Smoking impairs rectal mucosal bloodflow--a pilot study: possible implications for transanal advancement flap repair

Transanal advancement flap repair has been advocated as the treatment of choice for trans-sphincteric perianal fistulas, because it enables the healing of almost all fistulas without sphincter damage and consequent continence disturbance. After initial promising reports, recently less favorable results have been reported. It remains unclear why there is such a large variety in the reported healing rates. Recently, it has been suggested that impaired wound healing caused by a diminished rectal mucosal perfusion in patients who smoke may lead to the breakdown of the advancement flap in patients undergoing flap repair for perianal fistulas. This study was designed to investigate the difference in blood flow in rectal mucosa between patients who smoke and those who do not smoke. Furthermore, we assessed the impact of the creation of a mucosa advancement flap and the difference in blood flow in the flap between smoking and nonsmoking patients. Between July 2001 and July 2002, 23 consecutive patients (19 males; median age, 46 (range, 26-69) years) with a perianal fistula of cryptoglandular origin underwent surgery for a perianal fistula. Among them were 13 patients who smoked cigarettes. All patients underwent intraoperative laser Doppler flowmetry. Median blood flow before transanal advancement flap repair was 35 (range, 8-70) volts in patients who did not smoke. In patients who smoked the median blood flow before transanal advancement flap repair was 18 (range, 7-35) volts. Blood flow was significantly lower in patients who smoked (P = 0.018; Mann-Whitney). In conclusion, it seems likely that impaired wound healing caused by a diminished rectal mucosal perfusion is a contributing factor in the breakdown of advancement flaps in patients who smoke cigarettes.