BCA Critical Care & Intensive Care 3 — Questions and Answers
Question 1: A burn patient is intubated for inhalation injury. Three months later, the patient requires elective surgery. Which anesthetic consideration is most critical?
- Avoid ketamine due to bronchospasm risk
- Avoid succinylcholine due to upregulated acetylcholine receptors (Correct answer)
- Use higher opioid doses due to down-regulated mu receptors
- Avoid propofol due to burn-related lipid abnormalities
Correct answer: Avoid succinylcholine due to upregulated acetylcholine receptors
Burn patients develop upregulation of extrajunctional acetylcholine receptors for weeks to months, making succinylcholine dangerous due to massive potassium release.
Question 2: In a patient with refractory intracranial hypertension despite standard measures, which intervention has level II evidence for ICP reduction?
- Prophylactic hypothermia to 32°C
- Decompressive craniectomy (Correct answer)
- High-dose mannitol infusion
- Prolonged hyperventilation to PaCO2 25 mmHg
Correct answer: Decompressive craniectomy
Decompressive craniectomy is supported by evidence (DECRA, RESCUEicp trials) for refractory ICP reduction when medical management fails.
Question 3: Which acid-base abnormality is expected in a patient with pyloric obstruction and persistent vomiting?
- Metabolic acidosis with low chloride
- Metabolic alkalosis with low chloride (Correct answer)
- Respiratory alkalosis with low potassium
- Mixed metabolic acidosis and respiratory alkalosis
Correct answer: Metabolic alkalosis with low chloride
Loss of gastric HCl through vomiting causes hypochloremic metabolic alkalosis with compensatory renal bicarbonate retention.
Question 4: A critically ill patient on vasopressors develops new ST elevation and troponin rise. Bedside echo shows new wall motion abnormality. Which intervention has the strongest evidence?
- Immediate thrombolytics
- Intra-aortic balloon pump insertion
- Emergent percutaneous coronary intervention (Correct answer)
- High-dose corticosteroids
Correct answer: Emergent percutaneous coronary intervention
Primary PCI is the gold-standard reperfusion strategy for STEMI with cardiogenic shock, associated with superior outcomes over thrombolytics.
Question 5: A patient on mechanical ventilation has auto-PEEP. Which ventilator adjustment will most effectively reduce auto-PEEP?
- Increase tidal volume
- Decrease respiratory rate to lengthen expiratory time (Correct answer)
- Increase PEEP setting
- Increase inspiratory flow rate
Correct answer: Decrease respiratory rate to lengthen expiratory time
Decreasing respiratory rate prolongs expiratory time, allowing more complete exhalation and reducing dynamic hyperinflation (auto-PEEP).
Question 6: In severe traumatic brain injury, which intervention is recommended to reduce secondary injury?
- Maintain PaO2 <80 mmHg to reduce oxidative stress
- Maintain SBP ≥100 mmHg and avoid hypoxia (SpO2 <90%) (Correct answer)
- Target PaCO2 25-30 mmHg routinely
- Restrict IV fluids to <500 mL/day
Correct answer: Maintain SBP ≥100 mmHg and avoid hypoxia (SpO2 <90%)
Current TBI guidelines emphasize avoiding hypotension (SBP <90 mmHg) and hypoxia (SpO2 <90%) as they worsen secondary brain injury.
Question 7: Which electrolyte abnormality is most associated with prolonged QT interval and risk of torsades de pointes in ICU patients?
- Hypernatremia
- Hypokalemia and hypomagnesemia (Correct answer)
- Hypercalcemia
- Hyperphosphatemia
Correct answer: Hypokalemia and hypomagnesemia
Hypokalemia and hypomagnesemia both prolong cardiac repolarization and are the most common electrolyte causes of QT prolongation and torsades in critically ill patients.
BCA Critical Care & Intensive Care 3
A burn patient is intubated for inhalation injury.
Three months later, the patient requires elective surgery.
Which anesthetic consideration is most critical?