Preoperative Assessment Of The Cardiac Patient

Front 1

What are common variables associated with increases in risk for cardiac surgery

Back 1

-age,
-female gender
-LV function
-body habitus
-Redo
-Type of surgery
-Urgency

Front 2

What test is the gold standard for determining whether or not Cardiac surgery is indicated

Back 2

coronary angiography

Front 3

cardiovascular stress testing used to assess pt's cardiac function

Back 3

coronary angiography

Exercise EKG

Nonexercise (pharm) stress test

Dipyridamole thallium scintigraphy

Dobutamine stress echo

Front 4

What are indications for myocardial perfusion imaging

Back 4

-risk stratification
-myocardial viability assessment
-preop eval
-evaluation after percutaneous coronary intervention or coronary artery bypass grafting

-monitoring medical therapy in CAD (stress test q 2-3 years)

Front 5

Exercise EKG:

in pt's with a normal baseline ECG without hx of CAD, the exercise response is abnormal in up to _______%

Back 5

25%

Front 6

Mean sensitivity is ____% and specificity is ___% for single vessel disease

Back 6

68% and 77%

Front 7

For detection of multivessel disease:

sensitivity =
Specificity =

Back 7

sens = 81%

Spec = 66%

Front 8

for detection of 3 vessel or left main CAD:

sensitivity =
Specificity =

Back 8

sens = 86

spec = 53

Front 9

type of test indicated for those who have limited exercise tolerance

Back 9

nonexercise (pharm) stress test

Front 10

Type of stress test that can increase myocardial oxygen demand

Back 10

nonexercise stress test with dobutamine

Front 11

type of stress test that can produce coronary vasodilation leading to coronary redistribution

Back 11

dipyrimadol/adenosine nonexercise stress test

Front 12

blocks adensoine reuptake and increases adenosine concentration in the coronary vessels

Back 12

dipyidamole-thallium scintigraphy

Front 13

______ is a direct coronary vasodilator

Back 13

adensoine

Front 14

with this type of stress test, flow is distributed to areas distal to normal coronary arteries, with minimal flow to areas distal to coronaries that are stenotic

Back 14

dipyidamole-thallium scintigraphy

Front 15

Dipyidamole-thallium Scintigraphy...

1. normal myocardium shows up on initial imaging. dye is then injected

2. Areas of myocardial necrosis or ischemia "distal" to a coronary defect show up as a defect.

3. after delay of several hr's, dye is injected a 2nd time.

4. those initial defects show up as old scar.

5. those defects that show up as normal on subsequent imaging are consistent with areas of increased risk for MI

Back 15

......
if it is a defect that persist = scar

if is is a defect that goes away then comes back = ischemia

Front 16

Involves the infusion of dobutamine to identify new or worsening wall motion abnormalites detected by ECHO

Back 16

dobutamine stress ECHO

Front 17

The "dobutamine stress echo" has the same accuracy as?

Back 17

dipyridamole thallium

Front 18

What are the advantages of Dobutamine stress ECHO when compared to a Thallium study

Back 18

Dobutamine stress Echo:

-can assess LV fx and valves
-lower cost
-no radiation
-immediate results!

Front 19

Pre-op assessment of REDO surgery:

- can often result in?

Back 19

increased blood loss as reoperation through previous sternotomy can be bloody

Front 20

What is a big concern with prior neck surgery or ESRD

Back 20

ESRD-many times have difficult central venous access....also hx of greenfield filters

Front 21

What things should you look for on labs

Back 21

look for anemia, low platelets, BUN, Cr, and coags

Front 22

What are we most interested in when doing a coronary angiogram

Back 22

Ejection fraction

also can look at:

-stenosis of coronaries
-stenosis of subclavian artery
-valve abnormalities

Front 23

EF of ______% or greater with normal valve fx is normal

Back 23

50% or greater

Front 24

EF of less than _______% reflects a moderate reduction of ventricular function

Back 24

less than 50%

Front 25

Poor cardiac fx relates to an EF below ______%.

What might these pt's have?

Back 25

less than 30%, may have AICD

Front 26

What added risk do patients have who are diabetic and take NPH insulin

Back 26

added risk of allergic reaction to "protamine"

Front 27

cause dose dependent depression of contractile function

Back 27

volatile agents

Front 28

what 2 volatile agents exert equal but more potent myocardial depression than iso, des, or sevo

Back 28

halothane and enflurane

Front 29

Halothane, enflurane, sevoflurane have what effect on epinephrine

In what order do they affect it?

Back 29

they lower the arrhythmogenic threshold for epinephrine

Halothane>enflurane>sevo+des

Front 30

They are mild direct coronary vasodilators

Back 30

volatile anesthetics

Front 31

What 2 gases cause decreases in SV and CO

Back 31

halothane and enflurane

Front 32

What gases cause a decrease in SVR

Back 32

ISO, SEVO, DES

Front 33

**What volatile anesthetics attenuate the baroreceptor reflex

Back 33

they all do

Front 34

How does Thiopental effect the heart

Back 34

decreases contractility and increases HR

(has direct negative inotropic action)

Front 35

In large doses when given rapidly, thiopental will have what effect

Back 35

causes myocardial depression

minimal effects when given slowly

Front 36

Who would you want to avoid Thiopental with

Back 36

avoid in those with LV or RV failure, tamponade, and hypovolemia

Front 37

Versed can cause a decrease in MAP of _% and increase in HR of ____%

Back 37

20% and 15%

Front 38

The combination of versed and _____ cause less CV depression, more amnesia, and less postop somnolence compared to thiopental

Back 38

versed and ketamine

Front 39

What drug has a saftey margin 4 times greater than thiopental

Back 39

etomidate

Front 40

What drug can decrease BP or CI in patients with valvular heart disease

Back 40

Etomidate

Front 41

What is an excellent induction drug for someone who has cardiac tamponade

Back 41

ketamine; maintains CI!!, and increases BP, SVR, and RAP

Front 42

What are the disadvantages to using propofol in cardiac surgery

Back 42

diastolic and MAP drop

SVR, CI, SV fall

Front 43

High dose morphine was shown to be successful with?

Back 43

vavular heart disease...

unsuccessful in cardiac surgery

Front 44

What Opioid has shown to be most reliable for valve and cardiac surgery?

Back 44

fentanyl

Front 45

What is the major advantage of fentanyl?

Back 45

lack of cardiovascular depression

Front 46

Fentanyl has been known to cause HTN and tachycardia in what 3 procedures

Back 46

-pericardiectomy
-aortic root dissection
-sternotomy

Front 47

What are the 4 effects of cardiopulmonary bypass?

Back 47

Hemodilution

Reduced blood flow (decreases metabolism)

Hypothermia (reduces liver and renal enzyme fx...decreasing metabolism)

Sequestration (lungs, CPB circuit)

**the reduced blood flow and hypothermia both increase effects of drugs**