CPR APPLICATIONS FOUNDATION · CHAPTER 2 · ABNORMAL
Abnormal Foundations of Pathology
Use a chapter-level CPR map to organize the recurring ways normal function breaks and how those deviations present.
Supplemental foundation map: this page orients the detailed CPR Applications for Chapter 2. It is not part of the canonical CPR object inventory.
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Normal Foundations
Abnormal Foundations · You are here
Treatment Foundations
2.9 · SOURCE CPR FOUNDATION
Concept
Abnormal pathology begins when adaptive capacity is exceeded and cells shift from compensation to injury. Step 1 focuses on the point where dysfunction becomes irreversible because that transition predicts morphology, inflammation, and clinical consequences. Most injury pathways converge on a limited set of outcomes: reversible injury, necrosis, apoptosis, inflammation, repair, fibrosis, or neoplasia.
Pattern
Step 1 often presents abnormal pathology as a cell fate question. Hypoxia, toxins, infection, immune injury, and neoplasia may begin differently but funnel into predictable injury patterns. The key is to identify the insult, decide whether the injury is reversible or irreversible, and then predict the tissue response.
Rule
- Anchor to the insult first: ischemia, infection, immune injury, toxins, and neoplasia each produce characteristic pathology patterns.
- Decide reversible versus irreversible: reversible injury suggests swelling and dysfunction; irreversible injury suggests necrosis, apoptosis, or permanent tissue loss.
- Use the cell death pattern to predict inflammation: necrosis is inflammatory; apoptosis is controlled and usually minimally inflammatory.
Applications
- Myocardial infarction → typically coagulative necrosis after irreversible ischemic injury (unlike the liquefactive pattern classically seen in cerebral infarction)
- Appendicitis → neutrophilic acute inflammation
- Tuberculosis → granulomatous containment
- Pressure ulcer → secondary intention healing
- Colon adenocarcinoma → invasion and metastasis
Active practice: injury pattern
Predict, then expand the explanation.
Which tissue response follows a brief, recoverable reduction in oxygen delivery?
Reversible cell swelling
Correct. Temporary ATP depletion impairs ion pumps and can increase cell water content.
Invariably permanent injury
Incorrect. The response depends on the severity and duration of the insult.
How do established cardiac and brain infarcts typically differ?
Cardiac coagulative pattern and brain liquefactive pattern
Correct. Brain tissue is an important exception to the common solid-organ pattern.
Both always have identical morphology
Incorrect. Tissue context changes the expected morphology.
Transfer
What does contained cellular fragmentation with little inflammation suggest?
Reveal
Apoptosis, which differs from uncontrolled membrane disruption.
How to use this foundation map
- Read the Concept and identify the organizing mechanism.
- Use the Pattern to recognize how the mechanism tends to appear in Step 1-style reasoning.
- Restate the Rule without looking, then test whether each application follows from it.
- Move to the adjacent foundation layer or use question practice to test transfer.
When applying the organized knowledge to a case or question, pair CPR with the 5P Approach™.
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