Respiratory and Thoracic Anesthesia Flashcards

Bronchospasm during thoracic surgery is LEAST likely to respond to which intervention?

Answer: IV rocuronium

Neuromuscular blocking agents have no bronchodilatory effect; bronchospasm requires agents that relax airway smooth muscle via adrenergic or anti-cholinergic mechanisms.

During video-assisted thoracoscopic surgery (VATS), inadequate lung collapse despite a correctly positioned DLT is most efficiently addressed by:

Answer: Insufflating CO2 into the pleural space at low pressure

Low-pressure CO2 insufflation (up to 8 mmHg) into the pleural cavity rapidly collapses the operative lung and improves surgical visualization when passive collapse is incomplete.

A bronchial blocker is preferred over a double-lumen tube in which clinical scenario?

Answer: Patient with a difficult airway already intubated with a size 7.5 single-lumen tube

A bronchial blocker can be advanced through an existing single-lumen ETT under fiberoptic guidance, avoiding the need to exchange to a larger tube in a difficult airway.

The phenomenon of 'auto-PEEP' during one-lung ventilation is most commonly caused by:

Answer: Inadequate expiratory time leading to air trapping

Auto-PEEP (intrinsic PEEP) develops when the next breath begins before full exhalation, trapping gas and increasing end-expiratory lung volume, particularly in COPD patients.

Which parameter best predicts postoperative pulmonary complications after lung resection?

Answer: Diffusing capacity for carbon monoxide (DLCO)

DLCO reflects gas exchange surface area and pulmonary vascular reserve; predicted postoperative DLCO <40% correlates strongly with postoperative morbidity and mortality.

A patient with a large right-sided pleural effusion requires thoracentesis under general anesthesia. During drainage, she suddenly becomes hypotensive and dyspneic. The most likely diagnosis is:

Answer: Re-expansion pulmonary edema

Rapid drainage of large pleural effusions can cause re-expansion pulmonary edema as chronically collapsed lung tissue rapidly fills with fluid, releasing inflammatory mediators.

In thoracic epidural analgesia for open thoracotomy, the optimal dermatomal level of catheter insertion is:

Answer: T4-T8

Thoracic epidural catheters placed at T4-T8 provide analgesia centered on the thoracotomy incision, optimizing pain control and preserving respiratory function.