ABA Clinical Procedures and Protocols 3 — Questions and Answers
Question 1: A patient with a predicted difficult airway is scheduled for elective surgery. Which preoperative preparation is MOST important before attempting laryngoscopy?
- Premedication with benzodiazepines
- Ensuring a surgeon is available for emergency tracheotomy
- Preoxygenation to maximize apneic oxygenation time (Correct answer)
- Applying topical vasoconstrictor to the nares
Correct answer: Preoxygenation to maximize apneic oxygenation time
Adequate preoxygenation maximizes oxygen reserve, extending safe apneic time and providing the most critical safety margin during a difficult airway attempt.
Question 2: During placement of a central venous catheter via the internal jugular vein, bright red blood aspirates with pulsatile flow. What is the correct immediate management?
- Withdraw the needle and apply firm direct pressure for at least 10 minutes (Correct answer)
- Insert a guidewire and confirm with fluoroscopy
- Aspirate the blood and flush with saline
- Immediately consult vascular surgery for surgical repair
Correct answer: Withdraw the needle and apply firm direct pressure for at least 10 minutes
Inadvertent carotid artery puncture requires immediate needle withdrawal and firm direct compression for at least 10 minutes to achieve hemostasis.
Question 3: A patient undergoing a combined spinal-epidural (CSE) technique for labor analgesia develops sudden fetal bradycardia after intrathecal fentanyl 25 mcg is administered. What is the most likely cause?
- Local anesthetic systemic toxicity
- High spinal block
- Uterine tachysystole secondary to rapid pain relief (Correct answer)
- Placental abruption
Correct answer: Uterine tachysystole secondary to rapid pain relief
Intrathecal opioids cause rapid pain relief, reducing circulating maternal epinephrine, which can result in uterine tachysystole and fetal bradycardia.
Question 4: What is the preferred management of total spinal anesthesia developing shortly after epidural top-up with 20 mL of 0.5% bupivacaine?
- Immediate cesarian delivery
- Vasopressor support, airway management, and left uterine displacement (Correct answer)
- Ephedrine 50 mg IV bolus
- Intralipid 20% infusion
Correct answer: Vasopressor support, airway management, and left uterine displacement
Total spinal requires immediate airway control and ventilatory support, vasopressors for hypotension, and left uterine displacement in obstetric patients.
Question 5: Which test best confirms correct endotracheal tube placement in an apneic patient when end-tidal CO2 waveform is absent due to cardiac arrest?
- Auscultation of bilateral breath sounds
- Chest rise with bag-mask ventilation
- Colorimetric CO2 detector showing color change
- Direct visualization of tube through the vocal cords (Correct answer)
Correct answer: Direct visualization of tube through the vocal cords
In cardiac arrest, colorimetric detectors may give false negatives and auscultation is unreliable; direct visualization of the tube passing through the cords is the most reliable confirmation.
Question 6: A patient develops a tension pneumothorax during positive-pressure ventilation. Where is the correct needle decompression site?
- Second intercostal space, midclavicular line (Correct answer)
- Fourth intercostal space, anterior axillary line
- Second intercostal space, posterior axillary line
- Fifth intercostal space, midaxillary line
Correct answer: Second intercostal space, midclavicular line
Needle decompression is performed at the second intercostal space in the midclavicular line to quickly decompress a tension pneumothorax.
Question 7: During a laparoscopic procedure, the surgeon notes CO2 gas entering the vascular system. What is the hallmark hemodynamic finding of venous gas embolism?
- Sudden increase in end-tidal CO2 followed by a decrease (Correct answer)
- Gradual decrease in blood pressure with reflex tachycardia
- Sudden increase in pulmonary artery pressure with ST elevation
- Paradoxical increase in cardiac output
Correct answer: Sudden increase in end-tidal CO2 followed by a decrease
Venous gas embolism causes an initial transient rise then a precipitous fall in EtCO2 as gas obstructs pulmonary blood flow and reduces CO2 delivery to the lungs.
ABA Clinical Procedures and Protocols 3
A patient with a predicted difficult airway is scheduled for elective surgery.
Which preoperative preparation is MOST important before attempting laryngoscopy?