Anemia: Difference between revisions
 
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==Background==
==Background==
*Anemia is a condition of decreased hemoglobin (Hb) concentration compared to age-matched and gender-matched controls.
**Males: Hb < 13 g/dL
**Non-Pregnant Females: Hb < 12 g/dL
**Pregnant-Females: Hb < 11g/dL
**Children: Hb <  <11-12 g/dL (depends on age)
*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
 
**4 mechanisms:
===Pathophysiology===
**#Loss of RBCs by hemorrhage (e.g. GI bleed)
4 mechanisms:
**#Increased destruction (SCD, hemolytic anemia)
*Loss of RBCs by hemorrhage (e.g. [[GI bleed]], [[trauma]])
**#Impaired production (iron/folate/B12 deficiency, aplastic/myelodysplastic anemia)
*Increased destruction ([[sickle cell disease|SCD]], [[hemolytic anemia]])
**#Dilutional (rapid IVF infusion)
*Impaired production (iron deficiency, [[folate deficiency]], [[B12 deficiency]], [[aplastic anemia]]/[[myelodysplastic syndrome]])
*Dilutional (rapid [[IVF]] infusion)


==Clinical Features==
==Clinical Features==
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{{Anemia DDX}}
{{Anemia DDX}}


==Diagnosis==
==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 [[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===
*Assess for any signs of bleeding or trauma before considering other causes of chronic anemia.
 
[[File:Anemia.png|thumb|Algorithm for the Evaluation of Anemia]]
[[File:Anemia.png|thumb|Algorithm for the Evaluation of Anemia]]
===Microcytic Anemia (<81 fL)===
 
*RDW high
===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 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]]


==Treatment==
==Management==
*[[Transfusions]]
*[[Transfusions]]
**Consider if pt is symptomatic, hemodynamically unstable, hypoxic, or acidotic
**Consider if patient is symptomatic, hemodynamically unstable, hypoxic, or acidotic
**Most pts w/ Hb <6 will benefit from transfusion; most pts w/ Hb >10 will not
**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
**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 supplementation|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''
 
===Admission===
*Evidence or potential for ongoing blood loss
*Signs of end-organ dysfunction (altered mental status, cardiac ischemia, etc.)
 
===Discharge===
*Most stable patients can be discharged w/ outpatient follow-up if they are asymptomatic or only mildly symptomatic following an incidental finding of anemia.


==See Also==
==See Also==
*[[Transfusions]]
*[[Transfusions]]
*[[Myelophthistic anemia]]
*[[Myelophthisic Anemia]]
*[[Microangiopathic Hemolytic Anemia (MAHA)]]
*[[Microangiopathic Hemolytic Anemia (MAHA)]]
==External Links==
*[http://ddxof.com/anemia/ DDxOf: Differential Diagnosis of Anemia]
*[http://www.emdocs.net/anemia-in-the-ed-setting-pearls-and-pitfalls/ emDOCS - Anemia in the ED Setting: Pearls and Pitfalls]


==References==
==References==

Latest revision as of 21:02, 22 August 2021

Background

  • Anemia is a condition of decreased hemoglobin (Hb) concentration compared to age-matched and gender-matched controls.
    • Males: Hb < 13 g/dL
    • Non-Pregnant Females: Hb < 12 g/dL
    • Pregnant-Females: Hb < 11g/dL
    • Children: Hb < <11-12 g/dL (depends on age)
  • Affects 1/3 of the world's population
  • Most common causes are uterine and GI bleeding

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

Admission

  • Evidence or potential for ongoing blood loss
  • Signs of end-organ dysfunction (altered mental status, cardiac ischemia, etc.)

Discharge

  • Most stable patients can be discharged w/ outpatient follow-up if they are asymptomatic or only mildly symptomatic following an incidental finding 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
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