cardiac function and infective endocarditis

Question 1

What is cardiac output (CO)?

Answer 1

Blood ejected by a ventricle in 1 minute

Question 2

What is stroke volume (SV)?

Answer 2

Volume of blood pumped out of one ventricle in one contraction

Question 3

What is preload?

Answer 3

Volume of blood in ventricles at end of diastole (filling period) / End diastolic pressure

Question 4

What increases preload?

Answer 4

Hypervolemia, regurgitation of cardiac valves, heart failure

Question 5

What is afterload?

Answer 5

Force required to eject blood from ventricles / resistance left ventricle must overcome to circulate blood

Question 6

What increases afterload?

Answer 6

Hypertension (HTN), vasoconstriction

Question 7

What happens when afterload increases?

Answer 7

Increased cardiac workload

Question 8

What is infective endocarditis (IE)?

Answer 8

A disease of the innermost layer of the heart and heart valves, disproportionally impacting AVs and MVs

Question 9

Pathophysiology of infective endocarditis?

Answer 9

Bacteria or fungi in the blood damage valves and endothelial surfaces → vegetation on leaflets → valves cannot pump properly → infected valves shower septic emboli → MODS risk from impaired O2 delivery

Question 10

Common etiologies of IE?

Answer 10

IV drug use, poor dentition, valve replacement surgery

Question 11

Why does IV drug use cause IE?

Answer 11

May not have access to clean needles → bacteria enter bloodstream

Question 12

Why does poor dentition cause IE?

Answer 12

Rotten teeth, cavities, meth use → bacteria enter bloodstream

Question 13

Why does valve replacement increase IE risk?

Answer 13

Bacteria can colonize prosthetic valve area

Question 14

What are the 2 types of IE progression?

Answer 14

Acute and Subacute

Question 15

Describe acute infective endocarditis.

Answer 15

Affects healthy valves, rapid progressive illness, not always related to valve replacement/disease

Question 16

Describe subacute infective endocarditis.

Answer 16

Affects preexisting valve disease, develops over months (up to 6)

Question 17

Common clinical manifestations of IE?

Answer 17

Fever/chills, weakness, malaise, fatigue, anorexia, weight loss, arthralgias/myalgias, mental status changes

Question 18

What imaging might show evidence of septic emboli?

Answer 18

CT or MRI

Question 19

What is a classic sign of IE seen under nails?

Answer 19

Splinter hemorrhages in nail beds

Question 20

What is petechiae?

Answer 20

Small red dots on skin

Question 21

What heart sound change is classic for IE?

Answer 21

New or worsening systolic murmur

Question 22

Why does IE cause a murmur?

Answer 22

Bacteria/fungus on valves prevents proper closure → whooshing sound

Question 23

What are Osler’s nodes?

Answer 23

Painful, red or purple tender lesions on fingertips/toes (classic sign)

Question 24

What are Janeway lesions?

Answer 24

Flat, painless, small red spots on fingers, palms, toes, soles (classic sign)

Question 25

What are Roth’s spots?

Answer 25

Hemorrhagic retinal lesions seen with ophthalmoscope

Question 26

Why does IE cause HF?

Answer 26

Valves cannot close → blood backs up

Question 27

What ECG changes occur in IE?

Answer 27

AV blocks (1st, 2nd type I, 2nd type II, 3rd degree)

Question 28

Key diagnostics for IE?

Answer 28

H&P, blood cultures, WBC, CRP, ESR, TEE, CT chest, Duke criteria

Question 29

What should be asked in H&P for suspected IE?

Answer 29

IV drug use? Dentist visits? Preexisting heart conditions/surgeries?

Question 30

Why are 3 blood cultures drawn in IE?

Answer 30

To detect bacteria/fungus from different sites, increase accuracy

Question 31

How are IE blood cultures drawn?

Answer 31

Three cultures over an hour from three different sites, usually 15–20 min apart

Question 32

What lab values are elevated in IE?

Answer 32

WBC, CRP, ESR

Question 33

What imaging is most specific for valve vegetation?

Answer 33

Transesophageal echocardiogram (TEE)

Question 34

What is the Duke Criteria used for?

Answer 34

Diagnosis of infective endocarditis

Question 35

Prophylactic treatment is given to who?

Answer 35

High-risk patients (e.g., history of IE, prosthetic valves)

Question 36

What is the main medical treatment for IE?

Answer 36

Long-term targeted antibiotic therapy (4–6 weeks) based on culture results

Question 37

When are blood cultures repeated in IE?

Answer 37

Every 24–48 hrs until infection clears

Question 38

What device is placed for long-term IV antibiotics?

Answer 38

PICC line

Question 39

When is valve replacement surgery indicated in IE?

Answer 39

1. Valve dysfunction → heart failure, 2. Cleared infection but valve not closing, 3. Prevent embolization, 4. Uncontrolled infection

Question 40

In which cases is surgery most common?

Answer 40

Fungal IE, prosthetic valve IE (antibiotics less effective)

Question 41

Nursing assessments for IE?

Answer 41

Monitor for HF, dysrhythmias, stroke (emboli), perfusion changes in fingers/toes

Question 42

What does poor perfusion in fingers/toes suggest?

Answer 42

O2/CO2 exchange affected by IE

Question 43

What nursing interventions help IE patients?

Answer 43

Maintain tissue perfusion, maintain normal temperature, monitor for complications

Question 44

Education for IV drug use patients with IE?

Answer 44

Discuss rehab options

Question 45

General patient education for IE?

Answer 45

How IV drugs/poor dentition cause IE, signs/symptoms of reinfection, prophylactic antibiotics before surgery (esp. dental), reducing reinfection risk

Question 46

How to know if an IE patient is improving?

Answer 46

Negative/clearing blood cultures, decreased murmur, fever gone, WBC improving

Question 47

How to know if an IE patient is worsening?

Answer 47

Signs of sepsis, poor perfusion worsening, vital signs unstable