CPR APPLICATIONS FOUNDATION · CHAPTER 10 · ABNORMAL
Abnormal Foundations of Hematology
Organize the chapter before drilling into individual CPR concepts.
Supplemental foundation map: this page orients the detailed CPR Applications for Chapter 10. It is not part of the canonical CPR object inventory.
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Normal Foundations
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Treatment Foundations
10.9 · SOURCE CPR FOUNDATION
Concept
Abnormal hematology becomes predictable when every vignette is forced into two axes: production vs destruction and quantitative vs qualitative. Anemia is solved by MCV plus reticulocyte response. Bleeding and clotting are solved by platelet versus coagulation-factor phenotype and PT/PTT localization.
Pattern
Step 1 rarely needs a long differential first. It wants the right bucket: microcytic, normocytic, macrocytic, hemolytic, underproduction, platelet-type bleeding, factor-type bleeding, or hypercoagulability. The named diagnosis comes after the mechanism.
Rule
- Start with the CBC pattern: decide single-line versus multilineage abnormality.
- Use MCV to narrow the anemia differential and an absolute or corrected reticulocyte response to assess production versus loss or destruction; neither measure alone identifies a unique etiology.
- Use bleeding phenotype before PT/PTT: mucosal bleeding suggests platelet/vWF; deep bleeding suggests coagulation factors.
Applications
- Inappropriately low corrected or absolute reticulocyte response in anemia → supports inadequate marrow production; consider timing and context
- Appropriately elevated corrected reticulocytes in anemia → suggests marrow response to blood loss or hemolysis, after sufficient time for compensation
- Mucosal bleeding → platelet or vWF problem
- Deep tissue bleeding → coagulation factor problem
- Tip: Start broad with CBC pattern and bleeding phenotype before jumping to a named disease.
CPR APPLICATIONS · ACTIVE REASONING
Classify anemia and bleeding before naming the disease
Choose a response before checking its mechanism. Every worked solution is also available through the expandable explanation if scripts are blocked. Responses are not saved.
Reveal worked reasoning and transfer
Best answer: Impaired red-cell production. Deficient hemoglobin synthesis or another marrow production limitation can reduce reticulocyte response.
Counterfactual: Which iron studies would help distinguish iron deficiency from other microcytic causes?
Reveal worked reasoning and transfer
Best answer: Secondary hemostasis and coagulation factors. Deep joint and muscle bleeding is characteristic of some coagulation-factor disorders.
Counterfactual: How would epistaxis and petechiae shift attention toward primary hemostasis?
Reveal worked reasoning and transfer
Best answer: Sequestration, peripheral destruction, and marrow failure remain possible. Multilineage cytopenia is not pathognomonic for marrow failure; splenic sequestration is a consideration.
Counterfactual: What additional smear or marrow findings would narrow the mechanism?
Change the mechanism
Scenario explanations without scripts
- Low MCV with low corrected reticulocytes: Consider reduced production; iron status and other tests narrow cause.
- Normal MCV with elevated corrected reticulocytes: Consider loss or hemolysis in the right temporal context.
- Mucosal bleeding despite normal platelets: Consider qualitative platelet dysfunction or von Willebrand disease.
Explain it back: Describe which observation would change the conclusion and why. These are unscored educational exercises, not medical treatment instructions.
How to use this foundation map
- Identify the organizing mechanism.
- Recognize the pattern.
- Restate the rule without looking.
- Test transfer with the applications and question practice.
Pair CPR with the 5P Approach™ when solving cases and questions.