NR 340 Exam2 Study guide (Version 2), Chamberlain College of Nursing

NR340 Exam 2 Ch: 4, 8, 11, 19 Page 1 of 27




NR 340 Exam 2

Hemodynamics
 Studies relationships among several variables:
o Heart rate
o Blood flow
o Oxygen delivery
o Tissue perfusion
 A&P Cardiovascular System
o Pumps oxygenated blood via arteries to systemic circulation
o Receives deoxygenated blood via venous vasculature
 Cardiac Output
o Cardiac output—volume of blood ejected from heart/min
o CO = HR × Stroke volume (volume of blood ejected with each beat)
 Normal: 4 to 8 L/min
 Ejection fraction—fraction of blood ejected with each beat
o Normal: 60% to 70%
o Can be determined from echocardiogram
 Preload
o Degree of muscle fibers stretch before systole
 Volume of blood in ventricle prior to contraction (LVEDV/LVEDP)
o Measurements
 CVP (Central Venous Pressure)/ RAP (Right Atrial Pressure)
 Measures right-sided preload
 PAP (Pulmonary Artery Pressure) /PAOP (Pulmonary AtertyOcculsion Pressure)
 Measures left sided preload
 If measurements are ↑ means Preload ↑
 If ↓ means Preload is ↓
o INCREASED Preload
 Causes:
 Left Ventricular Dysfunction
 Right Ventricular Dysfunction
 HYPERvolemia
 Clinical Manifestations:
 Jugular Vein Distension
 Generalized Edema
 Crackles
 Pulmonary Edema (Pink Frothy Sputum)
 Ascites

,NR340 Exam 2 Ch: 4, 8, 11, 19 Page 2 of 27

 Treatments:
 Diuretics
 ↑ HOB
o DECREASED Preload
 Causes:
 HYPOvolemia
 Clinical Manifestations:
 Dry Mucous Membranes, Tenting Skin Turgor
 Treatments:
 ↓ Fluid Loss
 Administer Fluids
 Afterload
o Pressure or resistance against flow
o Related to lumen size and viscosity
 Systemic vascular resistance
 Force blood needs to overcome by the left ventricle upon contraction
 Pulmonary vascular resistance
 Force blood needs to overcome by the right ventricle upon contraction
o Measurements
 PVR- Right sided afterload
 SVR- left sided afterload
o INCREASED Afterload
 Causes:
 Vasoconstriction
 Pulmonary HTN (Right Sided)
 Systemic HTN (Left Sided)
 Clinical Manifestations:
 Capillary Refill >3 seconds
 Cool Extremities
 Treatments:
 ACE Inhibitors
 Vasodilators
o DECREASED Afterload
 Causes:
 Vasodilation
 Clinical Manifestations:
 Flushed Skin
 Warm Skin
 Treatments:
 Vasopressors
 Contractility
o Force of ventricular contraction
o How well the heart is pumping
o Preload and Afterload Effect Contractility
o INCREASED Contractility

, NR340 Exam 2 Ch: 4, 8, 11, 19 Page 3 of 27

 Causes:
 Stimulants
 ↑SNS Response
 Clinical Manifestations:
 Bounding Pulses (+4)
 Treatment:
 Only treat if causing adverse effects ie. Chest Pain
 Betablockers
o DECREASED Contractility
 Causes:
 Heart Failure
 ↑K+
 ↓ Ejection Fraction
 Acidosis
 Clinical Manifestations:
 Weak/Thready Pulses (+1)
 Treatments:
 Correct Acidosis
 Ventricular Assistive Devices
 Fix K+
 Insulin and D50
 Calcium Gluconate (Does not fix K+ but protects heart from effects of ↑K+)
 +Inotropic Drugs
 Dobutamine
 Digoxin
 Systemic Vascular Resistance (SVR)
o Peripheral vascular resistance
 Diameter of blood vessels
o Arterial BP = CO × SVR
 ↓ BP is great indicator of ↓ CO
 Cause needs to be determined
 Blood Pressure
o MAP= (Systolic BP + (2*Diastolic BP))/3
 Normal: 70 - 100
 Cardiac Output Versus Cardiac Index (CI)
o Index is a better assessment; based on body size
o CI = CO ÷ body surface area
 Calculated on the computer after entering patient’s height and weight
o Normal: 2.5 – 4.5
 Hemodynamic Monitoring
o Noninvasive modalities
 Noninvasive blood pressure
 Assessment of jugular venous pressure
 JVD = ↑ Preload
 Assessment of serum lactate levels (From Arterial Blood) or Lactic Acid Levels (Venous Blood)