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Treatment Foundations of Infectious Disease

CPR APPLICATIONS FOUNDATION · CHAPTER 12 · TREATMENT

Treatment Foundations of Infectious Disease

Organize the chapter before drilling into individual CPR concepts.

Supplemental foundation map: this page orients the detailed CPR Applications for Chapter 12. It is not part of the canonical CPR object inventory.

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12.25 · SOURCE CPR FOUNDATION

Concept

Infectious disease treatment matches syndrome severity, likely organism, host risk, site penetration, resistance risk, and need for source control. Severe syndromes require timely empiric therapy. Stable situations may allow cultures before antibiotics and narrower targeting after microbiology returns.

Pattern

Step 1 asks for the best next step, empiric therapy logic, diagnostic confirmation, prevention, or complication avoidance. Sepsis, meningitis, neutropenic fever, and unstable infection require urgent action. Endocarditis, abscess, device infection, and obstruction require attention to cultures or source control when appropriate.

Rule

  1. Treat severe infection urgently. Stabilization and empiric coverage may precede final diagnosis.
  2. Narrow when data return. Culture and susceptibility should refine therapy when available.
  3. Address source control. Abscess, hardware, obstruction, and necrotic tissue can defeat antibiotics alone.

Applications

  • Sepsis → cultures broad empiric therapy source control
  • Suspected bacterial meningitis → obtain blood cultures promptly if feasible, but do not delay empiric antibiotics for imaging or lumbar puncture when those would postpone treatment
  • Stable endocarditis → blood cultures before antibiotics
  • Abscess → incision and drainage
  • Device infection → remove infected hardware when needed
  • C. difficile → stop inciting antibiotic when possible and treat syndrome
  • Tip: Right antibiotic can still fail without source control

CPR APPLICATIONS · ACTIVE REASONING

Prioritize urgent care and source control

Make a prediction first. Each worked answer is available without JavaScript. These exercises do not save or send responses.

Decision 1: Suspected bacterial meningitis requires lumbar puncture but imaging would delay it. What must not be delayed?

Worked reasoning and transfer

Best answer: Empiric antimicrobials after prompt blood cultures when feasible. Imaging or LP should not postpone urgent therapy.

Transfer: How does hemodynamic instability affect priority?

Decision 2: An unstable septic patient has a likely bacterial source. What is the urgent sequence?

Worked reasoning and transfer

Best answer: Resuscitation, timely empiric therapy and source assessment. Cultures should be obtained rapidly when feasible without materially delaying antibiotics.

Transfer: How does culture return change coverage?

Decision 3: A drainable infected collection persists. What intervention complements antimicrobials?

Worked reasoning and transfer

Best answer: Source control. Abscess drainage can be essential when indicated.

Transfer: What if the nidus is infected hardware?

Explain it back: Write a causal chain for one decision, then identify which piece of evidence would change the answer.

Unscored teaching examples; not validated assessment items or patient-specific advice.

How to use this foundation map

  1. Identify the organizing mechanism.
  2. Recognize the pattern.
  3. Restate the rule without looking.
  4. Test transfer with applications and question practice.

Pair CPR with the 5P Approach™ when solving cases and questions.

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