Medications and Hemodynamics (Powerpoint 2)

Question 1

on the CVP waveform, what do “a”, “c” and “v” waves represent?

It is important to remember that….
And a helpful trick to find the waves is…

Answer 1

a = atrial contraction
c = closure of tricuspid valve
v = atrial filling
Mechanical events will follow electrical.
Look for the “R” wave on the ECG. Right before it is the atrial contraction, or “a” wave.

Question 2

What can cause higher “a” waves on the CVP waveform?

Answer 2

atrial stenosis

dyssynchrony with ventricles –> RA contracting against a closed tricuspid valve.

Question 3

What will cause the absence of “a” waves on the CVP waveform?

Answer 3

atrial fibrillation –> low atrial pressures

Question 4

What will cause large “v” waves on the CVP waveform?

Answer 4

Noncompliant atria
Tricuspid regurg
Ventricular ischemia/failure.

Question 5

Normal stroke volume

Answer 5

60-100 mL/beat

Question 6

Formula for stroke volume?

Answer 6

SV = CO/HR x 1000

Question 7

Normal SVI?

Answer 7

33-44 mL/beat/m^2

Question 8

Normal SVR

Answer 8

800-1200

Question 9

What is the cause of low HR?

Answer 9

Ischemia to the RCA. (Remember, RCA supplies SA and AV nodes)

Question 10

What is the effect of glycopyrrolate

Answer 10

It is an anticholinergic that inhibits the parasympathetic nervous system, increasing the HR.

Question 11

What are the benefits of slower HR?

Answer 11

Inproved coronary perfusion, increased filling, decreased myocardial oxygen demand

Question 12

Where are the Beta-1 Receptors? What do they do?

Answer 12

Located in the heart, when stimulated, the beta-1 receptors increase HR and contractility.

Question 13

Where are the Beta-2 receptors located? What do they do?

Answer 13

Beta-2 receptors are located in the lungs and arteries of skeletal muscles. When stimulated, they cause bronchodilation and vasodilation of skeletal muscle.

Question 14

Where are the alpha-1 receptors? What do they do?

Answer 14

Alpha-1 receptors are located on the vascular smooth muscle. When stimulated, they cause vasoconstriction.

Question 15

ESMOLOL
What receptors does it act on?
What is the half life?
Time of onset?
Loading dose?
Effects on CO, BP, HR, MVO2 and PAP?

Answer 15

B1 receptors, B2 at higher doses.
9 minutes
1-2 minutes
LD 500 mg/kg
Decreases CO, BP, HR, MVO2 and PAP

Question 16

METOPROLOL
What receptors does it act on?
What is the half life?

Answer 16

B1 blocker, B2 at higher doses.

1/2 life is 3-4 hours, maximal response in 20 min.

Question 17

AMIODARONE
Indication?
Mechanism of action?
Effect on SVR and CO?
What does it do to digoxin and coumadin levels?

Answer 17

Indication - ventricular/atrial dysrhythmias
It increases conduction time in cardiac cells
Decreases the SVR, Increases CO
Increases dig and coumadin levels

Question 18

DIGOXIN
Useful in what type of patient?
Adverse drug reaction?
Effect on HR, CVP, PAOP, SVR and CO?

Answer 18

Useful in patients with AF and CHF (because it decreases AV node dysfunction and increases contractility.)
ADR: Hyperkalemia, toxicity, heart block
Lowers HR, CVP, PAOP and increases SVR and CO.

Question 19

Why does the PAD matter?

Answer 19

It is an indirect measure of LVEDP.

Question 20

Normal PAD?

Answer 20

8-12 mmHg

Question 21

Which type of dysrhythmia increases with age? (Atrial or ventricular?)

Answer 21

Atrial dysrythmias are more common with age due to atrial remodeling. Ventricular dysrhythmias are caused by ischemia, reperfusion, or electrolyte disorders and are unrelated to age.

Question 22

Is hypothermia used during off-pump CABG?

Answer 22

No

Question 23

What is the benefit of off-pump CABG?

Answer 23

Incidences of cognitive impairment are lower with off-pump CABG.

Question 24

Why does massive blood transfusion cause hypocalcemia?

Answer 24

Citrate (a preservative) in blood transfusions binds to the calcium in the transfusion.

Question 25

In a patient with tension pneumothorax, how will the pulmonary pressures be?

Answer 25

Elevated PAD and PAS

Question 26

What is PVR? PVR normal values

Answer 26

PVR is the afterload of the RV

< 250

Question 27

aldosterone

Answer 27

a steroid hormorne that assists in the conservation of Na+

Question 28

SvO2

Answer 28

average saturation of O2 in venous blood (also said as the O2 left in blood after circulation to the tissues.)
normal is 60-80.

Question 29

scvo2

Answer 29

measurement of O2 in venous blood in the SVC (reflects head and upper body)

Question 30

Normal hematocrit

Answer 30

Male 38-48

female 35-45

Question 31

clevidipine

Answer 31

decreases BP and SVR (arterial vasodiliator)

Question 32

nitroglyclerin

Answer 32

venous dilator (decreases preload)

Question 33

when should the nurse get an atrial electrogram?

Answer 33

when there is a tachycardia of unknown origin (SVT)

It is performed using the epicardial wires.

Question 34

What are signs of tamponade?

Answer 34

EQUALIZED INTRACARDIAC PRESSURES!
High/Equalized CVP, PAD, PAOP

also, High HR, low CO/CI, highPAP, High CVP

Question 35

How many times should defibrillate before starting CPR?

Answer 35

3x

Question 36

Signs of RV failure?

Answer 36

High CVP, low CO, decreased/normal PAP/PAOP.

Question 37

Signs of LV failure

Answer 37

Low CO/hypotension, tachycardia, elevated PAP/PAOP