Risk of postoperative morbidity in patients having bowel resection for colonic Crohn’s disease

Background: The aim of the present multicenter study was to analyze the incidence and risk factors associated with postoperative morbidity in patients who had colorectal resection for colonic Crohn’s disease. Methods: Consecutive patients undergoing colorectal resection for colonic Crohn’s disease at seven surgical units in 1992–2017 were included. Exclusion criteria were: proctectomy for perianal disease, surgery for cancer, previous colectomies, surgery before 1998. Abdominal colectomy and proctocolectomy were defined as extended resections; all other operations were classified as segmental resections. Postoperative intraabdominal septic complications (IASC) were: anastomotic leaks, peritonitis and abscess. Results: One hundred ninety-nine patients met the inclusion criteria: 116 patients had segmental resections and extended resections were performed in 83 patients. An anastomosis was constructed in 122 patients and an additional stoma was formed in 15 of those cases. Segmental resections were performed significantly more frequently in stricturing or penetrating disease (93% vs. 61%, p < 0.001) and were completed by an anastomosis more often than extended resections (78% vs. 37%, p < 0.001). The overall IASC rate was 17%. On multivariate analysis, formation of an anastomosis (Hazard ratio 2.9; 95% CI 1.1–7.7; p = 0.036) and preoperative hemoglobin level of < 10 g/dl (Hazard ratio 3.1; 95% CI 1.1–9.1; p = 0.034) were associated with an increase of postoperative IASC rate. Preoperative medication did not influence postoperative outcome. Conclusions: Severe preoperative anemia is associated with an increased postoperative morbidity. Resections completed by an anastomosis pose an increased postoperative complication risk in patients with colonic Crohn’s disease as compared to resections without an anastomosis.