skip to main content

Laparoscopic Surgical Emphysema — FRCA Final MCQ

Instant feedback + full explanation. One question, done properly.

ModerateGeneral AnaesthesiaLaparoscopic Surgical EmphysemaFRCA Final

A 30-year-old woman undergoes laparoscopic surgery under general anaesthesia with carbon dioxide pneumoperitoneum. During insufflation, swelling and palpable crepitus develop over her chest and neck, and her end-tidal carbon dioxide rises from 4.5 to 7.2 kPa despite unchanged ventilation. Oxygen saturation and haemodynamic variables remain stable, air entry is equal bilaterally, and peak airway pressure is unchanged. Which explanation best accounts for these findings?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: A — Extraperitoneal carbon dioxide tracking along tissue planes with systemic absorption

Explanation lettering: E = shown as B · B = shown as C · C = shown as E

A is correct. Carbon dioxide can escape around a laparoscopic port or enter an extraperitoneal plane, then dissect through the highly compliant subcutaneous tissues to the chest and neck. Absorption across the large subcutaneous surface produces the marked rise in end-tidal carbon dioxide. Stable oxygenation, equal air entry and unchanged airway pressure argue against a clinically significant capnothorax or tension pneumothorax; these usually impair ventilation and may cause hypoxaemia or haemodynamic compromise. Endobronchial intubation would cause unilateral reduction in air entry and altered respiratory mechanics. Oesophageal perforation can produce mediastinal and subcutaneous gas but does not explain the close relationship to carbon-dioxide insufflation and rapid hypercapnia. A concomitant capnothorax should nevertheless be actively excluded.

Reference: Ito K et al. Subcutaneous emphysema associated with laparoscopic or robotic abdominal surgery: a retrospective single-center study. Surgical Endoscopy. 2024;38:1969-1975. https://pubmed.ncbi.nlm.nih.gov/38379005/