CSFA General Practice 4 — Questions and Answers
Question 1: A patient develops sudden oxygen desaturation during a right thoracotomy. The anesthesiologist reports loss of breath sounds on the left side. The MOST likely cause is:
- Tension pneumothorax on the right
- Inadvertent endobronchial intubation (Correct answer)
- Pulmonary embolism
- Malignant hyperthermia
Correct answer: Inadvertent endobronchial intubation
Endobronchial (right mainstem) intubation during repositioning or tube migration results in left lung exclusion, causing left-sided breath sound loss and desaturation.
Question 2: The surgical first assistant is retracting during a carotid endarterectomy. Which intraoperative neurological monitoring modality is MOST commonly used to detect cerebral ischemia during carotid clamping?
- Somatosensory evoked potentials (SSEPs)
- Electroencephalography (EEG) (Correct answer)
- Transcranial motor evoked potentials (TcMEPs)
- Bispectral index (BIS) monitoring
Correct answer: Electroencephalography (EEG)
Continuous EEG monitoring during carotid endarterectomy detects cortical ischemia during carotid clamping by showing characteristic frequency slowing or amplitude reduction.
Question 3: During a mastectomy, the surgical first assistant is dissecting along the chest wall. Which muscle forms the posterior boundary of the axilla and must be preserved to maintain shoulder function?
- Pectoralis major
- Serratus anterior (Correct answer)
- Subscapularis
- Latissimus dorsi
Correct answer: Serratus anterior
The serratus anterior muscle protracts and rotates the scapula; injury to its long thoracic nerve innervation causes winged scapula and impaired shoulder abduction.
Question 4: When using a pneumatic tourniquet on an upper extremity, the cuff should be inflated to approximately how much above the patient's systolic blood pressure?
- 25 mmHg above systolic
- 50 mmHg above systolic
- 75 mmHg above systolic (Correct answer)
- 100 mmHg above systolic
Correct answer: 75 mmHg above systolic
For upper extremity tourniquets, inflation pressure is typically set at 50-75 mmHg above systolic blood pressure (commonly 75 mmHg) to ensure arterial occlusion without excessive pressure.
Question 5: During a splenectomy, the surgical first assistant is dividing the splenic ligaments. Injury to which vessel in the splenorenal ligament would cause the MOST immediate life-threatening hemorrhage?
- Left gastric artery
- Splenic artery and vein (Correct answer)
- Left gastroepiploic artery
- Short gastric vessels
Correct answer: Splenic artery and vein
The splenic artery and vein are the largest vessels in the splenorenal ligament; injury causes massive hemorrhage requiring immediate vascular control.
Question 6: Which type of wound healing occurs when a wound is left open to granulate, fill, and re-epithelialize without surgical closure?
- Primary intention (first intention)
- Secondary intention (Correct answer)
- Tertiary intention (delayed primary closure)
- Quaternary healing
Correct answer: Secondary intention
Secondary intention healing occurs when wounds are left open and heal by granulation tissue formation, wound contraction, and epithelialization, typically used for infected or heavily contaminated wounds.
Question 7: The surgical first assistant is performing vessel ligation using a free tie. The preferred knot for ligating a large vessel to prevent slippage is a:
- Square knot with a surgeon's throw first
- Surgeon's knot followed by two square throws (Correct answer)
- Half-hitch only
- Slip knot tightened under tension
Correct answer: Surgeon's knot followed by two square throws
A surgeon's knot (double throw on the first loop) prevents the knot from loosening while the second throw is placed, followed by square throws to secure the ligature on large vessels.
CSFA General Practice 4
A patient develops sudden oxygen desaturation during a right thoracotomy.
The anesthesiologist reports loss of breath sounds on the left side.
The MOST likely cause is: