Anaemia Overview Flashcards
Definition of anemia
Reduction in O2 carrying capacity of the blood
Define anemia in adult males according to WHO standard
Hb less than 13g/dl in adult males
Define anemia in adult females according to WHO standard
Hb less than 12g/dl
Define anemia in children according to WHO standard
Hb less than 12g/do (6-14yrs)
Define anemia in neonates according to WHO standard
Hb less than 13.5g/dl
Ambient O2 may be affected by altitude T/F
T
Ventilation may be affected by
Poor ventilation perfusion ratio and anatomical dead space
What is the O2 tension of blood
20 volume%
In the arterial blood, O2 tension is approximately
20 vol%
In the venous blood, O2 tension is approximately
15 vol%
Arteriovenous O2 difference equals
5 vol%
Anemia tends to reduce arterio-venous O2 difference T/F
T
List the 4 adaptations to anemia
- Modulation of Hb O2 affinity
- Redistribution of blood flow
- Increase CO
- Reduction of venous O2 tension to increase Arterio-venous O2 difference
To modulate O2 affinity, what compound is increasingly produced to bind and stabilize Hb in its DEOXY form?
2,3 DPG
The Hb on red cells during anemia is (pH)
Alkaline
Alkalosis stimulates the production of what enzyme
1,3 DPG mutase
The modulation of O2 affinity promotes what pathway
Rapapport-Lueberig shunt of amended-Myerhoff pathway
1,3 DPG mutase converts 1.3 DPG to
2,3 DPG which binds and stabilizes Hb in its deoxy form allowing O2 to be delivered to the tissues.
Other conditions associated with increased 2,3 DPG production
- Hyperphosphataemia
- Renal failure
- Altitude hypoxia
- Pregnancy
- Cyanotic Congenital Heart disease
- Thyrotoxicosis
- Some red cell enzyme deficiencies
Conditions associated with reduced 2,3 DPG production
- Acidosis
- Cardiogenic shock
- Septicaemic shock
- Hypophosphataemia
- Hypothyroidism
- Transfusion with stored blood
Anemia causes profound *vasoconstriction/vasodilation *
Vasodilation
Anaemia causes increased/decreased peripheral resistance
Decreased
Anaemia causes narrow/wide pulse pressure
Wide
Increased/Decreased blood flow to myocardium
Increased
Increased/Decreased Stroke volume
Increased
In anemia, there’s Increased/Decreased heart rate
Increased
Increased/Decreased Cardiac output
Increased
Increased/Decreased whole blood viscosity
Decreased
Increased/Decreased circulatory time
Decreased
Signs of failure of cardiovascular adaptive mechanisms
Palpitations
Angina of effort
Increased arterial pulsation
Capillary pulsation
Haemic murmurs
Basal crepitations
Cardiomegaly
Peripheral oedema
Ascites
Aetiology of anemia
Blood loss
Decreased survival or rbcs
Bone marrow failure
Anemia of blood loss - Acute losses
RTA
Surgery
Massive Antepartum Haemorrhage
Massive Postpartum Haemorrhage
Ruptured Ectopic
DIC
Chronic Losses from the GIT can cause anemia. List diseases that cause haematemesis
Hiatus hernia
Chronic Duodenal ulcer
Gastric cancer
Salicylate ingestion
List diseases that cause Haematochezia
Polyposis coli
Diverticulosis
Colonic cancers
Haemorrhoids
Hookworms can cause Innocuos GIT loss T/F
T
List diseases that cause Haematuria
Bladder Cancer
Schistomiasis
Chronic Glomerulonephritis
Ureteral stones/erosion
Renal papillary necrosis
Kidney cancers
Chronic losses from Female Genital
Cervical Erosions/Cervical cancer
Endometriosis
Endometrial cancer
Bleeding endometrial fibroid
Menorrhagia
Diseases that canes Haemoptysis
Tuberculosis
Heart failure
Wagener Granulomatosis
Pulmonary infarctions
Cancer of the Bronchi
Cancer of the lungs
Chronic losses that cause anemia(Purpura)
Thrombocytopenia
Vasculopathy
Von Willebrand disease
Causes of haemathrosis
Coagulant protein deficiencies
Causes of Haematoma
Coagulant protein deficiencies
Examples of chronic losses
Haematemesis (Vomiting of Blood)
Haematochezia (Blood in stool)
Innocuous GIT loss
Haematuria
Chronic losses from female genitalia
Haemoptysis (Chronic losses from lungs)
Purpura (chronic losses to the skin)
Haemathrosis (Losses into the joints)
Haematoma (Losses to the soft tissues)
Types of Anaemia of decreased red cell survival
Intracorpuscular
Extracorpuscular
Types of intracorpuscular defects
Membrane defects
Cytoplasmic defects
Types of membrane defects
Acquired
Inherited
Examples of Inherited Intracorpuscular Membrane Defects
Spherocytosis
Elliptocytosis
Stomatocytosis
Pyropoikilocytosis
Acanthocytosis
Example of an Acquired Intracorpuscular Membrane Defect
Paroxysmal Nocturnal Haemoglobinuria (PNH)
Examples of Cytoplasmic Defects - Enzymopathies
Enzymes of Embden-Myerhoff Pathway
Enzymes of Pentose Phosphate Pathway
Enzymes of Embden-Myerhoff Pathways
Hexose kinase
Pyruvate kinase
Enzymes of Pentose Phosphate pathway
G6PD
Glutathione reductase
Glutathione peroxidase
Gamma-glutamyl-cysteine synthetase
Glutathione synthase
Types of Haemoglobinopathies
Qualitative defects
Quantitative defects
List the Qualitative Haemoglobinopathies
Aggregating haemoglobins - S, C, D and E
Unstable haemoglobins
List the Quantitative Haemoglobinopathies
Thalassaemias- alpha, beta and beta- delta
Other corpuscular defects
- Low ATP concentration
- ATPase deficiency
- Erythropoietic porphyria
- Increased red cell lecithin
Types of extra corpuscular defects
- Immune Mechanisms
- Chemicals/Drugs
- Toxins/Poisons
- Metals
- Waste Metabolic Products
- Infections
- Intravascular Fragmentations
- Heightened Phagocytic activity
Types of immune mechanisms
Warm reacting Antibodies
Cold reacting antibodies
Types of warm reacting antibodies
Isoimmune
Autoimmune
Causes of anemia due to isoimmune warm reacting antibodies
Transfusion
Haemolytic disease of the new born
Causes of anaemia due to autoimmune warm reacting antibodies
SLE
Idiopathic
Causes of decreased red cell survival due to cold reacting antibodies
Cold Agglutinin Syndrome
Paroxysmal cold Haemoglobinuria
Apart from PNH, Acquired Membrane pathology can also be caused by Zeid’s triad
Alcoholic liver disease
Hyperlipidemia
Hemolytic anemias