Which monitoring modality is the MOST sensitive detector of venous air embolism during neurosurgical procedures?

• A End-tidal carbon dioxide measurement
• B Transoesophageal echocardiography
• C Precordial Doppler ultrasonography ✓
• D Pulse oximetry

Explanation

Precordial Doppler detects intracardiac air as characteristic mill-wheel type audio changes and can identify entrainment of as little as 0.25 mL/kg of air, making it the most sensitive practical monitor for venous air embolism. Transoesophageal echo is more sensitive in some studies but is invasive and impractical for routine use. End-tidal CO2 falls only after a substantial embolus, and pulse oximetry is a late indicator, so both are far less sensitive than Doppler.

Reference: Morgan and Mikhail's Clinical Anesthesiology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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