Hemodynamics Flashcards
Hemodynamics Goal
delivery of oxygen
biggest factors of hemodynamic monitoring
Hg and SaO2
normal Stroke Volume
60-120 ml/beat
What is. CVP?
volume reaching the right ventricle
What is PCWP?
indirect measure of volume left ventricle volume (uses Pulmonary Artery Catheter wedged in a branch of the pulmonary artery)
Normal preload values for right and left ventricle
R: ventricle CVP- 2-6 mmHg
L Ventricle: PCWP-6-12 mmHg
How to increase preload (5)
- Increase fluids (NS, LR): bolus
- Colloids (blood, albumin)
- Vasoconstrictors
- Anti-embolism stockings
- Elevate the legs
How to decrease preload (3)
- Decrease fluids
- Vasodilators: ex. Hydralazine
- Diuretics: ex. Furosemide
What is afterload? What is it based on?
- Pressure LV must overcome to eject stroke volume
- Based on distensibility or compressibility of arterial vessels
normal LV afterload
Systemic Vascular Resistance (SVR): 800-1200 dynes/sec/cm-3
Normal RV afterload
: Peripheral Vascular Resistance (PVR) 150-250 dynes/sec/cm-3
in afterload….increased ___= decreased __
SVR=CO
How to increase afterload (2)
- fluids
- vasoconstrictors
how to decrease afterload (2)
- fluids
- vasodilators
What is contractility dependent on?
oxygenation and electrolyte balance
How to enhance contractility
Calcium, catecholamines
How to decrease contractility
dopamine, norepinephrine, epinephrine
Determinants of SV (3)
- preload
- afterload
- contracility
stroke volume definition
blood ejected by the heart per BEAT
CO definition
volume of blood ejected each minute
CO equation
HR x SV
normal CO range
4-8 L/min
difference between CO and cardiac index
cardiac index takes into consideration the patient’s body surface area
Cardiac index equation
CO/BSA
factors causing Low CO (inadequate left ventricular filling)- 7
- Tachycardia
- Dysrhythmias
- Hypovolemia
- Mitral or tricuspid stenosis
- Pulmonic stenosis
- Constrictive pericarditis or tamponade
- Restrictive cardiomyopathy
factors causing Low CO (inadequate left ventricular ejection)-7
- CAD causing LV ischemia or infarction
- Myocarditis, Cardiomyopathy
- Increased afterload (HTN, aortic stenosis)
- Mitral regurgitation
- NEGATIVE inotropes
- Metabolic disorders
decreased perfusion fail safe mechanisms primary (skin and GI)-4
- cool, clammy, cyanotic, ashen skin
- decreased Bowel sounds
- constipation or diarrhea
- increased GI tube output
decreased perfusion fail safe mechanisms secondary (kidneys, liver, lungs)-6
- increased RR and effort
- SOB
- decreased UO
- increased BUN, creatinine, K+
- decreased GFR
- increased ALT, AST, coag times
decreased perfusion fail safe mechanisms final (brain and heart)-6
- ALOC
- slow reacting pupils
- chest pain or pressure
- tachy or bradycardia
- arrythmias
- ST elevation
Noninvasive hemodynamic monitoring-4
- MAP
- JVP
- serum lactate
- BP Cuff
map should be above……
65
What does measuring JVD estimate
CVP
What does serum lactate show?
information on end organ perfusion
Normal CVP
2-6 mmHg
Causes of increased CVP-4
- fluid overload
- cardiac tamponade
- R heart dysfunction (cor pulmonale)
- venoconstriction
causes of decreased CVP-3
- dehydration
- volume loss
- venodilaton
Arterial line monitoring nursing responsibilities
- Patient education
- Gather equipment
- Assist provider: set up pressure bag (300 mm Hg), prime tubing
- Zero/level transducer (phlebostatic axis), monitor waveform
- Dress site (Immobilize wrist, Limit flexion of hip to 30 degrees if femoral, Monitor for bleeding)
- Compare to cuff
A-line complications-4
- Air embolus
- Hemorrhage and Hematoma
- Thrombosis: keep pressure bag full and at 300 pressure
- Infection
What is Flo-Trac?
proprietary transducer added to a-line
flotrac limitations-4
Spontaneous Breathing: inaccurate SVV
Open chest
Arrythmias
However provides hemodynamic measures without the need for a PA** catheter
Pulmonary artery pressure elevation causes (5)
- Pulmonary hypertension
- Left ventricular failure
- Mitral stenosis (stiff)
- Mitral valve regurgitation (incompetent)
- Atrial or septal defect
Normal PCWP
6-12 mmHg
causes of increased PCWP-7
- fluid overload
- aortic stenosis
- aortic regurgitation
- mitral stenosis
- LV failure
- cardiac tamponade
- constrictive pericarditis
causes of decreased PCWP-2
- hypovolemia
- vasodilation
PCWP Reminders (3)
DO NOT LEAVE BALLOON INFLATED
NEVER INFLATE FOR > 10-15 SECs
Never pull back air from syringe-passive move
normal cardiac index
2.5-4.0
