Factors influencing development of subcutaneous carbon dioxide emphysema in laparoscopic totally extraperitoneal inguinal hernia repair.

Background: There is a paucity of published data on the incidence of subcutaneous emphysema and the causative factors responsible for its occurrence during laparoscopic procedures. This study was undertaken to evaluate the incidence and factors associated with the occurrence of subcutaneous emphysema in patients undergoing a laparoscopic totally extraperitoneal (TEP) inguinal hernia repair.

Materials And Methods: The prospective study included 100 patients who presented with a primary inguinal hernia and underwent an elective laparoscopic TEP hernia repair from November 2003 to May 2005. Various factors, including age, body mass index (BMI), type of hernia (i.e., unilateral or bilateral, indirect or direct), duration of surgery, and end-tidal carbon-dioxide tension (start and peak), were evaluated. A grading system was evolved to document clinically apparent subcutaneous emphysema immediately and at 6 and 24 hours after the surgical procedure.

Results: A BMI <25, longer operating time (especially >1 hour), and higher end-tidal carbon-dioxide tension (start, peak, and difference) were found to be significantly associated with the development of subcutaneous emphysema. Age and type of hernia -- unilateral versus bilateral, direct versus indirect -- were not found to be statistically significant factors.

Conclusions: The incidence of subcutaneous emphysema in laparoscopic extraperitoneal hernia repairs is high and largely under-reported. Once it is noted, the progression of the surgical emphysema during this type of surgery can have serious complications (e.g., cardiovascular and hemodynamic disturbances) unless timely, appropriate measures are taken. Etiology of subcutaneous emphysema is multifactorial, with no single factor having a prominent association.