Acute Cardiac Considerations in Adult Patient (part 1)

What does RAAS stand for?

Renin- Angiotensin- Aldosterone System

When is RAAs activated?

When blood pressure or blood volume is low

What organ releases renin

Kidneys

What causes the kidneys to release renin?

Low blood pressure/ low renal blood flow

what does renin act on ?

Angiotensinogen

where is angiotensinogen produced?

Liver

Angiotensinogen becomes what?

angiotensinogen I

What enzyme converts Angiotensin I to Angiotensin II?

ACE

where is ACE primarily found?

Lungs/ endothelium

What is the main effect of Angiotensin II on blood vessels?

Vasoconstriction → BP increases.

What hormone does Angiotensin II stimulate?

Aldosterone

Where is Aldosterone produced?

Adrenal Cortex

What does aldosterone make the kidneys retain?

Sodium and water

What electrolyte does aldosterone cause the kidneys to excrete?

Potassium K+

What happens to blood volume when sodium and water are retrained

Blood volume increases

What happens to blood pressure when blood volume increases?

Blood pressure increases

Hypertension:

Occurs when systolic blood pressure is at or greater than 130 mm Hg or diastolic blood pressure is at or greater than 80 mm Hg for two or more assessment of blood pressure.

Essential Hypertension:

Also called primary hypertension accounts for most cases of hypertension. There is no known cause.

Secondary hypertension:

can be caused by disease states, such as kidney disease, or as adverse effect of some medications.

Arterial Barorecptors:

located in the carotid sinus, aorta, and left ventricle. they control blood pressure by altering the heart rate. they also cause vasoconstriction or vasodilation.

Regulation of Body-fluid volume:

Properly functioning kidneys retain fluid when a client is hypotensive and excrete fluid when a client is hypertensive.

Renin-angiotensin-aldosterone system:

Renin is covered into angiotensin II, which causes vasoconstriction and controls aldosterone release, causing the kidneys to reabsorb sodium and inhibit fluid loss

Vascular autoregulation

Maintains consistent level of tissue perfusion

What can prolonged, untreated, or poorly controlled hypertension cause?

Peripheral vascular disease and organ damage, especially affecting the heart, brain, eyes, kidneys

Why does uncontrolled hypertension damage organs?

Constantly elevated pressure puts stress on blood vessel walls, eventually causing vascular damage and reducing healthy blood flow to organs.

What is left ventricular hypertrophy (LVH)?

Thickening/enlargement of the left ventricular heart muscle.

Why can hypertension cause left ventricular hypertrophy?

Hypertension increases resistance (afterload) against which the left ventricle must pump.

Hypertension Symptoms:

few of no manifestations, headaches, particularly in the morning, facial flushing, dizziness, fainting, retinal changes, visual disturbances, nocturia

Hypertension Stages:

Prehypertension: systolic 120 to 139 mm Hg; diastolic 80 to 89 mm Hg Stage I hypertension: systolic 140 to 159 mm Hg; diastolic 90 to 99 mm Hg
Stage II hypertension: systolic greater than or equal to 160 mm Hg; diastolic greater than or equal to 100 mm Hg

Hypertension diagnostics:

chest x ray, ECG

Why are BUN and creatinine checked in a client with hypertension?

To evaluate kidney function and look for kidney damage.

Elevated serum corticoids detect

Cushing’s disease

Blood glucose and cholesterol studies can identify

contributing factors related to blood vessel changes

Why are diuretics used for hypertension, and what should the nurse monitor?

They decrease fluid volume → BP decreases.

Monitor K⁺, muscle weakness, irregular pulse, and dehydration.

Which diuretics can cause low potassium (hypokalemia)?

Thiazides (HCTZ) and loop diuretics (furosemide) → increase K⁺ excretion.

How is spironolactone different from HCTZ and furosemide?

Spironolactone is potassium-sparing, so it decreases K⁺ loss and can cause hyperkalemia.

How do calcium channel blockers lower blood pressure?

They alter calcium movement through cell membranes → vasodilation → BP decreases.

What should the nurse monitor with calcium channel blockers?

Blood pressure and pulse

What is a common adverse effect for calcium channel blockers

Hypotension is common.

What serious adverse effect should the client report immediately?

Angioedema — swelling of the lips, face, tongue, or throat that can cause life-threatening airway obstruction.

what do angiotension-converting enzyme inhibitors (ACE)-pril prevent?

prevent the conversion of angiotensin I to angiotensin II, which prevents vasoconstriction.

What should the nurse monitor/teach about with ARBs?

monitor for angioedema and heart failure. Teach the client to report swollen lips/face or edema and to change positions slowly.

What electrolyte is important with ARBs, and what should the client avoid?

Monitor serum potassium because ARBs can cause hyperkalemia. Teach the client to avoid high-potassium foods.

How does spironolactone affect electrolytes and fluid?

Blocks aldosterone → retains K⁺(potassoim) and excretes Na⁺(sodium) + water.

What is the major electrolyte concern with spironolactone?

Hyperkalemia. Monitor K⁺ and avoid potassium supplements, potassium-sparing diuretics, and potassium-rich foods/salt substitutes.

What should the nurse teach about spironolactone interactions?

Avoid grapefruit juice and St. John’s wort because they can increase adverse effects.

How do beta blockers lower BP?

They decrease cardiac output and block renin release, which decreases vasoconstriction → BP decreases.

What important teaching should the nurse give a client taking a beta blocker?

Do NOT suddenly stop the medication because it can cause rebound hypertension. It can also cause fatigue, weakness, depression, and sexual dysfunction.

What is important about hypoglycemia in a client taking a beta blocker?

Beta blockers can mask tachycardia, which is normally a sign of hypoglycemia. Teach the client to recognize other signs of low blood glucose.

How do central alpha-2 agonists lower BP?

They decrease norepinephrine activity → cause vasodilation → decreased blood pressure.

What should the nurse teach when starting a central alpha-2 agonist?

Start with a low dose, usually at night, monitor BP for about 2 hours after starting, and use caution with driving until the effects are known.

What diet is recommended for clients with hypertension?

The DASH diet: more fruits, vegetables, and low-fat dairy, while decreasing sodium and fat.

What lifestyle changes can help lower BP?

Lose weight, exercise, stop smoking, limit alcohol, reduce sodium/fat, increase calcium and magnesium, and reduce stress.

What is one of the biggest diet changes for hypertension?

Decrease sodium intake and avoid foods high in sodium and fat to help lower BP.

What BP finding is associated with a hypertensive crisis?

Extremely high BP, generally SBP >240 mmHg or DBP >120 mmHg. This is a medical emergency.

What manifestations might a client having a hypertensive crisis have?

Severe headache, blurred vision, dizziness, disorientation, and epistaxis (nosebleed).

What are the nursing priorities for hypertensive crisis?

Give prescribed medications to lower BP, monitor ECG, and frequently assess neurologic status.

What is acute coronary syndrome?

A sudden severe reduction or blockage of blood flow to the heart muscle, usually from plaque rupture and clot formation.

What conditions are included under ACS?

Unstable angina, NSTEMI, And STEMI

Why is ACS dangerous?

Reduced blood flow means reduced oxygen to the myocardium, which can cause heart muscle damage or death → myocardial infarction.

What usually starts the process that causes ACS?

Atherosclerotic plaque builds up inside the coronary arteries, narrowing the vessel

What happens when a coronary plaque ruptures?

The plaque can tear/rupture → blood clot forms → coronary blood flow is greatly reduced or blocked.

What happens to the heart muscle when oxygen is blocked?

Without oxygen, myocardial cells become damaged or die, resulting in a heart attack (MI).

What is stable angina?

Chest pain that occurs with exercise or emotional stress and is usually relieved by rest or nitroglycerin.

What makes unstable angina different from stable angina?

Unstable angina can occur with exercise OR at rest and becomes more frequent, severe, or longer-lasting. Think preinfarction.

What is variant (Prinzmetal’s) angina?

It is caused by a coronary artery spasm and often occurs when the client is at rest.

What is classic chest pain associated with ACS?

Substernal/precordial crushing or aching pressure that may radiate to the shoulder, arm, or jaw.

What other symptoms can occur with ACS?

Nausea, dizziness, anxiety/feeling of impending doom, shortness of breath, tachypnea, palpitations, and diaphoresis.

What physical findings should make the nurse concerned about ACS?

Pale, cool, clammy skin; tachycardia; diaphoresis; vomiting; decreased LOC; and shortness of breath.

Which cardiac marker indicates cardiac tissue damage and is especially important for MI?

Troponin I or T. Any positive value indicates cardiac tissue damage and should be reported.

What is the timing of the cardiac enzymes?

Myoglobin = earliest marker, gone by ~24 hr.
CK-MB = peaks around 24 hr, gone by ~3 days.
Troponin = stays elevated longer (I ~7–10 days, T ~10–14 days).

What ECG changes are associated with ischemia, injury, and necrosis?

ST depression/T-wave inversion = ischemia; ST elevation = injury; abnormal Q wave = necrosis.

Why is cardiac catheterization performed?

It is an invasive diagnostic procedure used to identify the location and degree of coronary artery blockage.

What should the nurse assess before cardiac catheterization?

Keep the client NPO for 8 hours, explain the procedure, and assess for iodine/shellfish allergy because contrast media is used.

Where is the catheter inserted during coronary angiography?

Usually through the femoral artery/vessel (sometimes brachial) and threaded toward the heart while contrast is used to visualize coronary vessels.

How much oxygen may be administered for a client with ACS/angina according to the slide?

2-4L/min as prescribed

Why is oxygen given to a client experiencing cardiac ischemia?

To support oxygen delivery to the myocardium when oxygen supply is reduced.

What nursing intervention should be done along with oxygen therapy?

Promote energy conservation and cluster nursing interventions so the client does not use unnecessary energy/oxygen.

How does nitroglycerin help with angina?

It causes vasodilation, prevents coronary artery vasospasm, decreases preload and afterload, and lowers myocardial oxygen demand.

How should sublingual nitroglycerin be taken?

Stop activity and rest, then place the tablet under the tongue to dissolve. If pain isn't relieved after 5 minutes, call 911/seek emergency care.

What is a common side effect of nitroglycerin?

Headache is common because of vasodilation. Also remember the client can take up to 2 more doses at 5-minute intervals while seeking emergency help according to the instructions.

What do heparin and enoxaparin do?

They prevent clots from getting larger and help prevent new clots from forming.

What should the nurse monitor for when a client is receiving anticoagulants?

Bleeding, bruising, thrombocytopenia, anemia, and hemorrhage. Monitor appropriate labs such as aPTT/PT/INR and CBC.

What are important contraindications to anticoagulant therapy?

Active bleeding, peptic ulcer disease, history of stroke, or recent trauma are important concerns.

What do aspirin and clopidogrel do?

They prevent platelets from sticking together, which helps prevent arterial clot formation.

Why is aspirin given with nitroglycerin during chest pain?

Aspirin has antiplatelet effects and also prevents vasoconstriction, so it helps reduce the risk of clot-related coronary blockage.

What adverse effects should the nurse watch for with aspirin/antiplatelets?

Bruising and bleeding, GI upset, and tinnitus can occur. Tinnitus can be a sign of aspirin toxicity.

What is the biggest safety concern when giving morphine for chest pain?

Respiratory depression, especially in older adults or clients with respiratory conditions.

What should the nurse monitor after giving morphine?

Respiratory rate, oxygenation, BP, pain, nausea, and vomiting. Watch closely for decreased respirations and hypotension.

What are the two major types of peripheral vascular disease?

Peripheral arterial disease (PAD) and peripheral venous disease.

What is the main difference between arterial and venous disease?

Arteries carry blood AWAY from the heart, while veins return blood TOWARD the heart.

What do both types of PVD have in common?

Both interfere with normal blood flow to/from the extremities.

What causes PAD?

Usually atherosclerosis, where plaque builds up and progressively narrows the arterial lumen, reducing blood flow.

What happens to tissues when arterial blood flow decreases?

They receive less oxygen and nutrients, causing ischemia and possible tissue damage.

Where is PAD commonly found?

The arteries of the lower extremities, especially the legs.

What are major risk factors for PAD?

HTN, hyperlipidemia, diabetes, smoking, obesity, sedentary lifestyle, family history, older age, and female gender.

What is intermittent claudication?

Burning, cramping, or leg pain with exercise caused by inadequate arterial blood flow.

What position relieves PAD pain?

Resting with the legs in a dependent position can improve arterial blood flow and relieve pain.

What pulse/capillary refill changes occur with PAD?

Decreased or absent pulses and capillary refill >3 seconds.