Hemodynamics #6 Flashcards Preview

A+ Test Prep > Hemodynamics #6 > Flashcards

Flashcards in Hemodynamics #6 Deck (16):
1

Cardiac index

Make CO relative to body size
CI = CO / BSA
Normal: 2.5-4.2 LPM

2

Normal SV

60-135 ml

3

Stroke volume and ejection fraction

SV - 2/3 end diastolic volume
-thus normal ejection fraction (EF) - 67%
-EF >55% is ok

4

How do we decrease preload?

Vasodilators (immediate)
Morphine (immediate)
Diuretics (fast)
Ace inhibitors (slow)

5

How is preload increased?

Monitored by CVP or PCWP
Fluids (immediate)
Vasoconstrictors (typically fast)
-Levophed (arterial)
-neosynephrine (venous side)

6

Cardiac output

HR x SV

Normal is 4-8 LPM

7

Normal PVR
-PVR increases & decreases

50-250 dynes
Decrease with dehydration & RV failure
-increased w/ anything that causes pulmonary HTN

8

Normal SVR
-Increases & decreases

800-1200 dynes
-decreases w/ dehydration, distributive shock, vasodilators (Nitroprusside, low dose dopamine, nitro)
-increase w/ IHSS, HTN, vasoconstrictors, shock states.

9

IHSS

Idiopathic Hypertrophic Subaortic Stenosis.
-fat septum - hypertrophic cardiomyopathy => fat septum will not allow aortic valve to open => LV cannot clear

10

Medications to decrease afterload

-Nitroprusside (nitrate donor) - nitric oxide most potent vasodilator
-fenoldopam (corlapam) - dopamine agonist / vasodilate mesenteric
-nifedipine (procardia), nicardipine (Cardene) Ca channel blockers
-dobutamine (Dobutrex) - B2 / B1 agonist
-nesirtide (natrecor) RAA inhibitor, synthetic BNP

11

Medications to increase afterload

-Dopamine - A1 agonist (high doses) / significant beta activity as well
-Phenylephrine (Neo-synephrine) pure A1 agonist, will not Improve pump problems.
-norepinephrine (Levophed) A1 agonist above 2 mcg/min, don't use with pump problems.
-epinephrine A1/B1/B2

12

Dopamine robs:

Robs preload, decreases diastolic filling time, increases myocardial oxygen demand.

13

Contractility increases by which actions?

-sympathetic stimulation
-increases calcium levels (IV Ca considered especially w/ trauma)
-cardiac glycosides (digitalis)
-B1 agonists (dobutamine (#1), epinephrine)

14

Contractility is decreased by which mechanisms?

Electrolyte abnormality
-primary four: potassium, Magnesium, phosphorous, calcium

Hypoxia,

Acidosis
-correct shock states, oxygenation, bicarbonate

15

#1 cause of dampened waveform (hypodynamic)

Air in the line

16

Advanced line monitoring priorities

1. PA Cath (for risk of inadvertent wedge & embolism)
2. A-lines
3. CVP