Transcript Anemia_ABC_s

ANEMIA
September 17th, 2011
Debra Wells BSN, RN, CNN
Objectives
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Describe the symptoms of anemia, clinical
complications and how they relate to the
quality of life of dialysis patients
Describe the pathophysiology of anemia in
dialysis patients.
Review the use of erythropoiesisstimulation agents (ESAs) and iron agents
and review nurse role in evaluating
anemia in the dialysis patient
Definition
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Anemia is a condition in which there are a
decreased number of healthy red blood
cells to carry adequate oxygen to tissues
and cells.
Symptoms of Anemia
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Increased cardiac workload, LVH, tachycardia,
dyspnea, palpitations, angina, fatigue
CNS symptoms: anorexia, insomnia, peripheral
numbness, decreased mental acuity
There is widespread tissue hypoxia, mucous
membranes and skin are pale, skin loses
elasticity, tissues atrophy
Exercise intolerance, limiting work capacity,
decreased quality of life
Red Blood Cell
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It’s sole purpose is to transport
oxygen from the lungs to the
tissues.
It cannot replicate because it
does not have a nucleus
It is formed in only one placethe bone marrow
Under normal circumstances it
lives for 120 days.
The most important
component of the red blood
cell is Hemoglobin
Hemoglobin
Hemoglobin Molecule
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Oxygen is not very soluble in
water (the major constituent
of blood), and thus an oxygen
transport protein must be used
to allow oxygen to be 'soluble'.
Hemoglobin (Hb) is the oxygen
transport protein used in the
blood.
Hb picks up oxygen at the
lungs and delivers it to the
tissues. Hb is able to both bind
and release oxygen and is able
to do these at the right places!
Heme Group
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The iron is the site of oxygen
binding; each iron can bind
one O2 molecule thus each
hemoglobin molecule is
capable of binding a total to
four (4) O2 molecules.
Without iron in the heme
group, there would be no
site for the oxygen to bind,
and thus no oxygen would
be delivered to the cells
Normal RBC Production
Normal RBC Production
Erythropoetin
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Erythropoetin (EPO) is a hormone
produced and secreted from the kidney in
response to hypoxia. It travels to the
bone marrow and stimulates the
production of red blood cells.
Minimal Serum Iron levels needed
with normal kidney function
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Ferritin
Iron storage
24ng/ml
Iron Saturation (TSAT)
available iron
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14%
Normally enough iron is available from ingested
food or oral iron preparations.
Pathogenosis of anemia of CKD
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Erythropoetin deficiency
Decreased RBC survival time
Caused by uremic toxins (transfusion study)
Average lifespan 60 days
Blood loss from platelet dysfunction
Dialysis patient has additional reasons for anemia
Frequent lab drawings
Higher incidence of GI bleeding
Blood loss from poor dialyzer clearance
Vitamins lost through dialysis
Frequent surgery
Infection
Retention of inhibitors, PTH, Aluminum
IRON
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Causes of iron deficiency in CKD
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Decreased iron intake due to decreased total dietary intake
of protein.
Absorption of iron from the intestines is diminished
making oral iron supplements ineffective.
Certain medications, such as drugs that decrease gastric
acidity, and certain foods can decrease iron absorption.
Each 1 ml loss of red blood cells results in the loss of 1 mg
of iron. Dialysis patients may lose up to 2g of iron each
year as a result of blood loss due to lab testing, GI
bleeding, retention of blood in the dialyzer and lines and
bleeding of the access.
Treatment with EPO will also cause iron deficiency.
Impaired RBC production
Erythropoesis Stimulating Agents (ESA’s)
and Intravenous iron
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These medications greatly improved the majority of
patients lives by correcting anemia and reducing need
for transfusions
However, pharmacologically induced erythropoesis
requires careful monitoring and adjustments.
And it is difficult to mimic the body’s normal mechanism
of iron delivery with an iron administration regimen and
patients responses to ESA’s vary.
Most Dialysis units create nurse driven protocols with
specific directions for multiple scenarios.
Some units utilize an anemia manager.
ESA Therapy Protocols
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Choice of ESA
Route and frequency
Should be dosed per kg of body weight
Target Hb levels-recent CMS target goal was
lowered to 10-11g/dL
Hb monitoring schedule-at least once a month
Hb variability is common in dialysis patients
Dose adjustment criteria
Iron Deficiency
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Labs required for iron evaluation
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Transferrin saturation (TSAT) refers to readily available iron.
Serum Ferritin refers to stored iron.
Absolute iron deficiency is defined as tansferrin saturation
(TSAT)<20% and serum ferritin <200microg/L.
Functional iron deficiency exists when iron is used up faster than
can be transferred from storage (ferritin). Transferrin saturation
would be less than 20% and ferritin approximately 300-500.
Inflammation block exists when the TSAT abruptly decreases along
with an abrupt increase in serum ferritin. This is caused by an
acute or chronic inflammation or infection.
Iron Therapy Protocols
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Choice of Intravenous iron product
Target levels
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TSAT goals-most protocols use 25% or even 30% as lower limit
and 50% as upper limit
Serum ferritin-varies and is considered less important in iron
administration protocols. Lower limit is usually 500ng/ml and
upper limit 1200ng/ml
If levels are below lower limits, usually loading doses of iron are
recommended.
If iron levels are in target, maintenance doses are needed to
ensure iron repletion.
If iron levels are above limits, iron should be held temporarily
until next set of iron labs are drawn.
Nursing Assessment
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Managing anemia requires more than just
following ESA and iron protocols
After hospitalization there is often blood loss. It
is recommended to re-evaluate hb and iron labs
It is important to look at trending of hb and iron
labs
If there are sudden decreases in hb or iron labs
a nursing assessment is needed and MD should
be contacted.
Not Responding to Therapy
Protocols?
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Hyporesponsiveness to ESA
Bone marrow dysfunction
Inflammatory disease
Infection
MD’s may order therapy outside of protocol
Some patients such as those receiving
chemotherapy for malignancy may require
transfusions
Conclusion
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Anemia management is an important aspect of
care for CKD patients which has these benefits:
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Lowers mortality and hospital rates
Improves CHF and LVH
Reduces the need for Transfusions
Improves Quality of Life
In addition to carefully following protocols, it is
important to evaluate the patient’s medical
status and treat the underlying etiology.