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A PROTOCOL FOR THE INTERPRETATION OF FOUR
COMMONLY ORDERED LABORATORY VALUES
IN OLDER ADULTS

Scholarly Project for the Degree of M‘ S‘
MICHIGAN STATE UNIVERSITY
CHARLOTTE WAGENHEIM
1996

 

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A Protocol for the Interpretation of Four Commonly Ordered
Laboratory Values in Older Adults

by

Charlotte Wagenheim

A Scholarly Project

Submitted to
Michigan State University
College of Nursing
in partial fulfillment of the requirements
for the degree of

Master of Science

College of Nursing

1 996

ABSTRACT

A Protocol for the Interpretation of Four Commonly Ordered
Laboratory Values in Older Adults

by

Charlotte Wagenheim

Diagnostic testing enables the Advanced Practice Nurse to
identify pathological conditions and alterations in health status in elderly
patients and, then, plan appropriate interventions.

Current standards are based on laboratory results of younger adults and
do not take into account factors such as diet, drugs, exercise or normal
changes of aging which are significant for the elderly population.

The purpose of this project was to develop a protocol for assessment of
four commonly ordered laboratory values: Erythrocyte Sedimentation Rate
(ESR), Serum Glucose, Total Cholesterol and Serum Magnesium along with
adjusted reference ranges for geriatric patients and a description of the
laboratory tests, reasons for ordering the tests, interpretation of the results for
each test, adult reference ranges and reference ranges for adults > 65 years

old.

ACKNOWLEDGMENTS

To the members of my committee, Sharon King , Kate Lein and
Jackie Wright thank you for your committment to the project. You have
facilitated the process and your encouragement and expertise are much
appreciated.

To my husband, George, this goal has been reached because of your
love and faith in me. I could not have done it without you. And, to
Jacki Ann and Christopher, your support and cooperation have made this

project an accomplishment for all of us. Thank you.

TABLE OF CONTENTS
Introduction ............................................................................................ I
Purpose of the Study ................................................................................ 3
Literature Review ..................................................................................... 4
Erythrocyte Sedimentation Rate ..................................................... 7
Serum Glucose .............................................................................. 8
Total Cholesterol ........................................................................... 12
Serum Magnesium ........................................................................ l6
Conceptual Framework ........................................................................... l9
Fourteen Components .................................................................... 20
Nursing Process ............................................................................. 24
Development of the Project ...................................................................... 27
Purpose .......................................................................................... 27
Procedure ....................................................................................... 29
Evaluation of the Protocol .............................................................. 31
Implications for the Future ............................................................. 32
Research ........................................................................................ 33
Summary ....................................................................................... 34
References ............................................................................................... 36

Appendices .......................................................................................... 41-42

A Protocol For The Interpretation Of Four Commonly Ordered Laboratory

Values In Older Adults

Introduction

It is known that the United States is becoming an aging society.
Elderly are increasing in numbers and census figures indicate that there were
nearly 34 million Americans over the age of 65 in 1995. AdditiOnally, those
over the age of 85 are the fastest growing age group at present and this trend
will continue into the next century (Older Women’s League, 1995). Office
visits to primary health care practitioners by aged persons are increasing
correspondingly. Over 208 million office visits took place in 1989. The
number of visits to general surgeons in the same year was estimated at 23.8
million, with 7.2 million in the 65-75 and older age-range (U.S.D.H.H.S.,

1993).

Factors such as multi-drug regimens, nutrition and exercise need to be
acknowledged in order to meet the needs of geriatric patients. Accuracy of

test results leads to more accurate diagnoses, increased patient satisfaction, a

potential decrease in the number of office visits and, in the long run, a
decrease in overall healthcare costs.

The use of laboratory testing in primary care is a part of the
practitioner’s professional responsibility to the patient. Diagnostic testing
enables the practitioner to identify pathological conditions or altered health
states as part of the assessment process and is routinely ordered as part of a
total health screening. Duthie (1991) states, “Efficient use of laboratory
testing is essential in the care of the elderly, both for making accurate
diagnoses and keeping costs in line.” Standards have been established for
laboratory tests in order to interpret findings and make comparisons with the
general population, however, it is important to note that in the elderly, many
values change with age and an abnormal value might not be indicative of
disease (Wolf-Klein, 1989).

The role of the Advanced Practice Nurse (APN) is clear. Within the
primary care setting the APN must correctly identify abnormal laboratory
values in elderly patients in order to accurately diagnose problems and then
identify and initiate appropriate interventions. Too often patients’ signs and

symptoms are perceived as expected changes of aging and the same holds

true for abnormal laboratory findings. Lack of knowledge in this area leads
to under- or over-diagnosing of major health problems (Melillo, 1993).
Purpose of the Study

The purpose of this study is to formulate a protocol for healthcare
providers to enhance accurate interpretation of laboratory test results for
elderly patients. This protocol may be utilized in private practices, clinics,
nursing homes and other primary care settings by all healthcare providers
with specific focus on the APN.

The proposed protocol will outline appropriate reference ranges for
geriatric patients for the following laboratory values: Erythrocyte
Sedimentation Rate (ESR), Serum Glucose, Total Cholesterol, and Serum
Magnesium. These are four frequently ordered laboratory tests which could
easily be misinterpreted by practitioners in primary care and which could
have significant implications to the treatment of elderly patients. Reference
ranges refer to 95% distribution of values of a laboratory test with (+) or (-)
two standard deviations.

Four laboratory tests which were previously identified by the author as
potentially falling outside of the commonly accepted norms for elderly

patients include Erythrocyte Sedimentation Rate, Serum Glucose, Total

Cholesterol, and Serum Magnesium. These four tests are routinely ordered
for elderly patients by advanced practice nurses and are used to determine
potential health problems such as, diabetes, hyperlipidemia, gout, and hypo-
or hypermagnesemia (Mosby, 1995). Studies have shown, however, that
these particular tests are sometimes misinterpreted and may vary in what is

“normal” for elderly patients, especially those over the age of 75.

Literature Review

Reference ranges for most lab tests do not take into consideration age-
related factors that might affect results for the elderly, therefore, published
standards may be inappropriate. Studies to determine normal laboratory
values for elderly patients have been hindered by lack of healthy, aging
patients and the fact that many of these studies have taken place in
institutions where chronic disease is prevalent (Coodley, 1989). A case in
point is a decrease in glucose tolerance experienced by elderly persons that is
associated with a declining impairment in sensitivity and responsiveness to
insulin (Blair, 1990).

Diagnostic or laboratory manuals are employed in most primary care

settings in order to facilitate interpretation of the results, and most laboratory

results indicate the average (normal) reference range along with the actual
reading and an “H” or “L” to quickly identify “High” or “Low” readings.
Reference ranges are based on 95% averages with (+) or (-) two standard
deviations. Averages are based on findings of laboratory tests performed on,
for the most part, student subjects or younger adults (Melillo, 1993). These
may not be reflective of the findings that might be anticipated in a geriatric
population. It has been shown that many established reference ranges for
diagnostic tests are, indeed, appropriate for elderly patients. Other blood
tests, however, are affected by normal changes in aging, multi-drug regimens
and other factors such as exercise and nutrition.

Polypharmacy is a significant problem for geriatric patients. It is not
uncommon to find elderly patients taking a multitude of prescription and
non-prescription drugs. Haaksma (1995), in his Scholarly Project, reports
that multi-drug regimens affect elderly patients in many ways and that health
care workers must be aware of these effects on their elderly patients.
Keeping this in mind, accurate interpretation of laboratory values of elderly
patients who are taking a multitude of drugs is an important issue of concern
for the APN.

APN’s are often faced with a lack of standards when looking at values

for elderly patients and new reference ranges for geriatric patients should be
developed. Reference range refers to 95% distribution of the test results in
the reference population. This population is clearly defined in terms of age,
sex, race and health status (Duthie, 1991).

Cavalieri, Chopra and Bryman (1992) state that some lab values
change with age, while others do not. It has been reported in several studies
that ESR is altered with age and may increase as much as 0.22 mm/hr/yr.
Cavalieri, et al (1992) also have identified a decrease in glucose tolerance as
persons get older and report a post-prandial blood sugar increase of 70 mg/dl
from age 20 to age 75. In her studies on the interpretation of laboratory
values Melillo (1993) finds that gradual increases in cholesterol takes place.
Although they level off at approximately age 65, they remain higher than
those of younger adults even at age 85. Regarding magnesium, she states
that decreases in levels of as much as 15% have been found in patients
between the 3rd and 8th decades of life.

Changes of aging often influence laboratory test findings because of
specific physiological impacts upon the elderly person and other changes
which take place, such as the changes in nutritional status, decline in kidney

function, etc. Physiological changes that occur in this age range indicates a

10
decrease in cardiac and renal function, endocrine variations and alterations in
metabolism. An example is a decrease in glucose tolerance that is caused by
insulin being less biologically active. There is also an increased insulin

resistance with advanced age (Cavalieri, Chopra and Bryman, 1992).
Erythrocyte Sedimentation Rate (ESR)

ESR is frequently ordered in order to screen, diagnose and monitor
disease. It is a fairly simple test that measures the time that it takes for red
blood cells to settle at the bottom of a calibrated tube. It is reported in
millimeters/hour. Changes in plasma components cause the Erythrocyte
Sedimentation Rate (ESR) to become elevated. This elevation may or may
not be associated with disease, and changes in the amounts of albumin and
fibrinogen within the plasma may be the cause of the alteration. Other
factors that influence the speed with which the blood cells settle to the bottom
are concentrations of other plasma proteins (globulins), the size of the cells,
their shape and the actual number of erythrocytes.

This test is especially useful in diagnosing temporal arteritis and
polymyalgia rheumatica and is also useful in monitoring the course of

rheumatoid arthritis and Hodgkin’s disease (Ontario Association of Medical

l 1
Laboratories, 1995). McFarland and Grant (1994) found this test usefirl in
following the progress of inflammatory diseases such as rheumatoid arthritis,
rheumatic fever, respiratory infections and acute myocardial infarction.

Very high results of ESR are caused by multiple myeloma,
macroglobulinemias and hyperfibrogenemias. Other moderate increases are
neoplasms, chronic infections, collagen diseases and pregnancy (McFarland
and Grant, 1994).

Factors that tend to decrease ESR are sickle cell disease, polycythemia
and abnormal red blood cell structure (Helfgott and Kieval, 1995). Low
results also occur with errors in the testing procedure, i.e., allowing the
specimen to stand longer than three hours prior to testing.

In a test of men ages 20-81, it was noted that ESR did, in fact, increase
significantly with age (Cavalieri, et al, 1992) and that certain drugs are
responsible for increases in ESR values. Examples are: Procainarnide,
Theophylline, Methyldopa, which are prescribed regularly for elderly patients
with cardiac irregularities, Chronic Obstructive Pulmonary Disease (COPD),
and hypertension (Semia, Buzer and Higbee, 1995-96). Drugs that tend to

lower ESR levels are aspirin, cortisone and quinine (Mosby, 1995).

12

Serum Glucose

 

Endocrine changes may cause laboratory findings to be misinterpreted
due to a decrease in cellular sensitivity to insulin. (Blair, 1990). Peterson
(1994) states that diabetes mellitus is a classic misdiagnosis in the elderly
patient. Aging causes hyperglycemia that manifests as increased glucose
levels and may be caused by environmental or other factors and not,
necessarily, by disease. Malarkey and McMorrow (1996) report that glucose
levels should be adjusted by l mg/dl per year of life after sixty years of age.
This impaired glucose tolerance does not mean, however, that elders will not
experience health effects from elevated glucose levels and elderly patients
should be monitored for potential side effects related to these elevations.
Funnel] and Merritt (1993) note that diabetes may develop in about 20
percent of patients with IGT (impaired glucose tolerance).

Blood glucose is a measure of carbohydrate metabolism and identifies
the amount of sugar circulating in the bloodstream and whether or not
insulin, a hormone produced by the beta cells of the pancreas, is enabling
glucose molecules to move out of the bloodstream and into the liver and other

body cells (McFarland and Grant, 1994).

Capillary blood glucose testing has replaced urine glucose
measurement as a way for practitioners and patients to monitor glucose levels
and adjust dietary, insulin and exercise needs. It is convenient and easy and,
therefore, very useful to patients for monitoring their own therapy. It requires
collection of a drop of blood with a sterile lancet and placement of the drop
onto a specially prepared paper. It is then inserted into the glucose monitor
and the results are read within one minute.

Other forms of glucose testing are venous blood samples and the
glucose tolerance test which measures glucose levels at intervals of 30
minutes and 1 hour, 2 hours and 3 hours after ingesting an oral glucose
mixture. This is a more specific test that is usually performed to diagnose
potential diabetic conditions. With the exception of the glucose tolerance test
with specific testing intervals, serum glucose testing is done either in a 12-
hour fasting state (fasting blood sugar) or a 2-hour postprandial state (random
blood sugar). Researchers (Henry 1984; Byrne, Saxton, Pelekan and Nugent,
1986) state that plasma specimens collected twelve to fourteen hours after
eating show a decrease in variation among patients than those collected at
other times. The fasting blood sugar, then, is a more reliable indicator of true

blood sugars than those done on a random basis.

14

There are various reasons for elevated serum glucose. Many disease
states cause an elevation in blood glucose levels such as diseases of the
pancreas, tumors, acromegaly, Cushing’s syndrome, hyperaldosterism, etc.
Other causes are drugs (steroids, thiazide diuretics, propranolol, phenytoin,
diazoxide, oral contraceptives and alloxan and streptozotocin), chronic renal
states, chronic liver disease, infection, and abnormal insulin (Henry, 1984).

Regarding the elderly, Davidson (1979) states that the disposal of
glucose load is progressively impaired with the aging process and that five
possibilities exist which account for this change in insulin activity. They are:
(1) poor diet, (2) physical inactivity, (3) decreased lean body mass in which
to store the carbohydrate load, (4) decreased insulin secretion, and (5) insulin
antagonism.

Stress also plays a role in increased serum glucose results. Mosby
(1975) identifies these stressors as trauma, general anesthesia,
Cerebrovascular Accident (CVA) and Myocardial Infarction (MI). Caffeine
and drugs such as antidepressants, beta blockers, dextrose intravenous
infusion, dextrothyroxine, epinephrine, estrogens, glucagon isoniazid,
lithium, phenothiazines, phenytoin and triamterene , according to Mosby,

also increase serum glucose levels. Drugs that might decrease these levels

15
include acetaminophen, alcohol clofibrate, disopyrarnide, mao inhibitors,
propranolol, tolazamide, tolbutamide and insulin.

It is important for the APN to distinguish between hyperglycemia
which is a result of normal aging changes and diabetes mellitus. It goes
without saying that consistent, highly elevated glucose levels indicate disease,
however, there are many other factors to consider, especially in the elderly

population where aging changes and medications ofien alter test results.

Total Cholesterol

 

Cholesterol is a fat-like substance that is formed in the liver and
derived from ingested fats. It is found in brain tissue, blood and bile and is
synthesized in the liver and flows with the bile and eventually mixes with
dietary cholesterol. Free cholesterol is taken into the bloodstream and 70% is
combined with fatty acids to form cholesterol esters (Byrne, Saxton, Pelekan,
and Nugent, 1986).

Although cholesterol is not the cause of atherosclerosis by itself, it is
the lipoproteins with which it binds that form the plaque and cause occlusion
of the arteries. Two-thirds of this blood cholesterol is transported as low-
density lipoproteins (LDL) and a small amount is bound to high-density

lipoproteins (HDL). LDL is the “bad” cholesterol and increases in LDL are

16
related to development of CAD. Conversely, HDL is the “good” cholesterol
and high levels decrease the risk for coronary artery disease. These values,
along with triglycerides, are monitored in patients to determine risk factors
for coronary heart disease.

Ochs (1991) states that diagnostic testing for a baseline evaluation of
elderly patients should include a lipid profile. He firrther states that patients
with high cholesterol levels should be monitored at 3 to 6 month intervals in
order to monitor their response to therapy. Research findings indicate that
cholesterol levels rise significantly with age and that levels continue to rise
between the third and eighth decades (Cavalieri, et al, 1992). Leaf (1994)
states that hypercholesteremia contributes to Coronary Artery Disease (CAD)
that is the cause of death in more than 70% of those 75 years old and above.

The American College of Physicians recommends that total cholesterol
measurement take place once in early adulthood and every five years up to
age 70. The US. Preventive Services Task Force indicates that regular
measurement of total serum cholesterol is especially important for middle-age
men and that it is also significant for young men, women and elderly persons
(US. Public Health Service, 1995). In addition, the Second Report of the

Expert Panel on Detection, Evaluation and Treatment of High Blood

17
Cholesterol in Adults presented the National Cholesterol Education
Program’s updated recommendations for cholesterol management. This
report indicates that the addition of age to the list of major CHD risk factors
defined > 45 years in men and > 55 years in women. It firrther stated that
high-risk postmenopausal women and high-risk elderly patients, who are
otherwise in relatively good healthy, should be considered for cholesterol-
lowering therapy (National Cholesterol Education Program, 1996).

Cholesterol tests require collecting blood from patients after a twelve
hour fasting requirement. A venipuncture is then performed and two 7-ml
capacity tubes are filled. If the testing is a screening test only, a fmgerstick is
done using a sterile lancet (Malarkey and McMorrow, 1996).

The purpose of the serum cholesterol test is to identify patients who
might be at risk not only for CAD and M], but also to determine the
effectiveness of interventions that have been initiated in order to promote a
healthier lifestyle for those who might be at risk. Cholesterol levels are also
indicators of jaundice and other liver disorders. Elevated cholesterol levels
are seen with patients who have obstructive jaundice whereas low cholesterol
levels are found with infectious hepatitis and cirrhosis (Byrne, Saxton,

Pellekan and Nugent, I986).

l8

Medications have an effect on the results of cholesterol tests, and this
is especially significant with elderly patients. Clinicians should be aware of
this when looking at test results. Those which increase cholesterol levels are:
anabolic steroids, progestins, bile salts and chlorpromazine (US. Public
Health Service, 1995).

Conditions that affect cholesterol findings according to Malarkey and
McMorrow (1996) are: alcoholism, arteriosclerosis, diabetes, hepatitis, high
fat diet, myxedema, obstructed bile duct and pancreatitis. These all increase
cholesterol readings. Decreases are noted with patients experiencing
hyperalimentation, hyperthyroidism, liver disease, malabsorption and
malnutrition.

It is important to mention, however, that studies on cholesterol do not
only focus on high levels. In fact, recent studies have been done which have
looked at the relationship between low cholesterol levels in elderly patients
and impending death. Goichot, Schlienger, Grunenberger, Pradignac and
Aby (1995) have found that an increase in mortality rate is this age group has
been found in patients with low cholesterol concentrations.

According to Grant, Zdzislaw, Piotrowski and Miles (1996), low

serum cholesterol levels have been consistently related with increased short-

l9
term mortality among elderly in institutions. They further state that
declining levels have also been found with inflammatory illnesses such as
infections or neoplasms and that the decline in cholesterol levels of elderly,
prior to death, might be the result of many factors including catabolism,
anabolisrn, malnutrition or inflammatory processes. It is necessary for the
practitioner to be familiar with all factors that might be affecting a patient’s
cholesterol level, especially elderly patients, and to be able to interpret the

findings accordingly.

Serum Magnesium

 

Magnesium is an abundant intracellular cation that plays an important
role in the body’s metabolism. It is necessary to enhance cardiac contractility
and conductivity in the transmission of neurochemicals, in skeletal muscle
activity and in the maintenance of appropriate levels of intracellular calcium,
potassium and, potentially, sodium (American Diabetes Association, 1996).
To test magnesium levels, a 5-ml sample of venous blood is drawn in a plain
collecting tube and hemolysis is avoided when taking the collection. There is
no special fasting or diet required of the patient.

A reduction in magnesium creates a comparable reduction in other

20
enzymes affecting the entire system. Wood, Suster and Russell (1995)
indicate that low magnesium levels are linked with the pathOgenesis of many
diseases including ischemic heart disease, hypertension, osteoporosis, glucose
intolerance and diabetes. They further report that older women and men
consume less than RDA requirements of magnesium - approximately 2/3 of
the recommended amounts.

Magnesium imbalances are often found in geriatric practice especially
with patients having a decrease in nutritional intake and compromised renal
function (McFarland and Grant, 1994). Significant decreases have been
reported in patients and decreases of 15% between the 3rd and 8th decade of
life have been noted (Mellilo).

The American Diabetes Association sponsored a consensus conference
on magnesium supplementation in the treatment of diabetes May 15-16, 1992
and reported three main causes of magnesium deficiency: 1) excessive
urinary loss from diuretics or diabetic ketoacidosis; 2) a decrease in intestinal
absorption from severe diarrhea and small bowel resection; and 3) a decrease
in dietary intake.

The group also found that disease plays an important role in decreased

magnesium levels. Some of the diseases mentioned by this group,

2l
specifically, were hypertension, diabetes, perinatel morbidity in diabetic
pregnancies, arrhythmias and congestive heart failure. Mosby (1995)
reported that magnesium deficiency occurred in patients who were
malnourished and that excessive alcohol use increases the loss of magnesium
in the urine. Chronic renal diseases, hypoparathyroidism, hyperthyroidism
and hyperaldosteronism all play a role in lowered magnesium levels.

It is especially important to note with elderly patients that some drugs
also decrease magnesium levels: diuretics, antibiotics and insulin: all are
drugs commonly prescribed for older persons (Mosby, 1995). Additionally,
Byrne, Saxton, Pelekan and Nugent (1986) report an alteration of results with
dialysis therapy, digitalis intoxication, ethacrynic acid administration and
hypercalcernia.

Wood, Suter and Russell (1995) state that the amount of published
experimental data that identifies the magnesium needs of elderly people is
very limited and practically does not exist in those over the age of 85. It
becomes necessary, then, for the primary care practitioner to look at the
magnesium intakes of his/her elderly patients and identify whether the values

are appropriate and/or whether intervention needs to take place.

22

Conceptual Framework

In 1966 Virginia Henderson outlined her theory of nursing and
emphasized the unique function of nurses. She stated that a nurse must seek
to help the patient, in both sickness and health, in performance of activities
that will move him/her along a continuum to wellness or to a peaceful death.
Maintenance of independence is also identified as a major goal of nursing
care. Henderson also states that the nurse may need to assume many other
roles in order to meet patient needs (George, 1985). One of these roles is that
of assessor. Identification of laboratory results is part of the assessment
process and because the patient lacks the ability, for the most part, to
understand his/her test results, the practitioner must intercede.

According to Henderson’s theory, the nurse is a substitute for what the
patient lacks to make him/her complete, whole or independent. Virginia
Henderson emphasized that nurses must have a theoretical base for practice
and must be knowledgeable. Having the appropriate skills and education, the
APNs possesses the knowledge to understand and interpret for the patient the
pathological or normal conditions reflected in the patients’ laboratory tests.

Formulation of a plan then follows.

23

Fourteen components

The principal concepts of Henderson’s theory revolve around the 14
components of nursing that focus on individual care and self-maintenance.
They are guidelines for the patient as well as for those providing care, and are

essential to health maintenance, recovery or a peaceful death. They are:

I. Breathe normally.

2. Eat and drink adequately.

3. Eliminate body wastes.

4. Move and maintain desirable postures.

5. Sleep and rest.

6. Select suitable clothing - dress and undress.

7. Maintain body temperature within normal range by
adjusting clothing and modifying the environment.

8. Keep the body clean and well-groomed and protect the
the integument

9. Avoid dangers in the environment and avoid injuring others.

l0. Communicate with others in expressing emotions. needs.
fears, or opinions.

I 1. Worship according to one’s faith.

l2. Workinsuchawaythatthereisasenseofaeoornplishment.

13. Play and participate in various forms of recreation.

14. Learn, discover, or satisfy the curiosity that leads to
normal development and health and use of the available

health facilities. (Henderson, I955)

24
In the fourteen components of care, Henderson views the individual as

a bio, psycho, socio, and spiritual human being and identifies the unique
needs of the patient and the activities required to maintain a state of wellness.
Point #14 demonstrates the necessity of utilizing available health facilities.
When individuals avail themselves of health facilities, accurate assessment of
problems and appropriate interventions are expected. The practitioner is
responsible for making sure that this occurs. Henderson also notes that a
generalized education will give nurses a better understanding of those under
their care and a better identification of factors that might influence their
health. She further states that care must be practiced on an individual basis
and that nurses must be scientific problem solvers. This is significant in
interpretation of laboratory test results, especially within the elderly
population. Practitioners must have information available to assist them in
the assessment process. A protocol for assessment of laboratory findings of
elderly patients with adjusted reference ranges will be the foundation for
maintaining standards of practice and assisting the client in maintaining

optimal health and control of symptoms.

25

Nursing process

Henderson’s theory states that the application of logic to problem
solving is required in giving individualized care. The nurse must also assess
the true needs of the individual and must know what is normal or abnormal
in health and disease. “The nursing needed by the individual is affected by
age, cultural background, emotional balance, and his/her physical and
intellectual capacities” (Henderson, 1972). The practitioner must employ
logic in interpreting laboratory test results and, as Henderson reports, must
take several factors into consideration, i.e., metabolic changes, age, kidney
function. Age is specifically mentioned by the theorist as having an effect on
what is needed by the individual. It then becomes necessary for the
practitioner to identify “normal” from “abnormal” laboratory findings for the
aging individual. They must ask themselves if the reference ranges identified
in laboratory reports are actually “normal” or “abnormal” for a particular
elderly patient with potential kidney dysfunction, slower metabolism, cardiac

isabilities, polypharmacy, etc. With appropriate protocols in place regarding

 

 

Nurse As

Client
Advocate

 

 

 

 

Figure l. Henderson’s Theory of Nursing

accurate identification of values for older patients, a more comprehensive
plan of action can be formulated, based on metabolism, cardiac disabilities,
polypharmacy, etc. With appropriate protocols in place regarding accurate

identification of values for older realistic findings and needs identification.

 

Interpretation
of
Laboratory
Values

 

 

 

V

26

 

 

Client’s Health/Illness
Continuum

 

 

When the collected data is analyzed, a review of findings and

subsequent planning can begin. Henderson states that the nurse must identify

actual problems and must give thought to patient needs when doing so. The

27
planning phase must take into account the unique needs of the elderly patient
and the plan must be specific and fit the individuals themselves. When the
plan is put into place, then appropriate actions can be taken to improve
patient health or maintain the status quo.

Within the planning stages, the APN must have a foundation for the
interventions set forth. By correctly identifying the patient’s laboratory
results, the plan of care will become more appropriate, more reliable and
more individualized to patient needs. Nursing process is based on a logical
approach to patient care and an understanding of diagnostic values is part of
the assessment and planning process.

As part of an interdisciplinary health care team, it is the responsibility
of the advanced practice nurse to identify accurate laboratory values for
elderly patients. Polypharmacy and over-treatment of these individuals are
often a major problem in primary care. By using a holistic approach the
APN is able to minimize these problems and plan and implement a plan of
care that is based upon recognizing the person as an individual with unique
needs. A protocol identifying accurate reference ranges for four frequently
used laboratory tests, Erythrocyte Sedimentation Rate (ESR), Serum

Magnesium, Total Cholesterol and Serum Glucose, is a step forward in

 

Nursing Emotions

-Assessor
~Advocate

 

 

 

 

Use of
Healthcare
Facilities

 

 

 

 

Interpretation
of
Laboratory Values

 

 

 

Figure 2. Model For Interpretation of Laboratory Values

28

29
maintaining accuracy in assessment and implementation of a plan for

geriatric patients as based on Virginia Henderson’s theory of nursing.

Development of the Project

Purpose

The purpose of this Scholarly Project is to formulate a protocol for
APN’s to enhance accurate interpretation of laboratory test results for elderly
patients. This protocol may be utilized in private practices, clinics, nursing
homes and other primary care settings. It will outline the appropriate
reference ranges for geriatric patients for Erythrocyte Sedimentation Rate
(ESR), Serum Glucose, Total Cholesterol, and Serum Magnesium.

Based on the current literature, guidelines will be formulated with
revised reference ranges for elderly patients. The guidelines will present
more appropriate reference ranges for the laboratory tests in this study, based
on current research and investigation.

The protocol will include the reference ranges for adults for each
specific test and adjusted ranges for adults above the age of 65. It will also
present a brief explanation of the test, including reasons for ordering, and

factors that might affect the results, such as disease or drugs.

30

An understanding of the effects of aging on laboratory values will
increase the APN’s ability to correctly diagnose the patient in primary care
and begin appropriate interventions. Without accuracy in interpretation of
these laboratory tests, the advanced practice nurse is not able to firlfill his/her
commitment to holistic care.

The laboratory tests included in this study are frequently ordered in
primary care practice and, too often, age-related factors are not taken into
account when analyzing the results of the data. This leads to errors in
diagnosing and treatment of elders.

As traditional thinking about aging changes, so does the distinction
between normal aging and disease process. It is important for the APN to
distinguish between disease and/or age changes in his/her patients who are
reporting symptoms (Peterson, 1994). The protocol will be developed in
order to better identify appropriate reference ranges for Erythrocyte
Sedimentation Rate (ESR), Serum Glucose, Total Cholesterol and Serum
Magnesium for elderly patients and, accordingly, initiate appropriate

interventions.

31

Procedure

The APN in primary care is responsible for the assessment of patient
symptoms and utilizes laboratory tests to increase diagnostic accuracy and
maximize the appropriateness of interventions. The protocol will assist the
APN to better interpret the results of laboratory testing and will serve as a
guideline for him/her to refer to when working with elderly patients.

The protocol may be used by other health care providers and when
accessible, will serve as an important reference point for all who utilize
laboratory test results. The protocol is intended to be used in many settings
and is appropriate in private practice, acute care facilities, ambulatory clinics,
long term care facilities and various other health care settings.

The protocol will be specific to patients over the age of 65 and will be
formated as follows; the name of each test will be listed in Column 1. The
next column will identify reasons for ordering the test, such as ruling out
certain diseases, identifying the efficacy of health promoting activities or
confirming suspected diagnoses. The third column will present the current,

normal, reference ranges for adults and the last column will identify the

32
revised reference ranges for adults above the age of 65.

In addition, each test will have an accompanying interpretation of
results with explanations of values falling outside of the reference ranges.
Explanations for both high and low values will be presented in sequential
fashion and organized by physiological factors, drugs which might affect the
results and disease processes. Signs and symptoms of low or high values for
each particular test will also be included, if appropriate.

The protocol may be placed in examination rooms, charts, procedure
manuals, at nurse’s stations, medical carts or lab rooms. It should be easily
accessible for all who are responsible for the patient’s care and will serve as a
guide to a more accurate interpretation of lab values. As Cavalieri, et al
(1992) state, “To ensure prOper assessment of the geriatric patient, the
clinician needs to be aware of age-related changes and their effect on
laboratory values.” The protocol will maximize geriatric assessment and

enhance patient care.
Evaluation of the protocol

The protocol could be evaluated, first, by a review of 100 charts of

elderly patients in a primary care setting. The instances in which the tests

33
were ordered could be identified and test results of ESR, Serum Glucose,
Total Cholesterol or Serum Magnesium examined. Next, signs and
symptoms presented by patients and their treatments could be compared for
those with similar lab results.

Comparisons could then be made between patients prior to and after
the protocol. An analysis of the number and types of treatments ordered and
the results of the interventions could be looked at and a determination made
as to the validity of the revised reference ranges for elderly patients and
whether or not the protocol was being utilized.

In addition, a panel of practicing APN’s could review the protocol for
its effectiveness and usefulness in practice. A determination could also be
made regarding the appropriate format for the guidelines, i.e., the most useful
presentation and placement of the document.

Implications for the future

Interpretation of laboratory values for elderly persons is complicated by
a number of factors including underlying disease, anatomic changes in the
elderly, drug use and the effects of diet and nutrition on laboratory tests
(Coodley, 1989). As trends indicate, the number of elderly within the

population is increasing at a significant rate and increasing numbers are

' 34
being seen in primary care facilities. The correct interpretation of laboratory
tests in this population will continue to be of increasing importance to the
APN in the future when diagnosing problems and planning interventions.

Melillo (1993) has reported that health professionals must not treat
abnormal laboratory values that may only represent altered physiological
states and not true disease or pathological disorders. As a result, the APN
must be aware of the physiological changes that take place with elderly

patients and adjust treatment for these patients accordingly.

Education

 

Nursing school curriculums could include a teaching module regarding
adjusted laboratory values in geriatric programs. In this way, the students
would be better prepared and alert to changes which might affect test results
for their patients. Similarly, inservices and training sessions in current
practices, in all levels of care, would be a step in the right direction in
assisting staff to use critical thinking in the assessment of laboratory values.
Cavalieri, et a1 (1992) state that clinically significant changes may be
incorrectly attributed to age alone by health care professionals and changes
that are normal with aging may be misinterpreted as signs of disease by this

same group. This information becomes critical, then, for education of health

35
care providers in providing optimal care to their patients.
Research

There is a lack of research on laboratory values for elderly patients.
Melillo (1993) reports scant literature on the subject and Kelso (1990)
reiterates the paucity of data on reference values for healthy, elderly persons.

At present, there is limited reference to normal ranges for persons over
the age of 65 for ESR, Serum Glucose, Total Cholesterol and Serum
Magnesium. Further studies need to be undertaken to refine appropriate
reference ranges for other laboratory values as well. There have been
indications regarding the need for new guidelines for Uric Acid, Creatinine
Clearance and Hemoglobin, Hematocrit and Red Blood Cells. Melillo (1993)
reports wider ranges and lower values than those for younger adults in the
geriatric population.

There is also a lack of data regarding the value of routine laboratory
tests in older adults. Kim and Berlowitz (1994) state that routine
comprehensive laboratory panels may not be warranted in severely impaired
elderly patients in long-term care facilities. They have found that laboratory
assessments limited to assessing acute changes in clinical status might be

more appropriate for these patients as well as being more cost effective.

36
There is a need for more research in the area of normal laboratory values in
geriatric populations.
Summgg

The APN has a responsibility to the patient to provide optimal care
while making appropriate use of health care resources. He/she will be able to
improve the quality of care for his/her patients by correct interpretation of
ordered lab tests. This will allow for more accurate diagnoses, decreased
number of office visits, and increased patient satisfaction. Costs for needless
interventions are also contained, which is a significant issue in health care at
the present time.

Advanced practice nurses treating the elderly in primary care, have
access to many non-invasive and invasive procedures as well as high
technology devices in order to accurately diagnose and treat their patients.

An understanding of the effects of age on laboratory values has been lacking
in the literature. This is especially true for the population of elderly over the
age of 75 which, at present, includes the fastest growing segment of the aging
population. Ochs (1991) indicates that, with elderly patients, the selection of
the proper test is essential in meeting patient needs and that the decision must

take into account not only the suspected condition, but the diagnostic value of

the test, the skill required to perform it and the cost of the test itself.

A research-based protocol delineating the adjusted “normal” laboratory
values for geriatric patients is a positive step in promoting accurate
diagnosing and appropriate treatment interventions for the elderly. As
Melillo (1993) states, “Health care providers who work with the elderly are
faced with a lack of aggregated standards with which to compare patient
values.” It is the intent of the author to provide an acceptable standard of

values for elderly patients which will be useful to all primary care providers.

38

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Wesley Publishing Co.

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Coodley, E. (1989). Laboratory tests in the elderly. What is

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metabolism: a review of the English literature and a practical approach to the

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laboratory tests and diagnostic procedures. Phila, PA: WB Saunders, Co.

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McFarland, M. and Grant, M. (1994). Nursing Implications of

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APPENDIX

LABORATORY VALUES FOR ESR,
SERUM MAGNESIUM, TOTAL CHOLESTEROL

Laboratory Test

ESR (Erythrocyte
Sedimentation Rate)

Serum Magnesium

Total Cholesterol

Serum Glucose (Two-
Hour Post Prandial)

AND SERUM GLUCOSE

Adult
Reason for Ordering Test Reference Range
To identify and monitor 0-15 mm/hr
disease activity in infectious, for males
inflammatory and neoplastic
conditions. Especially 0-20 mm/hr
useful in detecting for females
rheumatic and collagen
disease.
To evaluate electrolyte 1.2-2.5 mEq/L
disorders, hypocalcemia,
and acid-base imbalance.
To monitor cardiac
disorders.
To identify persons at risk < 200 mg/dl
for CAD and to determine
the effectiveness of health
promoting lifestyle changes.
To evaluate insulin response 70-145 mg/dl

to glucose intake and to
evaluate the management of
diabetes mellitus.

43

>Age 65
Reference Range

0

0-20 mm/hr
for males

0-30 mm/hr
for females

0.5-.78 mEq/L

<212-214 mg/dl
for males

<202-233 mg/dl
for females

100 mg/dl &
patient’s age

LABORATORY TEST

ESR (Erythrocyte
Sedimentation Rate)

CAUSES OF HIGH
VALUES

Disease:

multiple myeloma
neoplasms
chronic infections
collagen disease

Drugs:
dextran
methyldopa
contraceptives
penicillarnine
procainamide
theophylline
vitamin A

Other:

pregnancy.
menstruation

changes in albumin &
fibrinogen in plasma
elevated glucose levels
high cholesterol

Signs & Symptoms:
disease related

44

CAUSES OF
LOW VALUES

Disease:

sickle cell disease
polycythemia

abnormal red blood cells

Drugs:
aspirin
cortisone
quinine
ACTH

Other:
specimen allowed to stand
longer than three hours

Signs & Symptoms:
disease related

Serum Magnesium

Disease:
chronic renal failure
Addison’s disease

Drugs:
magnesium sulfate
sedatives

antacids

enemas

milk of magnesia

Signs & Symptoms:
decreased nerve and muscle
activity

lethargy

decreased perspiration
coma

cardiac arrest

45

Disease:

renal disease

diabetes
hypoparathyroidism
hyperaldosteronism
pancreatitis

ischemic heart disease
osteoporosis

diarrhea

congestive heart failure

Drugs:
diuretics
antibiotics

insulin

Other:

decrease in calcium and
potassium

decreased nutritional intake
malabsorption
maldigestion

alcohol abuse

Signs & Symptoms:
tremors

parasthesias

weakness

tetany

increased blood pressure
increased heart rate
convulsions
disorientation

Cholesterol

Disease:
arteriosclerosis
CAD

alcoholism

diabetes mellitus
myxedema
obstructive bile duct
pancreatitis
obstructive jaundice

Drugs:

anabolic steroids
progestins

bile salts
chlorpromazine
beta adrenergic blockers
corticosteroids
epinephrine
phenytoin
sulfanomides
thiazide diuretics
vitamin D

Other:
high fat diet

Signs & Symptoms:
disease related

46

Disease:
hyperthyroidism
liver disease
hepatitis

cirrhosis

sepsis

pernicious anemia

Drugs:
fluvastatin
lovastatin
niacin
probucol
mao inhibitors
allopurinol
androgens
captopril
colchicine
erythromycin
isoniazid

Other:
hyperalimentation
oophorectomy
malabsorption
malnutrition

*An increase in short-term
mortality has been found
with elderly patients and
decreases in cholesterol
levels.

Signs & Symptoms:
disease related

Blood Glucose (Two-Hour
Post Prandial)

Disease:

diabetes mellitus
CVA

MI

Cushing’s disease
hyperparathyroidism
adenoma of pancreas
pancreatitis

Drugs:
antidepressants

beta adrenergic blockers
corticosteroids
dextrose IV solutions
dextrothyroxine
diazoxide

diuretics

epinephrine
estrogens

glucagon

isoniazid

lithium
phenothiazines
phenytoin

salicylates
triamterene

Signs & Symptoms:
polyuria
polydipsia
polyphagia

weight loss

fatigue

hunger

47

Disease:
insulinoma
hypothyroidism
hypopituitarism
liver disease

Drugs:
acetaminophen
alcohol
anabolic steroids
clofibrate
desopyramide
insulin

mao inhibitors
pentamidine
propranolol
tolazarnide
tolbutamide

Signs & Symptoms:
sweating
nervousness
increased pulse
headache

loss of conscience
convulsions

 

31293 .02369 I9600 _