Cardiac Flashcards
What is preload?
The amount of blood returning to the right side of the heart AND the muscle stretch that the volume causes.
What is released by the atria in response to preload stretch?
ANP
What is afterload?
The pressure in the aorta and peripheral arteries that the left ventricle has to pump against to deliver blood to the body. High after load decreases cardiac output.
What is stroke volume?
The amount of blood pumped out of the ventricles with each beat.
What is cardiac output?
The amount of blood delivered by the heart to perfuse the body. CO = SV X HR
What are some medications that reduce preload?
Diuretics (furosemide) and Nitrates (nitroglycerin). They vasodilate (nitrates) or diverse to reduce preload.
What are some medications that decrease afterload?
ACE inhibitors (“pril”), ARBS (“sartan”), hydralazine, nitrates (nitroglycerin). They vasodilate to decrease after load.
What are medications that improve contractility?
Inotropes (dopamine, dobutamine, milrinone)
What are medications that control cardiac rate?
Beta blockers (“lol”), calcium channel blockers (diltiazem, verapamil, amlodipine), digoxin
What are medications that control rhythm?
antiarrhythmics (amiodarone)
What are the 3 arrhythmias that are always a big deal?
1) pulseless ventricular tachycardia
2) ventricular fibrillation
3) asystole
What is the most common type of cardiovascular disease?
Coronary Artery Disease (CAD). This is a broad term that includes chronic stable angina and acute coronary syndrome.
What causes Chronic Stable Angina?
Intermittent/decreased blood flow to the myocardium leading to ischemia.
What brings on the pain of chronic stable angina?
Low 02 usually brought on by exertion.
What relieves the pain of chronic stable angina?
Rest and/or nitroglycerin SL
How is nitroglycerin given and how often?
sublingually (do not swallow), every 5 minutes for a max of 3 doses. May cause headache.
What medication must be kept in a dark glass bottle and be kept dry and cool?
Nitroglycerin
What does nitroglycerin do?
Causes venous and arterial dilation, decreasing preload and afterload and increasing blood flow to the heart. May cause headache.
What happens to the BP after nitroglycerin is given?
It drops
What is used for prevention of angina?
Beta blockers, calcium channel blockers, aspirin
What do beta blockers do?
They block beta cells, which are receptor sites for catecholamines (epinepherine and norepinephrine) which causes reduction in BP, HR, and myocardial contractility. This decreases cardiac workload BUT it can also decrease cardiac output!
note always assess BP and HR before administration of beta blockers!
What do calcium channel blockers do?
They block calcium receptor channels in smooth muscle. By prohibiting the entry of calcium (which stimulates muscle contraction) the smooth muscle relaxes, causing vasodilation of the arteries. This decreases afterload and increases oxygen to the heart muscle.
What kind of exercise should those with unstable angina avoid? What should they use?
Avoid isometric exercises (weight lifting) and walk. Do everything possible to REDUCE workload of the heart!
What is a cardiac catheterization?
Catheter inserted in artery or vein for diagnostic and treatment purposes.
What is an important question to ask before a cardiac Cath?
Allergic to iodine or shellfish? The dye used during the procedure is iodine based.
Check ____ before a cardiac cath?
Kidney function. The dye is excreted through the kidneys. If there is kidney problems, acetylcysteine may be given to protect kidneys.
Why is the injectable dye used for a cardiac cath called a “hot shot”?
Causes warmth/flushing and palpitations.
What are the 5 “P”s to assess on extremity distal to the puncture site for post-op cardiac cath patients?
1) Pulselessness
2) Pallor
3) Pain
4) Paresthesia
5) Paralysis
After a cardiac cath, what are post-op procedures?
Bleeding precautions, bed rest, flat position with extremity kept STRAIGHT for 4-6 hours.
What should be reported ASAP after a cardiac cath?
Pain, It could be a hematoma forming.
Hold what medication for 48 hours post-op for cardiac cath?
Metformin (worried about kidneys)
What is Acute Coronary Syndrome?
Includes acute illness like MI and unstable angina. These conditions result in both ischemia and NECROSIS (unlike chronic angina)
Is pain caused by unstable angina relieved by rest or nitro?
No
What is the goal during acute coronary syndrome (MI, unstable angina)
Limit the infarction size!
What is the #1 sign of impending MI in the elderly?
shortness of breath
Women usually present with what kind of symptoms, indication MI?
GI symptoms, epigastric discomfort, pain between the shoulders, aching jaw
STEMI clients are the most worrisome, what is the goal of care?
Get them to the cath lab for a PCI in less than 90 minutes.
What is the most specific bio enzyme to assess for MI?
Rising troponin levels.
How soon does troponin elevate and how long does it stay elevated?
3-4 hours, up to 3 weeks
What cardiac enzyme elves within 3-6 hours and peaks in 12-24 hours?
CPK-MB. This enzyme is often used to assess a new MI after a recent one which cause a rise in troponin that has not yet decreased.
Myoglobin is a non-cardiac specific enzyme that increases and peaks when?
Increases within 1 hour, peaks in 12 hours. A negative result means no acute MI.
If defibrillation is unsuccessful on a client in v-fib, what is the first medication given?
Epinephrine
What anti-arrythmic drugs are given to prevent a second episode of v-fib?
Amiodarone or lidocaine.
Amiodarone can cause what?
Hypotension, which can lead to asystole.
What is the major sign of lidocaine toxicity?
Neuro changes.
What mediations are used in the ER for chest pain? What order are they given?
Oxygen, aspirin (chewable), nitroglycerin, morphine. In that order.
think MONA (but not in that order)
give descending by body part:
O2 in nose
Chewable aspirin in mouth/teeth
Nitro UNDER tongue (so nitro given under aspirin)
Morphine IV or IM in arm
When giving thrombolytics, should you give through the jugular?
No, they must be given through a site that can be compressed in case of uncontrolled bleeding.
When are thrombolytics contraindicated?
With intracranial neoplasm, intracranial bleed, suspected aortic dissection, or internal bleeding. Avoid any situation that involves bleeding!
What are bleeding precautions?
Assess for bleeding gums, hematuria, black stools, use electric razor, soft toothbrush and do NOT give IMs.
Are ABGs drawn on a client receiving thrombolytics?
No, arteries really bleed!
What is PCI?
Percutaneous Coronary Interventions. Includes percutaneous trans luminal coronary angioplasty and stents.
What is a major complication of PCI?
Myocardial Infarction
What to do if chest pain experienced after PCI?
Call provider, may be reoccluding!
What is Coronary Artery Bypass Graft (CABG)?
Open heart surgery to repair multiple vessel disease or left main coronary artery occlusion.
What is the Widow Maker?
Left main coronary artery occlusion. Causes sudden death.
What is the leading cause of heart failure?
Hypertension
Left-sided heart failure will present as what?
Lung related S/S. Left = lungs. Blood flow backs up into the lungs.
Right-sided heart failure presents as what?
Venous system S/S like distended neck veins, edema, enlarge organs, weight gain and ascites.
What are some causes of right-sided heart failure?
COPD, pulmonary embolism
What lab test is used to diagnose HF?
B-type natriuretic peptide (BNP) which is secreted by the ventricles when volume and pressure is increased.
What is the Swan-Ganz?
A balloon flotation catheter that is floated in to the right side of the heart and pulmonary artery to measure hemodynamic pressures and CO and provide access to mixed venous blood sampling.
What is the medication of choice for HF?
ACE inhibitors. They prevent the conversion of Angiotensin I to Angiotensin II which results in arterial dilation and increased SV.
What is a second medication choice for HF?
ARB’s. Beta blockers may also be used.
What should be watched for during administration of ACE inhibitors and ARBs?
Hyperkalemia. ACE inhibitors and ARBs both block aldosterone, which causes a loss of Na+ and H2O and retention of K+.
When is Digoxin given?
When clients are in sinus rhythm or a-fib and have accompanying HF. It increases the strength of cardiac contractions, slows the HR and increases CO.
What is one goal for all HF patients?
Diuresis. HF patients cannot handle extra fluid volume
What must be assessed before administration of digoxin?
Apical pulse
What are signs of digoxin toxicity?
Anorexia, nausea/vomiting, arrhythmias and vision changes (late signs) usually of halos or yellow color.
Which electrolyte imbalance is the most problematic for digoxin?
Hypokalemia.
Fluid retention think ____?
Heart problems
What is loss of capture?
No cardiac contraction follows the stimulus. This is scary!
What is failure to sense?
Pacemaker fires at inappropriate times.
Restless/anxiety think ___?
Hypoxia!
What is the priority treatment for pulmonary edema?
High flow oxygen
What are S/S of pulmonary edema?
Sudden onset, breathless, restless/anxious, severe hypoxia, productive cough (pink and frothy)
Who is at risk for pulmonary edema?
Very young and old, anyone receiving IV fluids fast, patients with history of cardiac or renal disease
What medications are given for pulmonary edema?
Diuretics, nitroglycerine, morphine, nesiritide (remember to discontinue 2 hours prior to drawing BNP labs and only use short term, no more than 48 hours), position UPRIGHT
Why is furosemide given slowly by IVP?
To prevent hypertension and ototoxicity.
What is cardiac tamponade?
Blood, fluid or exudates have leaked not the pericardial sac resulting in compression of the heart.
What puts a patient at risk for cardiac tamponade?
Right ventricular biopsy, MVC, MI, pericarditis, or hemorrhage post CABG.
What are S/S of cardiac tamponade?
Beck’s triad (hypotension, JVD, and muffled heart sounds), increased CVP, pressure in all 4 chambers is the same, shock, narrowed pulse pressure (difference between systolic and diastolic pressures)
Think ___ with narrowed pulse pressure?
Cardiac tamponade
Think ____ with widened pulse pressure?
Increased Intracranial Pressure
What is the treatment for cardiac tamponade?
Pericardiocentesis to remove blood from around the heart.
What is the hallmark sign of arterial disorders?
Intermittent claudication (pain during use/movement that is relieved by rest)
What are S/S of arterial disorders?
Coldness/numbness, decreased peripheral pulses (priority assessment), atrophy, bruit, skin/nail changes, ulcerations. Pain at rest means severe obstruction!
You ____ vein problems and ____ artery problems.
Elevate Veins (eleV(ein)ate) "V" for "vein" Dangle Arteries (dA(arteries)ngle) "A" for "arteries"
Think ___ with vein problems?
DVTs. Venous problems are not about oxygen.
What are pulses like in chronic arterial insufficiency vs chronic venous insufficiency?
In CAI they are decreased or may be absent, in CVI they are normal but may be difficult to palpate due to edema.
What is skin color like in chronic arterial insufficiency vs chronic venous insufficiency?
In CAI the limbs are pale when elevated and red when lowered. In CVI they are normal or may see petechia or brown pigmentation.
Is edema present in chronic arterial insufficiency?
Usually not, but if present then is mild. Edema is present in chronic venous insufficiency.
In which condition is gangrene a concern?
Chronic arterial insufficiency
Is compression used for chronic arterial insufficiency?
No! But it is used for CVI.
