Cardiac Pressures Flashcards
Central Venous Pressure (CVP)
A measure of the pressure exerted by fluid in the right atrium; indicative of right sided heart function
CVP
0-6
Mean Arterial Pressure (MAP)
SPP +2 (DBP)/3
Indicates the average driving force in the arterial system throughout the cardiac cycle; when available, the MAP should be used in hemodynamic assessment in decision making
MAP
70-100
Pulmonary Artery Pressure (PAP)
A measure of the systolic and diastolic pressures in the pulmonary artery
PAP is elevated in conditions that cause an increase in the amount of fluid in the pulmonary artery of conditions that decrease the elasticities of the pulmonary artery (hypervolemia, pulmonary hypertension)
PAP is decreasing conditions that cause a decrease in the amount of fluid in the pulmonary artery (hypovolemia)
PAP
Systolic: 15-25
Diastolic: 5-15
Pulmonary Capillary Wedge Pressure (PCWP) or Pulmonary Artery Occlusion Pressure (PAOP)
Is a measure of the pressure in the left ventricle at end of diastole; indicative of left sided heart function;
PCWP is increasing conditions that increase the pressure in the left ventricle at the end of diastole (increased fluid, decreased elasticity of the ventricle)
PCWP is decreased in conditions that decrease the pressure in the left ventricle at end of diastole (hypovolemia)
PCWP is a reflection of the tendency to to develop pulmonary edema. To optimize cardiac performance and minimize tendency for pulmonary edema, the PCWP should be kept at the lowest point at which cardiac performance is acceptable 
PCWP
6-12
Cardiac Output (CO)
The amount of fluid and liters per minute that the heart pumps into systemic circulation. It is the product of: HR x SV
Seo is increased by factors that increase the heart rate or increase the amount of blood that the heart puts out with each beat (inotropic agents, excess fluid)
CO is decreased by factors that decrease the heart rate or decrease the amount of blood that the heart puts out with each beat (drugs that decrease contractility, Hypovolemia)
CO
4-8
Cardiac Index
The cardiac output/body surface area; more accurate measure than cardiac output because the value takes body surface area into account
CI
2.5-4
Systemic Vascular Resistance (SVR)
The resistance provided by the systemic circulation against which of the left ventricle must pump blood; calculated by the following formula:
(MAP-mean CVP X 80)/ CO
SVR
800-1200
Mixed Venous O2 Saturation (SVO2)
Continuous display of mixed Venus oxygen saturation by pulmonary artery catheter; assess the effectiveness of peripheral oxygen delivery
<60% = implies increase tissue extraction of O2; the patient has tapped the Venus reserve of O2; causes include decreased O2 supply (decree CEO, decreased FiO2, anemia) or increased O2 demand ( fever,shivering, increased work of breathing)
>80% = implies decrease tissue extraction of oxygen; high return him 02 is often a most early indicator of patient status changes; causes include increase O2 supply (FiO2 > need), decreased O2 demand (hypothermia), or decreased effective 02 delivery and uptake by the cells (sepsis, shift of the oxyhemoglobin curve to left)
