CAA CAA Perioperative Patient Care & Assessment 2 — Questions and Answers
Question 1: A patient undergoing abdominal surgery develops sudden hypotension, tachycardia, and decreased end-tidal CO2 intraoperatively. Which diagnosis should be highest on the differential?
- Malignant hyperthermia
- Pulmonary embolism (Correct answer)
- Anaphylaxis
- Myocardial infarction
Correct answer: Pulmonary embolism
The triad of hypotension, tachycardia, and decreased ETCO2 (reflecting reduced pulmonary blood flow) is classic for pulmonary embolism during surgery.
Question 2: Which intraoperative fluid is considered the most appropriate initial resuscitation fluid for a patient with hemorrhagic shock?
- 5% dextrose in water
- Lactated Ringer's solution (Correct answer)
- Hypotonic saline (0.45%)
- Free water via nasogastric tube
Correct answer: Lactated Ringer's solution
Lactated Ringer's is an isotonic crystalloid that replenishes intravascular volume and is preferred over dextrose solutions for hemorrhagic shock resuscitation.
Question 3: When monitoring a patient in the prone position during spine surgery, which complication specific to this position must the anesthesia assistant continuously monitor for?
- Pneumothorax from central line insertion
- Pressure on the eyes causing ischemic optic neuropathy or corneal abrasion (Correct answer)
- Inadvertent intubation of the right mainstem bronchus
- Catheter-associated urinary tract infection
Correct answer: Pressure on the eyes causing ischemic optic neuropathy or corneal abrasion
Prone positioning increases intraocular pressure and can compress the eyes against headrests, causing corneal abrasion or ischemic optic neuropathy, a cause of postoperative blindness.
Question 4: What is the primary goal of a preoperative beta-blocker continuation strategy in a chronic beta-blocker user presenting for major noncardiac surgery?
- Reduce the risk of bronchospasm under anesthesia
- Prevent perioperative myocardial ischemia and arrhythmias (Correct answer)
- Lower anesthetic MAC requirements
- Increase systemic vascular resistance
Correct answer: Prevent perioperative myocardial ischemia and arrhythmias
Abrupt beta-blocker withdrawal increases catecholamine surges, raising the risk of perioperative myocardial ischemia and dangerous arrhythmias in chronic users.
Question 5: A post-surgical patient in the PACU complains of severe nausea and vomits twice. She received fentanyl and nitrous oxide during her 3-hour procedure. What is the MOST likely contributing factor?
- Malignant hyperthermia
- Postoperative nausea and vomiting (PONV) secondary to opioid and N2O exposure (Correct answer)
- Hypoglycemia from prolonged fasting
- Residual neuromuscular blockade
Correct answer: Postoperative nausea and vomiting (PONV) secondary to opioid and N2O exposure
Opioids and nitrous oxide are well-established independent risk factors for PONV; the combination significantly increases incidence, especially in female patients after longer procedures.
Question 6: When performing a preoperative review of a pediatric patient's chart, which weight-based calculation is used to estimate the appropriate endotracheal tube (ETT) size for a child older than 2 years?
- (Age in years / 4) + 4 (Correct answer)
- (Weight in kg / 10) + 2
- Age in years + 4
- (Height in cm / 30) – 2
Correct answer: (Age in years / 4) + 4
The formula (Age/4) + 4 estimates uncuffed ETT internal diameter in millimeters for children older than 2 years and is the most widely cited pediatric guideline.
Question 7: Intraoperatively, the surgeon requests controlled hypotension to reduce blood loss during a total hip arthroplasty. What is the general target mean arterial pressure (MAP) during deliberate hypotension in a healthy adult?
- 30–40 mmHg
- 50–65 mmHg (Correct answer)
- 70–80 mmHg
- 90–100 mmHg
Correct answer: 50–65 mmHg
A MAP of 50–65 mmHg is typically targeted during deliberate hypotension in healthy adults, balancing reduced surgical bleeding against adequate perfusion to vital organs.
CAA CAA Perioperative Patient Care & Assessment 2
A patient undergoing abdominal surgery develops sudden hypotension, tachycardia, and decreased end-tidal CO2 intraoperatively.
Which diagnosis should be highest on the differential?