51
Circulation
Learning Outcomes
1. Outline the structure and function of the
cardiovascular system.
2. Identify major risk factors for the
development of cardiovascular disease and
related health promotion objectives from
Healthy People 2020.
3. Describe three major alterations in
cardiovascular function.
4. Outline the nursing management of a client
with cardiovascular disease.
continued on next slide
Learning Outcomes
5. Describe the critical nature of
cardiopulmonary resuscitation.
6. Verbalize the steps used in:
a. Applying a sequential compression device.
7. Recognize when it is appropriate to delegate
aspects of applying a sequential compression
device to unlicensed assistive personnel.
8. Demonstrate appropriate documentation and
reporting when applying a sequential
compression device.
Physiology of the Cardiovascular
System
• Respiratory and circulatory systems
linked
• Function of one affects the other.
The Heart
• Enclosed by pericardium
• Layers are epicardium, myocardium,
endocardium.
• Chambers are two upper atria, two
lower ventricles separated by septum.
• Atrioventricular (AV) valves separate
atria from ventricles.
▪ Tricuspid (right)
▪ Bicuspid or mitral (left)
The Heart
• Semilunar (half-moon) valves separate
ventricles from great vessels.
• Deoxygenated blood enters right side of
heart, exits to lungs.
• Oxygenated blood returns via left side
of heart, exits to body.
Figure 51–1 The layers of the heart: the epicardium, the myocardium, and the endocardium.
From Medical Terminology: A Word-Building Approach, 7th ed. (p. 263), by J. Rice, 2012. Reproduced by
permission of Pearson Education, Inc., Upper Saddle River, New Jersey.
Figure 51–2 Heart valves in closed position viewed from the top.
From Medical Terminology: A Word-Building Approach, 7th ed. (p. 266), by J. Rice, 2012. Reproduced by
permission of Pearson Education, Inc., Upper Saddle River, New Jersey.
The Heart
• Coronary circulation
▪ Coronary arteries
• Atherosclerotic plaque or clot
• Angina or myocardial infarction (heart
attack)
• Cardiac cycle
▪ Systole (propels blood)
▪ Diastole (ventricular filling)
▪ Heart sounds
Figure 51–3 The functioning of the heart valves and blood flow through the heart.
From Medical Terminology: A Word-Building Approach, 7th ed. (p. 264), by J. Rice, 2012. Reproduced by
permission of Pearson Education, Inc., Upper Saddle River, New Jersey.
The Heart
• Cardiac conduction system
▪ Automaticity
▪ Sinoatrial (SA or sinus) node
▪ Atrioventricular (AV) node
▪ Bundle of His
▪ Purkinje fibers
The Heart
• Cardiac output (CO)
▪ Amount of blood ejected from the heart
each minute
▪ Stroke volume (SV)
• Amount of blood ejected from the heart
with each beat
continued on next slide
The Heart
• Cardiac output (CO)
▪ SV × HR = CO
• Normal CO is 4 to 8 L/min.
▪ Heart rate
• Number of beats per minute
• If HR is more than 150/min, ventricles
cannot refill and CO will fall.
continued on next slide
The Heart
• Cardiac output (CO)
▪ Preload
• Degree of stretch of ventricles at end of
diastole
• Depends largely on blood return from
veins
• Increased volume leads to more forceful
contraction of heart (Frank-Starling law)
continued on next slide
The Heart
• Cardiac output (CO)
▪ Contractility
• Inotropic state of the myocardium,
strength of contraction
• Autonomic nervous system and inotropic
medications affect it.
continued on next slide
The Heart
• Cardiac output (CO)
▪ Afterload
• Pressure within arteries that ventricles
must overcome to push blood into
circulation
• Left ventricle must work harder than
right.
Anatomy and Physiology Review Preload and
Afterload
Blood Vessels
• Low-pressure pulmonary system
• Higher-pressure systemic system
• Arteries generally carry oxygenated
blood and veins carry deoxygenated
blood.
▪ Opposite in pulmonary system
• Most blood vessels have tunica intima,
tunica media, and tunica adventitia.
Blood Vessels
• Arterial circulation
▪ Blood pressure (BP)
• Peripheral vascular resistance (PVR) ×
CO = mean arterial pressure (MAP)
• PVR determined by:
• Viscosity (thickness) of blood
• Blood vessel length
• Blood vessel diameter
Blood Vessels
• Venous return
▪ Respiratory pump
▪ Muscular pump
▪ Venous valves
Blood
• Functions
▪ Transporting oxygen, nutrients, and
hormones to cells and removing waste
▪ Regulating body temperature, pH, and
fluid volume
▪ Preventing infection and blood loss
• Hemoglobin
▪ Major component of RBC
▪ Binds easily with oxygen
Figure 51–6 The heart and blood vessels. The left side of the heart pumps oxygenated blood into the arteries.
Deoxygenated blood returns via the venous system into the right side of the heart.
Lifespan Considerations
• Birth
▪ Profound change from fetal to newborn
circulation
▪ Pulse rates highest and most varied in
newborns
• 100–180 bpm at birth
• Later 100–150 bpm
▪ BP 65/40 first few days, 90/55 by 1
month
Lifespan Considerations
• 2 years
▪ 80–120 bpm
• 10 years to adult
▪ 60–95 bpm
▪ BP gradually rises to about 110/65 by
16 years.
• May rise in later years with
atherosclerosis
Factors Affecting Cardiovascular
Function
• Risk factors
▪ Nonmodifiable risk factors
• Heredity
• Age
• Gender
continued on next slide
Factors Affecting Cardiovascular
Function
• Risk factors
▪ Modifiable risk factors
• Elevated serum lipid levels
• Hypertension
• High sodium intake
• Cigarette smoking
• Diabetes
• Obesity
• Sedentary lifestyle
continued on next slide
Factors Affecting Cardiovascular
Function
• Risk factors
▪ Nontraditional risk factors
• Metabolic syndrome
• C-reactive protein
• Elevated homocysteine level
Alterations in Cardiovascular
Function
• Conditions affect:
▪ Functioning of the heart as a pump
▪ Blood flow to organs and peripheral
tissues
▪ Composition of blood and its ability to
transport oxygen and carbon dioxide
Alterations in Cardiovascular
Function
• Decreased cardiac output
▪ Myocardial infarction
• Chest pain
• Substernal and/or radiating to left arm or
jaw
• Nausea
• Shortness of breath
• Diaphoresis
continued on next slide
Alterations in Cardiovascular
Function
• Decreased cardiac output
▪ Heart failure
• Can develop if heart not able to keep up
with body's need for oxygen and
nutrients
• Usually occurs because of MI
• May result from chronic overwork of
heart
• Left-sided heart failure can result in
pulmonary edema.
continued on next slide
Alterations in Cardiovascular
Function
• Decreased cardiac output
▪ Heart failure
• Signs
• Pulmonary congestion
• Adventitious breath sounds
• Shortness of breath
• Dyspnea on exertion
• Increased HR
continued on next slide
Alterations in Cardiovascular
Function
• Decreased cardiac output
▪ Heart failure
• Signs
• S3 heart sound
• Increased RR
• Nocturia
• Othopnea
• Distended neck veins
▪ Structural defects or infections
Box 51–2 Examples of Conditions That May
Precipitate Heart Failure
Alterations in Cardiovascular
Function
• Impaired tissue perfusion
▪ Ischemia
• Impaired blood flow due to obstruction
▪ Atherosclerosis
• Most common cause of impaired blood
flow to organs and tissues
• Vessels narrow and become constricted.
• Distal tissues receive less oxygen and
nutrients.
continued on next slide
Alterations in Cardiovascular
Function
• Impaired tissue perfusion
▪ Atherosclerosis
• Coronary arteries most affected
• Obstruction leads to myocardial ischemia
and may lead to angina pectoris or
myocardial infarctions (MI).
• Obstruction in vessels supplying brain
results in TIA or stroke.
continued on next slide
Alterations in Cardiovascular
Function
• Impaired tissue perfusion
▪ Atherosclerosis
• Obstruction in peripheral arteries leads to
peripheral vascular disease and possible
gangrene.
• Signs include pulses, pain, paresthesias,
pallor, coolness, and decreased hair
distribution.
continued on next slide
Alterations in Cardiovascular
Function
• Impaired tissue perfusion
▪ Vessel inflammation
▪ Arterial spasms
▪ Blood clots
▪ Incompetent venous valves
▪ May allow blood to pool in veins
• Edema
• Decreased venous return to heart
continued on next slide
Alterations in Cardiovascular
Function
• Impaired tissue perfusion
▪ Incompetent venous valves
▪ Veins become inflamed.
• Reduce blood flow
• Increased risk of thrombus formation
▪ Thrombi may break loose.
• Emboli
• Occlude blood supply at alveolar–
capillary membrane
continued on next slide
Alterations in Cardiovascular
Function
• Impaired tissue perfusion
▪ Acute pulmonary embolism
• Sudden onset of shortness of breath
• Pleuritic chest pain
• Medical emergency
Figure 51–7 Left: Vein with competent valve; right, vein with incompetent valve that allows blood to pool in
the veins.
From Medical Terminology: A Word-Building Approach, 7th ed. (p. 298), by J. Rice, 2012. Reproduced by
permission of Pearson Education, Inc., Upper Saddle River, New Jersey.
Alterations in Cardiovascular
Function
• Blood alterations
▪ Anemia
• Chronic fatigue
• Pallor
• Shortness of breath
• Hypotension
continued on next slide
Alterations in Cardiovascular
Function
• Blood alterations
▪ Blood volume
• Hemorrhage
• Severe dehydration
• Hypervolemia
▪ Sickle cell disease
Assessing
• Nursing history
▪ Current, past cardiovascular problems
▪ Family history
• Physical assessment
▪ BP
▪ Lung sounds
▪ Skin
▪ Ankle brachial index (ABI)
Assessing
• Diagnostic studies
▪ Cardiac monitoring
▪ Blood tests
• Hemoglobin
• Electrolytes
• Creatinine kinase (CK)
• Troponin
Figure 51–8 A client with cardiac monitoring.
Assessing
• Diagnostic studies
▪ Hemodynamic studies
• Continuous monitoring for clients with
known or suspected CVD
• During and after surgery
• Monitor responses to drug therapy
• At risk for serious complications such as
shock
Diagnosing
• Decreased Cardiac Output
• Risk for Peripheral Neurovascular
Dysfunction
• Activity Intolerance
Planning
• Maintain or improve tissue perfusion
• Maintain or restore adequate cardiac
output
Implementing
• Promoting circulation
▪ Vascular function
• Elevate client's legs
• Avoid placing pillows under knees or
providing more than 15° knee flexion
• Encourage leg exercises for client on bed
rest
• Promote ambulation as soon as possible
• Encourage or provide frequent position
changes
continued on next slide
Implementing
• Promoting circulation
▪ Cardiac function
• Position client in high Fowler's position
• Monitor intake and output
• Maintain fluid restriction as ordered
continued on next slide
Implementing
• Promoting circulation
▪ Help client understand purposes,
effects, and side effects
▪ Assess effects of medications and
potential complications
▪ Assess intake and output and potassium
levels, if appropriate, for clients
receiving diuretics
continued on next slide
Implementing
• Promoting circulation
▪ Assess BP, HR, peripheral pulses, and
lung sounds for clients receiving positive
inotropic medications
▪ Monitor BP (including postural blood
pressure) for clients receiving
antihypertensive medications
Implementing
• Medications
▪ Nitrates, calcium channel blockers, and
ACE inhibitors
▪ Positive inotropic drugs
▪ Beta-adrenergic blocking agents
▪ Direct vasodilators
▪ Many clients on multiple medications
▪ Assess for effects and potential
complications
Implementing
• Preventing venous stasis
▪ Positioning and leg exercises
▪ Applying antiemboli stockings
▪ Applying sequential compression
devices (SCDs)
Figure 51–9 Sequential venous compression devices enhance venous return. They are available in knee-high
or thigh-length versions.
Skill 51–1 Sequential Compression Devices
continued on next slide
Skill 51–1 (continued) Sequential Compression
Devices
continued on next slide
Skill 51–1 (continued) Sequential Compression
Devices
continued on next slide
Skill 51–1 (continued) Sequential Compression
Devices
Implementing
• Cardiopulmonary resuscitation
▪ CPR
• Oral resuscitation and cardiac massage
to reestablish cardiac function and blood
circulation after cardiac arrest
• Within 20 to 40 seconds of a cardiac
arrest, victim is clinically dead.
continued on next slide
Implementing
• Cardiopulmonary resuscitation
▪ CPR
• After 4 to 6 minutes, lack of oxygen to
the brain causes permanent, extensive
damage.
• Must initiate immediately
Implementing
• Cardiopulmonary resuscitation
▪ Three cardinal signs of cardiac arrest
• Apnea
• Absence of a carotid or femoral pulse
• Dilated pupils
▪ Respiratory (pulmonary) arrest
• Usually from blocked airway or cardiac
arrest
Implementing
• Cardiopulmonary resuscitation
▪ Calling a code
▪ Therapeutic presence is a key nursing
intervention.
Evaluating
• Collect data to evaluate effectiveness of
interventions
• If desired outcomes are not achieved,
the nurse, client, and support person
need to explore reasons before
modifying the care plan.
▪ Are other outcomes met?
Evaluating
• If desired outcomes are not achieved,
the nurse, client, and support person
need to explore reasons before
modifying the care plan.
▪ Are there additional stressors?
• Signs of fluid overload?
▪ Are medications being taken?
