Barotrauma during mechanical ventilation in theatre is MOST closely related to which ventilator parameter?

• A Peak inspiratory pressure (PIP) exceeding 30 cmH2O
• B Mean airway pressure sustained above 15 cmH2O
• C Positive end-expiratory pressure (PEEP) exceeding 10 cmH2O
• D Plateau pressure (Pplat) exceeding 30 cmH2O reflecting true alveolar overdistension ✓

Explanation

Barotrauma (pneumothorax, pneumomediastinum, subcutaneous emphysema) is caused by alveolar overdistension, which is reflected by plateau pressure, not peak inspiratory pressure. PIP includes the pressure drop across the airways and ETT, which does not reach alveoli. Plateau pressure is measured during an end-inspiratory pause (zero flow), eliminating airway resistance component, and thus accurately represents true alveolar pressure. A Pplat >30 cmH2O is the lung-protective threshold in ARDS protocols (ARDSnet), above which barotrauma and ventilator-induced lung injury risk increases significantly.

Reference: Morgan & Mikhail's Clinical Anesthesiology, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.