Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
29 Cards in this Set
- Front
- Back
|
Hemodynamic equations
Blood pressure= |
Blood pressure = cardiac output X systemic vascular resistance
|
|
|
Hemodynamic equations
Cardiac Output = |
Cardiac output = stroke volume X heart rate
|
|
|
Hemodynamic equations
Cardiac Index = |
Cardiac index = CO/BSA
|
|
|
Hemodynamic equations
Mean Arterial Pressure = |
MAP = diastolic blood pressure + (1/3 systolic blood pressure - diastolic blood pressure)
|
|
|
Hemodynamic equations
SVR = |
SVR = [(MAP-CVP))/CO] X 80
|
|
|
2 factors that affect cardiac output
|
1) heart rate
2) stroke volume |
|
|
4 factors that affect stroke volume
|
1) Inotropy
2) Afterload 3) Preload 4) Lusitropy |
|
|
What is Inotropy?
|
Ventricular contractility or 'squeezing' force
|
|
|
What is Afterload? How do you quantify it?
|
Resistance or pressure that the left ventricle pumps against to eject blood into the aorta. Estimated by the SVR.
|
|
|
What is Preload? How do you quantify it?
|
Amount of tension applied to the left ventricle before contraction. Equivalent to left ventricular end diastolic volume. Estimated by pulmonary capillary wedge pressure.
|
|
|
What is Lusitropy?
|
Diastolic relaxation of the ventricle.
|
|
|
What is goal pulmonary capillary wedge pressure?
|
15-18mm Hg
|
|
|
What is goal cardiac index?
|
>2.2L/min
|
|
|
PCWP and CI in "warm and dry" patient?
|
Normal hemodynamics
PCWP <18 CI > 2.2L/min |
|
|
PCWP and CI in "warm and wet" patient?
|
Pulmonary congestion
PCWP <18mmHg CI <2.2L/min |
|
|
PCWP and CI in "cold and dry" patient?
|
Hypoperfusion
PCWP <18mm/Hg CI <2.2L/min If PCWP is <15mm/Hg remove fluid restriction or give fluids until it's between 15-18mmHg and then reassess CI |
|
|
PCWP and CI in "cold and wet" patient?
|
Pulmonary congestion and hypoperfusion
PCWP >18mm Hg CI <2.2L/min |
|
|
Signs and symptoms of congestion (8)
|
1) dyspnea
2) orthopnea, paroxysmal nocturnal dyspnea 3) rales 4) early satiety/ nausea/vomiting 5) ascites 6) hepatomegaly/splenomegaly 7) jugular venous distension 8) hepatojugular reflex |
|
|
Signs and symptoms of hypoperfusion (7)
|
1) fatigue
2) altered mental status 3) cold extremities 4) worsening renal function 5) narrow pulse pressure 6) hypotension 7) hyponatremia |
|
|
Therapy of choice after diuretics? Contraindications?
|
Vasodilators.
Hypotension is the major limiting factor preventing use of these drugs. |
|
|
Three vasodilators used in acute decompensated heart failure?
|
Sodium Nitroprusside
Nesiritide IV nitroglycerin |
|
|
Sodium Nitroprusside
MOA |
balanced arterial and venous dilation
use limited if hepatic or renal dysfunction |
|
|
Sodium Nitroprusside
Dosing |
begin: 0.3-0.5mcg/kg/min
titrate up: by 0.5mcg/kg/min max: 3mcg/kg/min |
|
|
Sodium Nitroprusside
Use limited by... |
Cyanide hepatically eliminated, thiocyanate renally excreted...so buildup of toxic byproducts if either present
|
|
|
Nesiritide (Natrecor)
Clinical effects |
vasodilation, some diuretic action, increased sodium excretion
|
|
|
Nesiritide (Natrecor)
Dosing |
Bolus: 2mcg/kg, then 0.1mcg/kg/min
Titrate up by 0.05mcg/kg/min Max: 0.3 mcg/kg limit |
|
|
Nesiritide (Natrecor)
Use limited by.... |
expense, severe hypotension (SBP <90), has a long (20 minute) half life, so if pressure drops too low will be a couple of hours before drug is gone
|
|
|
IV nitroglycerin
Clinical effects |
preferential venous vasodilator
|
|
|
IV nitroglycerin
Dosing |
5mcg/min
Titrate upward by 5mcg/min Max 200mcg/min |
