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Classification and management of anaemiaOlasinde Yetunde
Introduction
• Anemia is defined as a reduction of the red blood cell (RBC)
volume or hemoglobin concentration below the range of values
occurring in healthy persons.
• Anemia is any value for the hemoglobin or hematocrit that is 2
SDs below the mean for age and sex.
Introduction
Race:
Inherited red cell disorders are predominant in certain racial
populations-
Sickle cell disease in black persons, Beta thalassemia in people of
Mediterranean
descent
Sex:
• In developing countries, the prevalence of anemia is extremely
high.
• Iron deficiency, malaria and malnutrition have been recognized as
the major contributing factors.
• Mortality and morbidity rates vary according to the underlying
pathologic process causing the anemia, the degree of severity, and
the acuteness of the process.
Introduction
Cord blood 16.8 13.7–20.1 55 45–65 5.0 110
2 wk 16.5 13.0–20.0 50 42–66 1.0
3 mo 12.0 9.5–14.5 36 31–41 1.0
6 mo–6 yr 12.0 10.5–14.0 37 33–42 1.0 70–74
7–12 yr 13.0 11.0–16.0 38 34–40 1.0 76–80
ADULT Female
Hematologic Values During Infancy and Childhood
• Although the reduction in the amount of circulating hemoglobin
decreases the oxygen- carrying capacity of the blood, few clinical
disturbances occur until the hemoglobin level falls below 7–8
g/dL.
• Below this level, pallor becomes evident in the mucous
membranes
Physiologic adjustments to anaemia
• shunting of blood flow toward vital organs and tissues.
• concentration of 2,3-diphosphoglycerate (2,3- DPG) increases
within the RBC
Physiologic adjustments to anaemia
• The resultant “shift to the right” of the oxygen dissociation
curve reduces the affinity of haemoglobin for oxygen and results in
more complete transfer of oxygen to the tissues.
• Increase in erythropoietin production to stimulate RBC
production.
• Few clinical features before Hb level < 7-8g/dl
• Moderate to severe anaemia develops slowly.
• Weakness, tachypnea, shortness of breath on exertion,
tachycardia, cardiac dilatation, and congestive heart failure
ultimately result from increasingly severe anaemia.
• Hypoxaemia can lead to
Normochromic normocytic
Hypochromic microcytic
Normochromic macrocytic.
– Fanconi, aplastic anemias, Mitochondrial dx,
myelodysplasia.
Normal Macrocytic
• increased red cell destruction (hemolysis)
• blood loss
– more than 1 mechanism may be involved
• develops gradually and causes chronic anemia. Marrow failure may
result from the following:
• Diamond-Blackfan anemia (congenital pure red cell aplasia)
• Transient erythroblastopenia of childhood
• Aplastic anaemia
• Aplastic crisis caused by parvovirus B19 infection (in patients
with an underlying chronic hemolytic anemia)
• Anaemia of chronic disease (shortened lifespan, blunted response
to EPO, decreased Fe absorption)
• Renal disease
Extracellular causes-
• Infections, drugs, toxins
Excessive destruction of red blood cells
Excessive destruction of red blood cells
Intracellular causes-
• Hemoglobinopathy – Thalassemia
• Reticulocyte increased
Blood loss
• Obvious or occult site of blood loss: GI tract, intra-abdominal,
pulmonary, intracranial (in neonates)
• Massive hemorrhage (internal or external) for patients with
bleeding disorders.
• NEONATES
• INFANTS
o Malnutrition
• Quick history
• Physical examination
give IV N/saline
– Urgent group & crossmatch blood for transfusion
Management
• Anaemia is not a diagnosis but rather a clinical manifestation of
an underlying condition.
• Treatment of the anaemia is as important as is the search for the
aetiology.
• The role of a detailed history and physical examination can not
be overemphasized.
HISTORY
• Haemolysis : – jaundice, dark urine, fever, family history
of
haemolytic disorders e.g haemoglobinopathies, enzymopathies,
membranopathies.
• Residence or visit to malaria endemic area
• Exposure to oxidant drugs and chemicals
History
• Decreased production/ ineffective erythropoiesis • Diet
Cow milk based diet – iron deficiency Vegetarian – B12 deficiency
Dietary perversions (pagophagia, picca) – fe deficiency,
plumbism
• Age of patient e.g iron deficiency rare without blood loss under
6 months.
• History suggestive of chronic renal impairment, • Malignancies:
pallor, pain, pruritus, pyrexia, petechiae,
lymphadenopathy.
History
deficiency • Previous gut resection- iron, B12 deficiency. •
Parasitic infestation e.g giardia, fish tapeworm – iron and
B12 deficiency • Slapped cheek appearance – parvovirus infection •
Impaired proprioception, paraesthesia – vit B12 deficiency
PHYSICAL EXAMINATION
GENERAL EXAMINATION
• Mees line (nails) - Heavy metals, severe illness, sickle cell
anaemia
• HEAD
• Frontal bossing - SCD, Thalassemia major, severe iron deficiency,
chronic subdural hematoma
GENERAL EXAMINATION
blood loss)
GENERAL EXAMINATION
disease, extramedullary hematopoiesis • Splenomegaly - Hemolysis,
sickle cell disease,
thalassemia, malaria, lymphoma, Epstein-Barr virus • CNS •
Irritability, apathy - Iron deficiency • Peripheral neuropathy -
Deficiency of vitamins B12 &
E, Lead poisoning • Ataxia, posterior column signs - Vitamin B12
deficiency • Stroke - Sickle cell anemia,
INVESTIGATIONS
• Hinged on findings in history and physical examination.
• A complete blood count and peripheral blood film examination to
highlight haematocrit, MCV and reticulocyte count are basic.
• Reticulocte production index – assesses bone marrow response
(adequacy of reticulocyte production) to anaemia. – Normal
2-3
• Other investigations to be guided by history and examination
findings.
Treatment options
• Red cell substitutes
• Leucocyte reduced or depleted red cells
• Washed red cells
Whole blood
• A unit – 510mls( 450mls of WB + 63 mls of CPDA with shelf life of
35 days and Haematocrit 0.35-0.40)
• 6ml/kg of whole blood will raise Hb by 1g/dl
• Transfusion should be completed within 4hrs
Indications for whole blood
• Rapid massive blood loss
• Packed cells produced when RBCs are separated from whole blood
after centrifugation and re-suspension in an
anticoagulants/preservative solution at haematocrit of 60%
• Preferred to whole blood in patients with cardiovascular
compromise
• Useful in patients with chronic anaemia
Red cell transfusion
• 1 unit of pRBC is about 300-350mls will raise an adult Hb by
1g/dl or haematocrit by 2-3%
• In paediatrics - 3ml/kg of packed cell raise HB by 1g/dl
• 10mls/kg of transfusion will raise Hb by 3g/dl and haematocrit by
10%
• Complete transfusion in 2-4 hours
Leucocyte reduced or depleted red cells
• Carried out by use of leucocyte filters or irradiation of blood
products.
• Used in preventing non-haemolytic febrile transfusion
reactions.
Washed red cells
• Itis indicated in Paroxysmal nocturnal haemoglobiuria (washing
removes complement component that causes RBC lysis).
• Should be used within 24hrs
Commonly used transfusion products
• Recombinat human erythropoietin (rHuEPO) is a synthetic
glycoprotein hormone that controls erythropoiesis.
• It is a protein signaling molecule for erythrocyte precursors in
the bone marrow
• It is given at a dose of 50–150 mg/kg/dose subcutaneously 1-3
times weekly
• In one week it will raise Hb by 1g/dL
Action of erythropoietin
Complications of rHuEPO
• Clotting of vascular access
• Pure red cell aplasia (reported in adults due to recombinant
human erythropoietin antibodies)
• Tumour recurrence when used in cases of malignancy
Aids of red cell synthesis cont.
• Haematinics
– Iron: A daily total dose of 4–6 mg/kg of elemental iron in 3
divided doses provides an optimal amount of iron for the stimulated
bone marrow to use.
– The response to parenteral iron is not more rapid or complete
than that obtained with proper oral administration of iron
Iron cont.
–Within 72–96 hr after administration of iron to an anemic child,
peripheral reticulocytosis is noted
– Increase in Hb level will occur between 4 – 30 days
–Hb rise is about 0.5g/dL/day after day 4
Other haematinics
• Folic acid
• Vitamin B12
RED CELL SUBSTITUTES They are artificial oxygen carriers and are
still under clinical trial.
• Perfluorocarbons
• Diaspirin
hypocalcemia, hypothermia, alkalosis)
COMPLICATIONS OF TRANSFUSION
• Bacterial infections
• Acute hemolytic transfusion reaction Clinical presentation Fever,
Chills, rigors, Apprehensiveness Pain in the lower back, flanks,
chest and along infusion vein Hypotension, Bleeding, Disseminated
Intravascular
Coagulation, bloody or dark urine, Renal failure
• Laboratory findings: Hemoglobinemia Hemoglobinuria Positive
direct antiglobulin (Coombs) test
MANAGEMENT OF TRANSFUSION REACTIONS
• Management • STOP TRANSFUSION • IV normal saline 20mls/kg to
maintain optimal renal
perfusion. • Give steroid: IV Hydrocortisone • Possible need for
dopamine if hypotension develops • Monitor vital signs, urine
output • Recheck donor and recipient details on the form and
blood
bag. • Return unit(s) to blood bank along with patient’s
post-
transfusion blood samples and completed transfusion record.
MANAGEMENT OF TRANSFUSION REACTIONS
• At blood bank • Direct Coombs test on posttransfusion specimen. •
Examination of posttransfusion plasma for hemolysis.
If acute hemolysis is suspected: • Repeat ABO and Rh testing •
Repeat crossmatch with implicated unit(s) • Repeat antibody
screening tests • Repeat DAT and antibody screen on additional
specimens
obtained at intervals after the transfusion reaction • Fresh pint
of blood or blood component if transfusion still
indicated.
• Febrile non-hemolytic transfusion reaction • A diagnosis of
exclusion made ruling out Acute Hemolytic
transfusion Reaction(AHTR). • Usually arise from interaction
between donor/recipient white cells
and preformed antibodies Clinical presentation Fever, Chills,
rigors, headache, nausea, vomiting Management
Very vital to rule out AHTR, hence manage as earlier outlined.
Acetaminophen can be given; condition usually self limiting. If
haemolysis is ruled out and fever resolves, transfusion can be
recommenced.
If fever/rigor recurs, order a fresh pint.
MANAGEMENT OF TRANSFUSION REACTIONS
• Allergic transfusion reaction • CLINICAL PRESENTATION •
Cutaneous: Urticaria, Pruritis, Flushing, Facial edema, Angioedema
• Respiratory:Wheezing Stridor Dyspnea Cough • Cardiovascular:
Hypotension • Loss of consciousness • Gastrointestinal: Nausea
Vomitting Abdominal cramp • Management: • Lab work up as for AHTR.
• For mild reactions e.g localized urticaria, transfusion can be
continued
after administation of anti-histamins with resolution of symptoms.
• If symptom other than this is present, discontinue the pint of
lood. • Management of severe form mainly supportive and may
necessitate use of
adrenaline , B-agonists & oxygen.
• Delayed haemolytic transfusion reactions • Onset is variable but
usually occurs within the first two
weeks following transfusion. • Characterized by an unexpected
anemia or a less than
expected post-transfusion increment in hematocrit following
transfusion.
• Other symptoms include fever or chills, jaundice, malaise, and
back pain; renal failure rarely occurs.
• Treatment – Mainly supportive. Adequate hydration, may require
repeat
transfusion.