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2010 handbook of fluid, electrolyte and acid base imbalances 3rd


Handbook of

Fluid, Electrolyte, and
Acid-Base Imbalances
Third Edition
Joyce LeFever Kee, MS, RN
Associate Professor Emerita
College of Health Sciences
University of Delaware
Newark, Delaware

Betty J. Paulanka, EdD, RN
Dean and Professor
College of Health Sciences
University of Delaware
Newark, Delaware

Carolee Polek, RN, PhD
Associate Professor of Nursing
College of Health Sciences

University of Delaware
Newark, Delaware

Australia • Canada • Mexico • Singapore • Spain • United Kingdom • United States


Handbook of Fluid, Electrolyte, and
Acid-Base Imbalances:
Third Edition
Joyce LeFever Kee, Betty J. Paulanka,
Carolee Polek
Vice President, Career and Professional
Editorial: Dave Garza
Director of Learning Solutions:
Matthew Kane
Executive Editor: Steven Helba

© 2000, 2004, 2010 Delmar, Cengage Learning
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Publisher does not warrant or guarantee any of the products described herein or perform any independent analysis in
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Printed in the United States of America
1 2 3 4 5 XX 11 10 09


Dedication
To
Joyce Kee for her consistent
support to faculty development in
the School of Nursing in the
College of Health Sciences
at the University of Delaware.

iii


Contents

UNIT I



FLUIDS AND THEIR
INFLUENCE ON THE BODY / 1

Chapter 1: Extracellular Fluid Volume
Deficit (ECFVD) / 11
Chapter 2: Extracellular Fluid Volume
Excess (ECFVE) / 22
Chapter 3: Extracellular Fluid Volume Shift
(ECFVS) / 35
Chapter 4: Intracellular Fluid Volume
Excess (ICFVE) / 40

UNIT II

ELECTROLYTES AND THEIR
INFLUENCE ON THE BODY / 49

Chapter 5: Potassium Imbalances / 54
Chapter 6: Sodium and Chloride
Imbalances / 74

iv


Contents

● v

Chapter 7: Calcium Imbalances / 89
Chapter 8: Magnesium Imbalances / 105
Chapter 9: Phosphorus Imbalances / 116

UNIT III

ACID-BASE BALANCE AND
IMBALANCES / 127

Chapter 10: Determination of Acid-Base
Imbalances / 132
Chapter 11: Metabolic Acidosis and Metabolic
Alkalosis / 137
Chapter 12: Respiratory Acidosis and Respiratory
Alkalosis / 145

UNIT IV

INTRAVENOUS THERAPY / 153

Chapter 13: Intravenous Solutions and Their
Administration / 160
Chapter 14: Total Parenteral Nutrition (TPN) / 178

UNIT V

FLUID, ELECTROLYTE, AND ACID-BASE
IMBALANCES IN CLINICAL
SITUATIONS / 189

Chapter 15: Fluid Problems in Infants and
Children / 190
Chapter 16: Older Adults with Fluid and Electrolyte
Imbalances / 215


vi ●

Contents

Chapter 17: Acute Disorders: Trauma and Shock / 236
Chapter 18: Burns and Burn Shock / 263
Chapter 19: Gastrointestinal (GI) Surgical
Interventions / 275
Chapter 20: Neurotrauma: Increased Intracranial
Pressure / 285
Chapter 21: Clinical Oncology / 292
Chapter 22: Chronic Diseases with Fluid and Electrolyte
Imbalances: Heart Failure, Diabetic
Ketoacidosis, and Chronic Obstructive
Pulmonary Disease / 314
Appendix A: Common Laboratory Tests and
Values for Adults and Children / 354
Appendix B: Foods Rich in Potassium, Sodium,
Calcium, Magnesium, Chloride, and
Phosphorus / 375
Appendix C: The Joint Commission’s (TJC) List
of Accepted Abbreviations / 379
References/Bibliography / 383
Glossary / 393
Index / 404


Preface
The Handbook of Fluid, Electrolyte, and Acid-Base
Imbalances, Third Edition is developed from a parent text, Fluids and Electrolytes with Clinical Applications: A Programmed Approach, 8th Edition by
Joyce LeFever Kee, Betty J. Paulanka, and Carolee
Polek. It is designed to be used in the clinical setting, both in conjunction with the parent text and
as a stand-alone product. With a clear comprehensive approach, this quick reference pocket guide
of basic principles of fluid, electrolyte, and acidbase balances, imbalances, and related disorders
is a must-have for all who work in the field! The
convenient handbook size enables readers to keep
it handy for quick access to over 200 diagrams and
tables containing valuable information. A developmental approach is used to provide examples
across the life span that illustrate common health
problems associated with imbalances. The chapter on increased intracranial pressure has been
completely rewritten with a stronger focus on
neurotrauma and common conditions that cause
increased intracranial pressure. A glossary has
been added for quick reference. The reference/
bibliography list has been completely updated
and expanded. Also, the appendix on common lab
vii


viii ●

Preface

studies has been reduced to focus on lab studies with particular reference to fluid imbalances and electrolyte disorders
associated with the clinical manifestations of these disorders. A new appendix with the Joint Commission’s (TJC) list
of accepted abbreviations has been added for the reader’s
convenience. Nursing assessments, nursing diagnoses, interventions, and rationales are in a tabular format for quick
retrieval and ease of comprehension. All the important information readers need is right at their fingertips!

ORGANIZATION
Handbook of Fluid, Electrolyte, and Acid-Base Imbalances
comprises 22 chapters organized into five units:
Unit I lays the foundation for influence of fluids on the
body. It covers fluid imbalances related to extracellular fluid
volume deficit, excess, and fluid shift, and intracellular fluid
volume excess.
Unit II builds upon this material and discusses six electrolyte imbalances—potassium, sodium, chloride, calcium,
magnesium, and phosphorus.
Unit III provides a quick guide to determine the types of
acid-base imbalances.
Unit IV covers intravenous therapy. The chapters on intravenous fluid therapy and total parenteral nutrition (TPN)
include: calculation, monitoring IV fluids, and complications that may occur. With this strong foundation, the
learner can then move on to the more complex issues found
in the next unit.
Unit V focuses on Clinical Situations and outlines the
causes of fluid, electrolyte, and acid-base imbalances in a
brief reference style format. Chapters related to acute disorders (trauma and shock), burns and burn shock, gastrointestinal surgical interventions, increased intracranial pressure,
and chronic diseases such as heart failure, diabetic ketoacidosis, and chronic obstructive pulmonary disease are included.
Also addressed are the fluid problems of infants, children,
and older adults.


Preface

● ix

Glossary contains important definitions.
Appendix contains three appendices. These act as invaluable reference tools for the user. Included are common
laboratory tests and values for adults and children; a chart
listing foods rich in potassium, sodium, calcium, magnesium, chloride, and phosphorus; and a list of the Joint Commission’s (TJC) accepted abbreviations.

SYMBOLS
Throughout the handbook the following symbols are used: c
(increased), ↓ (decreased), Ͼ (greater than), Ͻ (less than). A
dagger (†) in tables indicates the most common signs and
symptoms.
The content in this book is geared for nurses (students,
licensed practitioners), laboratory personnel, technicians,
and all health care professionals wanting to learn more
about fluid, electrolyte, and acid-base imbalances that influence the health status of their patients.
Joyce L. Kee, RN, MS, Professor Emerita
Betty J. Paulanka, RN, EdD, Dean and Professor
Carolee Polek, RN, PhD,
Associate Professor of Nursing


Acknowledgments
We wish to extend our deepest appreciation to the
School of Nursing faculty: Ingrid Aboff, Shelia
Cushing, Judy Herrman, Kathy Schell, Gail Wade,
Erlinda Wheeler; a University of Delaware nursing
graduate, Linda Laskowski-Jones of Christiana
Care Health Systems for their contributions and
assistance.
We especially wish to thank Barbara Vogt, staff
assistant, for her valuable assistance and service
and for her coordination of correspondence.
We also offer our thanks to our editors Steven
Helba and Juliet Steiner at Delmar, Cengage Learning for their helpful suggestions and assistance.
Joyce LeFever Kee, RN, MS
Betty J. Paulanka, RN, EdD
Carolee Polek, RN, PhD

x


Contributors and
Consultants
Ingrid Aboff, RN, PhD
Assistant Professor, School of Nursing
College of Health Sciences
University of Delaware
Newark, Delaware
Shelia Cushing, RN, MS
Assistant Professor, School of Nursing
College of Health Sciences
University of Delaware
Newark, Delaware 19716
Judith Herrman, RN, PhD
Associate Professor, School of Nursing
College of Health Sciences
University of Delaware
Newark, Delaware 19716
Linda Laskowski-Jones, APRN, BC, CCRN CEN
Vice President Trauma,
Emergency Medicine and Aero Medical Services,
Christiana Care Health Systems
Wilmington, Delaware

xi


xii ●

Contributors and Consultants

Kathleen Schell, RN, DNSc
Associate Professor, School of Nursing
College of Health Sciences
University of Delaware
Newark, Delaware
Gail H. Wade, RN, DNSc
Associate Professor, School of Nursing
College of Health Sciences
University of Delaware
Newark, Delaware
Erlinda Wheeler, RN, DNSc
Associate Professor, School of Nursing
College of Health Sciences
University of Delaware
Newark, Delaware


Reviewers
Deb Aucoin-Ratcliff, RN, DNP
American River College
Sacramento, California
Vicki Bingham, PhD, RN
Chair of Academic Programs and Assistant
Professor of Nursing
School of Nursing
Delta State University
Cleveland, Mississippi
Doreen DeAngelis, MSN, RN
Nursing Instructor
Penn State Fayette, The Eberly Campus
Uniontown, Pennsylvania
Deborah J. Marshall, MSN, RN
Associate Professor, Nursing
Palm Beach Community College
Lake Worth, Florida
Deborah A. Raines, Ph.D., RN
Professor
Christine E. Lynn College of Nursing
Florida Atlantic University
Boca Raton, Florida

xiii


xiv ●

Reviewers

Barbara Scheirer RN, MSN
Assistant Professor
School of Nursing
Grambling State University
Grambling, Louisiana
Diann S. Slade, MSN, RN
Instructor
College of Pharmacy, Nursing, and
Allied Health Sciences
Howard University
Washington, D.C.


U
UN
NIITT

I

FLUIDS AND THEIR
INFLUENCE ON THE BODY
INTRODUCTION
The human body is a complex machine that contains
hundreds of bones and the most sophisticated interaction of systems of any structure on earth. Yet, the
substance that is basic to the very existence of the
body is the simplest substance known, WATER. In
fact, it makes up almost two-thirds of an adult’s
body weight.
Body water represents about 60% of the total
body weight in the average adult, 45–55% of an
older adult, 70–80% of a newborn infant, and 97%
of the early human embryo. Figure U1-1 demonstrates the percentage of body water concentration
across the life span. Many persons think the extra
water in infants acts as a protective mechanism.
Since infants have larger body surface in relation to
their weight, extra water acts as a cushion against
injury. Body fat is essentially free of water. An
obese person has less body water than a thin person. The leaner the individual, the greater the proportion of water in total body weight.

BODY COMPARTMENTS
Body water is distributed among three body compartments: intracellular (within the cells), intravascular
(within the blood vessels), and interstitial (within the
tissue spaces). Because fluids in the blood vessels
and tissue spaces are outside the cells, they are referred to as extracellular fluid. Table U1-1 gives the
proportion of intracellular and extracellular fluid in
the body.

1


2 ●

Unit I Fluids and Their Influence on the Body

Embryo

Newborn

Adult

Older adult

__________
97%

__________
70–80%

__________
60%

__________
45–55%

FIGURE U1-1 Percentages of body fluid per body weight.

Table U1-1

Percentage of Body Fluids in Body
Fluid Compartments
2

40%

1 13 2

20%

Intracellular fluid (ICF) compartment 1 3 2
Extracellular fluid (ECF) compartment
Interstitial fluid
Intravascular fluid
Total

15%
5%
____
60%

FUNCTIONS OF BODY WATER
Without water, the body is unable to maintain life. Five functions of water that the body needs to maintain a healthy
state are stated in Table U1-2.

Table U1-2






Functions of Body Water

Transportation of nutrients, electrolytes, and oxygen to the cells
Excretion of waste products
Regulation of body temperature
Lubrication of joints and membranes
Medium for food digestion


Unit I Fluids and Their Influence on the Body

Table U1-3

● 3

Daily Body Fluid Intake
and Losses

Fluid Intake

Fluid Losses

Liquid
Food
Oxidation

1000–1200 mL
800–1000 mL
200–300 mL

Total

2000–2500 mL

Urine
Feces
Lungs
Skin

1000–1500 mL
100 mL
400–500 mL
300–500 mL
1800–2600 mL

When body water is insufficient and the kidneys are functioning normally, urine volume diminishes and the individual
becomes thirsty. Therefore, the person drinks more water to
correct the fluid deficit. When there is an excessive amount
of water intake, the urine output increases proportionately.
Sources of fluid intake include liquids, foods, and products of the oxidation of food process. The average intake
and output of fluid per day is 1800–2600 mL. Body fluids
are lost daily through the urine, feces, lungs, and skin.
Body water loss through the skin, which is not measurable,
is called insensible perspiration. Appropriately 300–500 mL
of fluid is lost daily through processes such as sweat gland
activity. Table U1-3 lists the daily body fluid intake and
losses. Definitions related to fluid functions and movement
are presented in the accompanying box.

Definitions Related to Fluid Function and Movement
Membrane. A layer of tissue covering a surface or organ
or separating spaces.
Permeability. The capability of a substance, molecule,
or ion to diffuse through a membrane.
Semipermeable membrane. An artificial membrane
such as a cellophane membrane.
Selectively permeable membrane. Permeability of the
human membranes.
Solvent. A liquid with a substance in solution.
Solute. A substance dissolved in a solution.
Osmosis. The passage of a solvent through a membrane from a solution of lesser solute concentration to
one of greater solute concentration.


4 ●

Unit I Fluids and Their Influence on the Body

Note: Osmosis may be expressed in terms of water
concentration instead of solute concentration.
Water molecules pass from an area of higher
water concentration (fewer solutes) to an area
of lower water concentration (more solutes).
Diffusion. The movement of molecules such as gas
from an area of higher concentration to an area of
lesser concentration. Large molecules move less
rapidly than small molecules.
Osmol. A unit of osmotic pressure. The osmotic effects
are expressed in terms of osmolality. A milliosmol
(mOsm) is 1/1000th of an osmol and determines the
osmotic activity.
Osmolality. Osmotic pull exerted by all particles per
unit of water, expressed as osmols or milliosmols per
kilogram of water concentrate and body fluids.
Osmolarity. Osmotic pull exerted by all particles per
unit of solution, expressed as osmols or milliosmols
per liter of solution.
Ion. A particle carrying a positive or negative charge.
Plasma. Blood minus the blood cells (composed mainly
of water).
Serum. Plasma minus fibrogen (obtained after coagulation
of blood).
Tonicity. The effect of fluid on cellular volume
concentration of IV solutions.

FLUID PRESSURES (STARLING’S LAW)
Extracellular fluid (ECF) shifts between the intravascular
space (blood vessels) and the interstitial space (tissues) to
maintain a fluid balance within the ECF compartment. There
are four measurable pressures that determine the flow of
fluid between the intravascular and interstitial spaces. These
are the colloid osmotic (oncotic) pressures and the hydrostatic pressures that occur in both the vessels and the tissue
spaces. The colloid osmotic pressure and the hydrostatic
pressure of the blood and tissues influence the movement of
fluid through the capillary membrane. Fluid exchange occurs
only across the walls of capillaries and not across the walls
of arterioles or venules. Therefore, fluid moves into the interstitial space at the arteriolar end of the capillary and out of
the interstitial space into the capillary at the venular end of
the capillary.


Unit I Fluids and Their Influence on the Body

● 5

Intravascular Fluid
Plasma hydrostatic pressure (18 mm Hg)
Plasma colloid osmotic pressure (28 mm Hg)
Capillary

Tissue space

Interstitial Fluid
Tissue hydrostatic pressure (– 6 mm Hg)
Tissue colloid osmotic pressure (4 mm Hg)
Arteriole End:
Movement of fluid is from
blood stream into tissue space

Venous End:
Movement of fluid is from
tissue space into blood stream

FIGURE U1-2 Pressures in the intravascular and interstitial fluid.

Fluid flows only when there is a difference in pressure at
the two ends of the system. The difference in pressure
between two points is known as the pressure gradient. If
the pressure at one end is 32 mm Hg and at the other end is
26 mm Hg, the pressure gradient is 6 mm Hg. The plasma in
the capillaries has hydrostatic pressure and colloid osmotic
pressure. The tissue fluids have hydrostatic pressure and
colloid osmotic pressure. The difference in pressure between
the plasma colloid osmotic pressure and the tissue colloid osmotic pressure is known as the colloid osmotic pressure gradient; likewise, the difference in pressure between the plasma
hydrostatic pressure and the tissue hydrostatic pressure is
known as the hydrostatic pressure gradient. Figure U1-2 describes the fluid flow based upon the pressures in the intravascular and interstitial spaces.
Because the plasma hydrostatic pressure (18 mm Hg) in
the arteriolar end of the capillary is higher than the tissue
hydrostatic pressure (Ϫ6 mm Hg) in the tissue spaces, fluid
moves out of the capillary and into the tissue spaces. The
plasma colloid osmotic pressure (28 mm Hg) in the venular
end of the capillary is higher than the tissue colloid osmotic
pressure (4 mm Hg) in the tissue spaces, causing fluids to


6 ●

Unit I Fluids and Their Influence on the Body

move from the tissue spaces into the capillary. Without the
colloid osmotic forces, fluid is lost from circulation and remains in the tissues, causing swelling or edema.

REGULATORS OF FLUID BALANCE
Thirst, electrolytes, protein and albumin, hormones, enzymes, lymphatics, skin, and kidneys are major regulators
that maintain body fluid balance. Thirst alerts the person
that there is a fluid loss; thus, thirst stimulates the person to
increase his or her oral intake. The thirst mechanism in the
medulla may not respond effectively to a fluid deficit in the
older adult or the very young child; therefore, these groups
of individuals are prone to lose fluid and become easily dehydrated. Table U1-4 lists the various regulators of fluid balance and indications of how the body compensates for fluid
changes.
If a person is febrile or there is an increase in humidity,
diaphoresis may occur. This causes a fluid loss. The amount
of fluid loss from the skin in this situation may be greater
than 500 mL for the day. Deep and rapid breathing or hyperventilation can also increase fluid loss through the lungs in
an amount greater than 500 mL.

Table U1-4

Regulators of Fluid Balance

Regulators

Actions

Thirst

An indicator of fluid need.

Electrolytes
and Non-electrolytes
Sodium

Protein, albumin

Sodium promotes water retention. With a
water deficit, less sodium is excreted
via kidneys; thus, more water is
retained.
Protein and albumin promote body fluid
retention. These non-diffusible
substances increase the colloid osmotic
(oncotic) pressure in favor of fluid
retention.
(continues)


Unit I Fluids and Their Influence on the Body

Table U1-4

Regulators of Fluid Balance—
continued

Hormones and Enzymes
Antidiuretic hormone (ADH)

Aldosterone

Renin

Body Tissues and Organs
Lymphatics

Skin

Lungs

Kidneys

● 7

ADH is produced by the hypothalamus and stored in the posterior
pituitary gland (neurohypophysis).
ADH is secreted when there is an
ECF volume deficit or an increased
osmolality (increased solutes). ADH
promotes water reabsorption from
the distal tubules of the kidneys.
Aldosterone is secreted from the
adrenal cortex. It promotes sodium,
chloride, and water reabsorption
from the renal tubules.
Decreased renal blood flow increases
the release of renin, an enzyme,
from the juxtaglomerular cells of
the kidneys. Renin promotes
peripheral vasoconstriction and the
release of aldosterone (sodium and
water retention).
Plasma protein that shifts to the
tissue spaces cannot be
reabsorbed into the blood
vessels. Thus, the lymphatic
system promotes the return of
water and protein from the
interstitial spaces to the vascular
spaces.
Skin excretes approximately
300–500 mL of water daily
through normal perspiration.
Lungs excrete approximately
400–500 mL of water daily
through normal breathing.
The kidneys excrete 1000–1500 mL
of body water daily. The amount
of water excretion may vary
according to the balance between
fluid intake and fluid loss.


8 ●

Unit I Fluids and Their Influence on the Body

OSMOLALITY
Osmolality (serum) is determined by the number of dissolved
particles, mainly sodium, urea, and glucose, per kilogram of
water. Sodium is the largest contributor of particles to osmolality. The normal serum osmolality range is 280–295 mOsm/kg
(milliosmols per kilogram); serum osmolality values in this
range are considered iso-osmolar since the serum concentration is similar to plasma. If the serum osmolality is less
than (Ͻ) 280 mOsm/kg, the serum concentration of fluid is
hypo-osmolar, and if the serum osmolality is greater than (Ͼ)
295 mOsm/kg, the serum concentration is hyperosmolar. The
serum osmolality is “roughly” estimated by doubling the
serum sodium level. For example, if the serum sodium is 142
mEq/L, the serum osmolality is 284 mOsm/kg. Doubling the
serum sodium level provides a “rough estimate” of the serum
osmolality.
The terms osmolality and tonicity have been used interchangeably; though similar, they are different. Osmolality is
the concentration of body fluids and tonicity is the concentration of IV solutions. Increased osmolality (hyperosmolality) can
result from permeable solutes such as sodium and permeant
solutes such as urea (blood urea nitrogen). Hyperosmolality
results from an increase of impermeant solutes such as
sodium, but not of permeant solutes such as urea (BUN). Hyperosmolality of body fluid occurs with an increased serum
sodium and BUN levels; however, it may also cause isotonicity
since the BUN does not affect tonicity. Serum osmolality is a
better indicator of the concentration of solutes in body fluids
than tonicity measures. Tonicity is primarily used for the concentration of intavenous solutions.

TONICITY OF INTRAVENOUS (IV) SOLUTION
The tonicity of an IV solution can be hypo-osmolar or hypotonic, iso-osmolar or isotonic, hyperosmolar or hypertonic. The
tonicity of an IV solution is determined by the serum osmolality average, which is 290 mOsm/kg (280–295 mOsm/kg). The
normal range for the tonicity of a solution is ϩ50 mOsm
or Ϫ50 mOsm of 290 mOsm, or 240–340 mOsm. Tonicity may
be used to describe the concentration of IV solution because
of the effect of permeable solutes like sodium and chloride in


Unit I Fluids and Their Influence on the Body

● 9

the solution on the cellular volume. The concentration of IV
solutions is referred to as hypotonic, isotonic, or hypertonic.
A liter of 5% dextrose in water (D5W) is 250 mOsm, and a
liter of 0.9% sodium chloride or normal saline is 310 mOsm;
both solutions have somewhat the same tonicity as plasma.
These solutions are isotonic. However, in D5W, the dextrose
is metabolized quickly, causing the solution to become hypotonic. The tonicity of a liter of 5% dextrose in water with 0.9%
sodium chloride is 560 mOsm. This solution is hypertonic.
Many disease entities have some degree of fluid imbalance
such as fluid loss, fluid excess, and/or fluid volume shift. The
four major fluid imbalances: extracellular fluid volume deficit
(ECFVD), extracellular fluid volume excess (ECFVE), extracellular fluid volume shift (ECFVS), and intracellular fluid volume
excess (ICFVE) are discussed in Chapters 1, 2, 3, and 4.

CLINICAL PROBLEMS ASSOCIATED WITH
FLUID IMBALANCES
Table U1-5 illustrates the most common clinical problems
associated with fluid imbalances.

Table U1-5
Clinical Problems
Gastrointestinal
Vomiting and diarrhea
Gl fistula
Gl suctioning
Increased salt intake
Intestinal obstruction
Perforated ulcer
Excessive hypotonic fluids,
oral and intravenous
Renal
Renal failure
Renal disease
Cardiac
Heart failure

ECFVD

ECFVE ECFV Shift

ϩ
ϩ
ϩ
ϩ
ϩ
ϩ

ICFVE

ϩ
ϩ
ϩ
ϩ
ϩ
ϩ
(continues)


10 ●

Unit I Fluids and Their Influence on the Body

Table U1-5

continued

Clinical Problems
Miscellaneous
Brain tumor/injury
Fever
Profuse diaphoresis
SIADH (syndrome of
inappropriate antidiuretic
hormone)
Burns
Diabetic ketoacidosis
Ascites
Venous obstruction
Sprain
Massive trauma
Drugs
Cortisone group of drugs

ECFVD

ECFVE

ECFV Shift

ICFVE

ϩ
ϩ
ϩ
Initially
ϩ
ϩ
ϩ

ϩ

ϩ

ϩ

ϩ
ϩ

ϩ
ϩ
ϩ

ϩ
ϩ


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