Simulated case set: Postoperative cardiothoracic reasoning
Educational work by a pre-medical student — not medical advice. Not a clinical protocol, prescription, or patient handout, and not for patient care. See DISCLAIMER.
Entirely synthetic independent premedical study material. Revised 27 October 2026. The author confirmed that scenarios are independent of real encounters/charts. This reconstruction preserves the earlier topic coverage while withdrawing unsupported medication doses, device adjustments and automatic escalation thresholds. Earlier versions remain in Git history.
How to use these worked examples
Read the paired patient examples and integrated clinical narratives linked under each scenario. The examples explain interpretation and conditional care decisions; no student answers or scoring are required. See the procedure-organized CTICU casebook and source guide.
Scenario 1: CABG with vasoplegia, hypothermia and bleeding
Paired synthetic application examples. Integrated workup and test reasoning.
Synthetic vignette: A fictional bypass recipient has hypotension, a rising lactate trend, reduced calculated vascular resistance and drain output.
Worked example interpretation
Check how resistance was calculated and whether bleeding, pump dysfunction and tone abnormalities overlap. Vasopressors do not replace correction of an anatomic or bleeding cause; do not infer vasodilation from low temperature alone. The linked paired example and integrated narrative explain the patient-specific context, investigation purposes and reassessment.
Interpretation boundary: A preserved EF does not exclude important low-output physiology, and hypothermia should not be assumed to cause vasodilation.
Scenario 2: VA-ECMO with rising lactate
Paired synthetic application examples. Integrated workup and test reasoning.
Synthetic vignette: A fictional myocarditis patient on VA-ECMO has rising lactate and concern about hemolysis, LV distension or circuit dysfunction.
Worked example interpretation
Evaluate LV loading, blood trauma and circuit performance separately; apparent circuit flow does not establish effective tissue delivery. An escalation in vasoactive drugs or circuit flow is not a universal response; the ECMO team evaluates competing effects. The linked paired example and integrated narrative explain the patient-specific context, investigation purposes and reassessment.
Interpretation boundary: A transmembrane gradient alone is not an oxygenator-change rule; interpretation belongs to the ECMO team.
Scenario 3: LVAD with RV dysfunction
Paired synthetic application examples. Integrated workup and test reasoning.
Synthetic vignette: A fictional LVAD recipient has rising venous pressure, falling pulsatility and worsening renal function.
Worked example interpretation
Compare RV, rhythm and loading explanations using imaging and device context; a congestion label does not prove fluid responsiveness. Fluid, diuretic and inotrope discussions require different supporting findings and device-team review. The linked paired example and integrated narrative explain the patient-specific context, investigation purposes and reassessment.
Interpretation boundary: Device alarms and displayed flow do not establish a unique diagnosis or universal speed adjustment.
Scenario 4: ARDS after supination
Paired synthetic application examples. Integrated workup and test reasoning.
Synthetic vignette: A fictional adult with ARDS has worsening oxygenation and carbon dioxide retention after supination.
Worked example interpretation
Recheck airway mechanics, comparable gases and positional effects before attributing deterioration to loss of recruitment alone. A mode switch, paralytic or sedative is not guaranteed to reduce lung stress; ECMO assessment is a separate specialist question. The linked paired example and integrated narrative explain the patient-specific context, investigation purposes and reassessment.
Interpretation boundary: A mode switch alone does not cap injurious lung stress. No universal pH or driving-pressure trigger for ECMO is prescribed.
Scenario 5: Aortic repair with new pain and oliguria
Paired synthetic application examples. Integrated workup and test reasoning.
Synthetic vignette: A fictional aortic-surgery patient has new back pain, hypertension and deteriorating urine output.
Worked example interpretation
New symptoms after repair require urgent anatomic/perfusion reassessment; a filling-pressure target cannot rule out malperfusion. Analgesia may be needed but should not become a substitute for evaluation of the underlying complication. The linked paired example and integrated narrative explain the patient-specific context, investigation purposes and reassessment.
Interpretation boundary: This is a prompt for urgent expert evaluation, not a sequence of fluids followed by imaging only if a numerical target fails.
Scenario 6: Early lung-graft dysfunction
Paired synthetic application examples. Integrated workup and test reasoning.
Synthetic vignette: A fictional transplant recipient has low compliance and worsening gas exchange soon after surgery.
Worked example interpretation
Organize the differential before labeling PGD; ventilation measurements do not independently establish recruitability. No PEEP change, immune regimen or ECMO threshold is derived from the limited data. The linked paired example and integrated narrative explain the patient-specific context, investigation purposes and reassessment.
Interpretation boundary: No graft diagnosis, PEEP range or ECMO threshold follows from this short vignette alone.
Scenario 7: Abdominal sepsis with refractory shock
Paired synthetic application examples. Integrated workup and test reasoning.
Synthetic vignette: A fictional adult after bowel surgery remains shocked with oliguria and venous congestion.
Worked example interpretation
Assess infection control, perfusion and kidney complications separately; severe AKI alone is not an automatic accelerated-dialysis mandate. Antimicrobials, fluid/vasoactive treatment and renal support have separate indications and exposure considerations. The linked paired example and integrated narrative explain the patient-specific context, investigation purposes and reassessment.
Interpretation boundary: Laboratory values and positive balance do not alone establish a dialysis indication or an ultrafiltration rate.
Scenario 8: SAH with cardiac dysfunction
Paired synthetic application examples. Integrated workup and test reasoning.
Synthetic vignette: A fictional aneurysmal-SAH patient has reduced cardiac function and uncertain cerebral perfusion.
Worked example interpretation
Verify MAP/ICP measurement conditions and distinguish vasospasm from the clinical syndrome of delayed ischemia. A preselected pressor target or sodium range is not justified by the label SAH alone. The linked paired example and integrated narrative explain the patient-specific context, investigation purposes and reassessment.
Interpretation boundary: A preselected MAP or sodium range is not a validated plan for every SAH patient.