Anemia: Difference between revisions

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==Background==
==Background==
*Affects 1/3 of the world's population
*Affects 1/3 of the world's population
*Most common causes are uterine and GI bleeding
*Most common causes are [[vaginal Bleed Non-Pregnant|uterine]] and [[GI bleeding]]


===Pathophysiology===
===Pathophysiology===
4 mechanisms:
4 mechanisms:
#Loss of RBCs by hemorrhage (e.g. GI bleed)
*Loss of RBCs by hemorrhage (e.g. [[GI bleed]], [[trauma]])
#Increased destruction (SCD, hemolytic anemia)
*Increased destruction ([[sickle cell disease|SCD]], [[hemolytic anemia]])
#Impaired production (iron deficiency, [[folate deficiency]], [[B12 deficiency]], [[aplastic anemia]]/[[myelodysplastic syndrome]])
*Impaired production (iron deficiency, [[folate deficiency]], [[B12 deficiency]], [[aplastic anemia]]/[[myelodysplastic syndrome]])
#Dilutional (rapid IVF infusion)
*Dilutional (rapid [[IVF]] infusion)


==Clinical Features==
==Clinical Features==
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==Evaluation==
==Evaluation==
''Severe anemia is defined as a hemoglobin level of 5 to 7 g/dL with symptoms of hypoperfusion including lactic acidosis, base deficit, shock, hemodynamic instability, or coronary ischemia<ref> Posluszny JA Jr, Napolitano LM. How do we treat life-threatening anemia in a Jehovah's Witness patient? Transfusion. 2014;54(12):3026-3034</ref>''
''Severe anemia is defined as a hemoglobin level of 5 to 7 g/dL with symptoms of hypoperfusion including [[lactic acidosis]], base deficit, shock, hemodynamic instability, or [[myocardial ischemia|coronary]] ischemia<ref> Posluszny JA Jr, Napolitano LM. How do we treat life-threatening anemia in a Jehovah's Witness patient? Transfusion. 2014;54(12):3026-3034</ref>''


===Acute Anemia===
===Acute Anemia===
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*RDW high → evaluate Ferritin, which is a measurement of iron storage
*RDW high → evaluate Ferritin, which is a measurement of iron storage
**Ferritin low: Iron deficiency anemia
**Ferritin low: Iron deficiency anemia
**Ferritin normal: Anemia chronic disease or sideroblastic anemia (e.g. lead poisoning)
**Ferritin normal: Anemia chronic disease or sideroblastic anemia (e.g. [[lead poisoning]])
*RDW normal
*RDW normal
**RBC count low: Anemia chronic disease, hypothyroidism, Vitamin C deficiency
**RBC count low: Anemia chronic disease, [[hypothyroidism]], [[Vitamin C deficiency]]
**RBC count nl or high: Thalassemia
**RBC count normal or high: [[Thalassemia]]


====Normocytic Anemia (81-100 fL)====
====Normocytic Anemia (81-100 fL)====
*Retic count normal
*Retic count normal
**RDW normal: Anemia chronic disease, anemia of renal insufficiency
**RDW normal: Anemia chronic disease, anemia of renal insufficiency
**RDW high: Iron, Vit B12, or folate deficiency
**RDW high: Iron, Vit [[b12 deficiency|B12]], or [[folate deficiency]]
*Retic count high
*Retic count high
**Coombs Positive: Autoimmune cause
**Coombs Positive: Autoimmune cause
**Coombs negative: G6PD, SCD, spherocytosis, microangiopathic hemolysis
**Coombs negative: [[G6PD]], [[sickle cell disease|SCD]], spherocytosis, [[microangiopathic hemolytic anemia|microangiopathic hemolysis]]


====Macrocytic Anemia (MCV>100 fL)====
====Macrocytic Anemia (MCV>100 fL)====
*RDW high: Vit B12 or folate deficiency
*RDW high: [[B12 deficiency|Vit B12]] or [[folate deficiency]]
*RDW normal: ETOH abuse, liver disease, hypothyroidism, drug induced, myelodysplasia
*RDW normal: [[ETOH abuse]], [[hepatic failure|liver disease]], [[hypothyroidism]], drug induced, [[myelodysplastic syndrome|myelodysplasia]]


==Management==
==Management==
[[Transfusions]]
*[[Transfusions]]
*Consider if patient is symptomatic, hemodynamically unstable, hypoxic, or acidotic
**Consider if patient is symptomatic, hemodynamically unstable, hypoxic, or acidotic
*Using a restrictive transfusion strategy (transfusing <6-8) has found to be beneficial, as liberal transfusion strategy (transfusing <10) not showing any benefit and has shown harm
**Using a restrictive transfusion strategy (transfusing <6-8) has found to be beneficial, as liberal transfusion strategy (transfusing <10) not showing any benefit and has shown harm
**GI bleeds using restrictve transfusion strategy saw a decreased mortality and rebleed rate
***GI bleeds using restrictive transfusion strategy saw a decreased mortality and rebleed rate
*Always draw labs necessary for diagnosis prior to transfusing
**Always draw labs necessary for diagnosis prior to transfusing
*1 unit PRBCs should raise the Hgb by 1gm/dL
**1 unit PRBCs should raise the Hgb by 1gm/dL
Iron-deficiency anemia
*[[iron supplementation|Iron-deficiency anemia]]
*PO: Ferrous sulfate 325mg (65mg elemental iron) with Vitamin C (to aid in absorption)
**PO: Ferrous sulfate 325mg (65mg elemental iron) with Vitamin C (to aid in absorption)
*IV: Ferrous Sucrose 300mg in 250mL NS over 2hrs
**IV: Ferrous Sucrose 300mg in 250mL NS over 2hrs


==Disposition==
==Disposition==
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==See Also==
==See Also==
*[[Transfusions]]
*[[Transfusions]]
*[[Myelophthistic anemia]]
*[[Myelophthisic anemia]]
*[[Microangiopathic Hemolytic Anemia (MAHA)]]
*[[Microangiopathic Hemolytic Anemia (MAHA)]]



Revision as of 23:32, 30 September 2019

Background

Pathophysiology

4 mechanisms:

Clinical Features

General Anemia Symptoms

Differential Diagnosis

Anemia

RBC Loss

RBC consumption (Destruction/hemolytic)

Impaired Production (Hypochromic/microcytic)

  • Iron deficiency
  • Anemia of chronic disease
  • Thalassemia
  • Sideroblastic anemia

Aplastic/myelodysplastic (normocytic)

  • Marrow failure
  • Chemicals (e.g. ETOH)
  • Radiation
  • Infection (HIV, parvo)

Megaloblastic (macrocytic)

Evaluation

Severe anemia is defined as a hemoglobin level of 5 to 7 g/dL with symptoms of hypoperfusion including lactic acidosis, base deficit, shock, hemodynamic instability, or coronary ischemia[1]

Acute Anemia

  • Assess for any signs of bleeding or trauma before considering other causes of chronic anemia.
Algorithm for the Evaluation of Anemia

Chronic Anemia

  • CBC for evaluation, look at MCV
    • Microcytic: Iron Levels, Reticulocyte Count, Ferritin, TIBC
    • Macrocytic: Folate Level, B12 Level, Reticulocyte Count

Microcytic Anemia (<81 fL)

  • RDW high → evaluate Ferritin, which is a measurement of iron storage
    • Ferritin low: Iron deficiency anemia
    • Ferritin normal: Anemia chronic disease or sideroblastic anemia (e.g. lead poisoning)
  • RDW normal

Normocytic Anemia (81-100 fL)

Macrocytic Anemia (MCV>100 fL)

Management

  • Transfusions
    • Consider if patient is symptomatic, hemodynamically unstable, hypoxic, or acidotic
    • Using a restrictive transfusion strategy (transfusing <6-8) has found to be beneficial, as liberal transfusion strategy (transfusing <10) not showing any benefit and has shown harm
      • GI bleeds using restrictive transfusion strategy saw a decreased mortality and rebleed rate
    • Always draw labs necessary for diagnosis prior to transfusing
    • 1 unit PRBCs should raise the Hgb by 1gm/dL
  • Iron-deficiency anemia
    • PO: Ferrous sulfate 325mg (65mg elemental iron) with Vitamin C (to aid in absorption)
    • IV: Ferrous Sucrose 300mg in 250mL NS over 2hrs

Disposition

  • Depends on underlying cause of anemia

See Also

External Links

References

  1. Posluszny JA Jr, Napolitano LM. How do we treat life-threatening anemia in a Jehovah's Witness patient? Transfusion. 2014;54(12):3026-3034