks.

• Familial history reveals genetic predispositions to heart conditions.

• Cultural and social factors significantly influence cardiovascular health.

  • Cultural: Example: Filipinos and salty/fatty food leading to high blood pressure. Dietary habits impact heart health.

  • Social: Smoking and drinking habits are modifiable risk factors.

• Risk Factors:

  • Modifiable: Smoking, obesity, lack of exercise, diet, diabetes (Type 2). Addressing these can improve cardiovascular outcomes.

  • Non-modifiable: Age, genetics, gender (sex), Type 1 Diabetes(autoimmune). Understanding these helps tailor preventative strategies.

Cardiovascular-Specific Questions

• Chest Pain/Discomfort: Never ignore chest pain; always assess to rule out cardiac issues.

  • Differentiate between cardiac and GI issues (GERD) as symptoms can overlap.

  • In women, MI symptoms can be mistaken for GI symptoms due to smaller arteries being affected. In men it will be bigger arteries in the upper section of the heart/chest area that are affected. Recognizing these differences is crucial for timely intervention.

• Shortness of breath and difficulty breathing: Indicates potential heart or lung issues affecting oxygenation.

• Peripheral Edema: Check upper and lower extremities, trunk, periorbital edema for signs of fluid retention related to heart failure.

  • Generalized edema: Anasarca, indicates severe fluid overload.

  • Anasarca: Swelling in the face, chest, abdomen, etc; pitting edema may be present, signifying significant fluid retention.

• Weight gain (water retention): Rapid weight gain suggests fluid accumulation due to heart dysfunction.

• Abdominal distension (ascites): Fluid backs up from the right side of the heart to the venous circulation, leading to third spacing and indicating right-sided heart failure.

• Palpitations: Awareness of heartbeats, possibly indicating arrhythmias.

• Unusual fatigue: Common sign of decreased cardiac output, limiting oxygen delivery to tissues.

• Change in LOC (level of consciousness)/Confusion: Low perfusion to the brain due to impaired cardiac output.

• Medications: Understand current medications and their effects on the cardiovascular system.

• Nutrition: Assess dietary habits and their impact on heart health.

• Elimination: Related to kidney function (urinary output), reflecting perfusion status.

  • Decreased cardiac output can lead to oliguria (low urine output) due to low perfusion to the kidneys. Monitoring urine output helps assess cardiac function.

• Activity/Exercise: Assess activity levels and tolerance to exertion.

  • Exercise doesn't necessarily mean gym; 30-45 minutes of brisk walking 3-4 times a week is good for cardiovascular health.

• Sleeping/Resting: Sleep patterns can reveal cardiovascular stress.

• Sexuality/Reproduction: Cardiovascular issues can impact sexual function.

• Coping: Assess coping mechanisms related to managing cardiovascular conditions.

Physical Appearance

• Skin: Check skin color, temperature, and moisture as indicators of perfusion.

• Pulse Pressure: Difference between systolic and diastolic blood pressure, reflecting arterial health.

• Blood Pressure: Check for orthostatic changes to assess autonomic function.

  • Orthostatic Hypotension: Drop of $20$ mmHg systolic or $10$ mmHg diastolic, or a change in pulse of $20$. Orthostatic changes indicate volume depletion or autonomic dysfunction.

  • Nurse needs to assess patient during orthostatic blood pressure measurement (not CNA) for accurate assessment.

Arterial Pulses

• Assess pulses in upper and lower extremities to evaluate circulation.

• Start distally and move proximally to identify potential blockages.

• Upper Extremities: Start with radial, then brachial, then axillary.

• Lower Extremities: Start with dorsalis pedis (pedal pulse), then posterior tibialis, popliteal, femoral.

• Dorsalis Pedis:

  • Located on top of the foot.

  • Mark location with an "X" if difficult to find, especially with swelling to ensure consistent assessment.

  • If unable to palpate, use Doppler to assess blood flow.

  • Document: "Unpalpable pulse, positive Doppler," to ensure clear communication.

• Posterior Tibialis: Located near the ankle area.

• Popliteal Pulse.

• Femoral Pulse.

• If distal pulses are strong, proximal pulses will likely be strong as well, indicating good overall circulation.

Jugular Vein Distension (JVD)

• Assess at a 45-degree angle, with the patient looking sideways, to evaluate venous pressure.

• Common in heart failure patients, indicating fluid overload.

• Hard to detect if a patient is laying down; proper positioning is essential.

Heart Inspection

• Listen to heart sounds and rhythm (regular or irregular) to identify abnormalities.

• Listen for a full minute, especially if the rhythm is irregular or when checking apical pulse for specific medications to ensure accurate assessment.

• Heart Sound Areas: Aortic, Pulmonic, Tricuspid, Mitral (Apical/PMI - point of maximal impulse).

• All People Eat Time Magazine (A mnemonic for the auscultation points):

  • Aortic: Second intercostal to the right.

  • Pulmonic: Second intercostal to the left.

  • Tricuspid: fourth intercostal.

  • Mitral: fifth intercostal, left midclavicular line. The mitral area is also where you

  • During assessment check the Apical pulse for accurate heart rate measurement.

• Use the back of the hand when assessing female patients for comfort and respect.

Peripheral Signs

• Clubbing of fingers: Indicates chronic hypoxia.

• Cyanosis: Central vs. peripheral, indicating oxygenation issues.

  • Circumoral cyanosis: Around the mouth, suggests central cyanosis.

• Edema: Pitting vs. non-pitting, indicative of fluid accumulation.

  • Assess depth of depression (2mm = +1, 4mm = +2, 6mm = +3, 8mm = +4) to quantify edema severity.

• Xanthelasma: Cholesterol deposits, suggesting hyperlipidemia.

• Capillary Refill: Less than 3 seconds, assessing peripheral perfusion.

  • In thick mycotic toenails, press on the toe instead of the nail for accurate assessment.

Pulse Pressure Abnormalities

• Low Pulse Pressure: Bleeding, heart failure, indicating reduced cardiac output.

• High Pulse Pressure (above 40 mmHg): Can occur due to certain conditions, reflecting arterial stiffness.

Pulsus Paradoxus

• Correlation between pulse and respiration.

• Pulse weakens during inhalation and strengthens during exhalation, an exaggerated response.

• Seen in conditions like cardiac tamponade, where cardiac filling is impaired.

Cardiac Biomarkers (Enzymes)

• Troponin, CK-MB, and CK are key indicators of myocardial damage.

Troponin

• Troponin I and Troponin T are specific to cardiac muscle damage.

• Troponin I is more specific to myocardial injury and shows up sooner, providing early detection.

• Elevated troponin indicates myocardial injury, confirming heart muscle damage.

• High sensitivity troponin I: Elevates in STEMI (ST-elevation myocardial infarction) and NSTEMI (Non-ST elevation myocardial infarction), crucial for diagnosing acute coronary syndromes.

CK-MB (Creatine Kinase-MB)

• Specific to myocardial muscle, though less specific than troponin.

• CK-BB (brain), CK-MM (skeletal muscle) are other CK isoforms but are less relevant to cardiac assessment.

Blood Chemistry

• Hematology, Coagulation, and Lipid Profile provide insights into cardiovascular risk.

• Lipid Profile:

  • HDL (high-density lipoprotein): Good cholesterol (goal > 40 mg/dL), promoting cholesterol removal.

  • LDL (low-density lipoprotein): Bad cholesterol, contributing to plaque formation.

  • Doctors want to increase the good more to improve overall lipid balance.

• BNP (B-type Natriuretic Peptide/Brain Natriuretic Peptide):

  • Elevated in heart failure; hormone released when the left ventricle works too hard, serving as a marker of heart failure severity.

  • Normal: Below 100.

  • 300: Needs workup; high means positive heart failure.

  • Originally discovered in pig's brain.

• C-Reactive Protein (CRP):

  • Elevated indicates inflammation, but doesn't specify location, suggesting possible cardiovascular inflammation.

• Homocysteine:

  • Elevated indicates increased risk of cardiovascular diseases, peripheral vascular diseases, or stroke, affecting endothelial function.

  • Is an amino acid.

• Myoglobin:

  • Hemeprotein found in heart and skeletal muscle.

  • Sensitive indicator of early MI, though less specific than troponin.

Electrocardiography (EKG/ECG)

• 12-Lead EKG: Checks all axes of the heart, providing a comprehensive view of electrical activity.

• Continuous EKG Monitoring: 5-lead or 6-lead (telemetry unit) for ongoing rhythm surveillance.

  • Electrode Placement: White (snow) over green (mountain) on the right side (RA, RL), black and red (smoke over fire) on the left side (LA, LL), brown (chocolate) close to the heart (chest) for accurate signal detection.

• Holter Monitor:

  • Device worn by the patient to record electrical signals over an extended period.

  • Worn for 24 hours to 7 days or longer, capturing intermittent arrhythmias.

  • Patient records date, time, and activity when palpitations occur to correlate symptoms with EKG findings.

• If patient on continuous monitoring has chest pain or V tach, a 12-lead EKG may be ordered to check for heart attack, providing immediate diagnostic information.

Stress Test

• Treadmill/Exercise Stress Test: For patients who can stand and run, assessing heart function under exertion.

• Pharmacologic Stress Test: For patients who cannot exercise; medication simulates exercise, achieving similar physiological effects.

• 12 lead is done at rest, providing a baseline.

• The patient does the treadmill to increase cardiac demand and reveal ischemia.

Imaging Techniques

• MRI (Magnetic Resonance Imaging): Provides detailed anatomical and functional information.

• Myocardial Perfusion Imaging: Assesses blood flow to the heart muscle.

• PET (Positron Emission Tomography): Focuses on cancer cells but can also assess myocardial viability.

• CAT Scan (Computed Tomography):

  • Assess for allergies to shellfish/iodine and kidney function (creatinine level) before injecting dye to prevent adverse reactions.

  • Normal Creatinine: 0.6-1.2 (or up to 1.4).

  • Elevated creatinine indicates kidney problems; injecting dye can lead to renal failure. Baseline kidney function is crucial.

  • Nursing Intervention: Increased water intake to rid of dye and protect kidneys.

• MRA (Magnetic Resonance Angiography): MRI with dye injection to visualize blood vessels.

• MRI Considerations:

  • Check for metal implants, especially recent metal eye injuries, to ensure patient safety.

  • Pacemakers: Newer models can be turned off remotely; need to know the manufacturer and collaborate with MRI tech for safe imaging.

Echocardiogram

• Two Types: Transthoracic Echocardiogram (TTE) and Transesophageal Echocardiogram (TEE) to visualize heart structure and function.

• TTE (Transthoracic Echocardiogram):

  • Non-invasive; done at the bedside, making it convenient.

  • No preparation, consent, or NPO required.

• TEE (Transesophageal Echocardiogram):

  • Invasive; requires consent (obtained by the doctor) due to its nature.

  • Transesophageal: Goes down the esophagus; patient is given moderate sedation for comfort.

  • Bypasses muscles and rib cage, providing a clearer view of the heart valves and chambers and check any blood clots. Superior visualization.

Synchronized Cardioversion

• TEE may be performed before synchronized cardioversion (for A-fib with RVR) to check for clots, specially when medications don't work, reducing stroke risk.

• Cardioversion can dislodge clots, leading to stroke; pre-screening is vital.

Cardiac Catherization

• Cardiac cath/angiography/angiogram: To check for blockages in the arteries, a key diagnostic procedure.

Access

• Femoral artery (common), radial artery (less bleeding risk) are common insertion sites.

• Inject dye to illuminate arteries, enabling visualization of blockages.

• If there's a clot; perform PTCA (Percutaneous Transluminal Coronary Angioplasty) to restore blood flow.

• PTCA: Stent is placed to open up the artery, maintaining vessel patency.

• Observe the site of bleeding; closely for post-procedural complications.

Post-Procedure Care

• Bleeding is a common complication; vigilant monitoring is essential.

• Femoral Access: Bed rest for up to 6 hours; no bending or leg crossing; bedpan use to prevent bleeding.

• Radial Access