Abdullah Gürhan Duyan, Muhammed Nezih Koç
Subcutaneous emphysema (SE) is a rare and usually self-limiting complication of laparoscopic totally extraperitoneal (TEP) inguinal hernia repair. We report a 74-year-old man who developed massive SE after a short, technically uncomplicated 32-min TEP repair, despite the absence of major modifiable technical risk factors - working pressure ≤12 mmHg, open (Hasson) entry, single absorbable tack and no peritoneal breach. An abrupt rise in end-tidal carbon dioxide (EtCO 2 ) from a stable baseline (34-36 mmHg) to 60 mmHg was the earliest warning sign and preceded clinical detection. Post-operative computed tomography revealed SE extending to the neck, thorax, abdominal wall, back and both upper and lower extremities, surpassing all categories of the Aghajanzadeh classification. The patient was managed conservatively with manual decompression and an intentionally open trocar site, with complete resolution. This case illustrates an anatomical distribution extending beyond the territories included in conventional SE grading and underscores EtCO 2 monitoring as a valuable early warning tool.