Adhesions after abdominal surgery: a systematic review of the incidence, distribution and severity.

Abdominal adhesions are associated with increased postoperative complications, cost and workload. We performed a systematic review with statistical pooling to estimate the formation rate, distribution and severity of postoperative adhesions in patients undergoing abdominal surgery. A literature search was carried out for all articles reporting on the incidence, distribution and severity of adhesions between January 1990 and July 2011. Twenty-five articles fulfilled the inclusion criteria. The weighted mean formation rate of adhesions after abdominal surgery was 54 % (95 % confidence interval [CI] 40-68 %), and was 66 % (95 % CI 38-94 %) after gastrointestinal surgery, 51 % (95 % CI 40-63 %) after obstetric and gynaecological surgery and 22 % (95 % CI 7-38 %) after urological surgery. The mean overall severity score was 1.11 ± 0.98 according to the Operative Laparoscopy Study Group classification. Laparoscopic surgery reduced the adhesion formation rate by 25 % and decreased the adhesion severity score (laparoscopic; 0.36 ± 0.69 vs. open; 2.14 ± 0.84) for gastrointestinal surgery. Our results demonstrate that the incidence and severity of abdominal adhesions varies between surgical specialties and procedures. An increased awareness of adhesions can help in identifying the underlying mechanisms of adhesion formation and novel therapeutic approaches, while also improving the surgical consent process.