Int J Colorectal Dis (2009) 24:789–795 Table 1 Description of operated population and univariate analysis Population description and univariate analysis Factor BMI (kg/m2)a <25 25-30 >30 Age (years)b Gender (M/F) Smokerc Use of steroidsc Use of Anti-hypertensive medicationc Use of statinesc ASA-scorec History of vascular diseasec Cardiac comorbidityc Pulmonary comorbidityc Diabetes mellitusc Blood transfusionc Mechanical bowel preparationd Neoadjuvant radiotherapy Anastomotic configurationc Surgical indication Approach Surgeon vs. assistant Stapled vs. hand-suturedc Urgent vs. Elective Prophylactic Yes drainage No Time of surgerye During-hours After-hours Duration of operation (minutes)b Time under anesthesia (minutes) b Anastomotic leakage 33 (9%) 13 (6%) 15 (20%) 61 (22 – 84) 32(9%)/ 32 (9%) Yes: 16 (9%) No: 44 (8%) Yes: 13 (12%) No: 51 (8%) Yes: 7 (5%) No: 55 (9%) Yes: 6 (9%) No: 56 (8%) I: 13 (20%) II: 27 (42%) III: 20 (31%) IV: 1 (2%) V: 0 (0%) Yes: 11 (9%) No: 51 (8%) Yes: 13 (9%) No: 49 (8%) Yes: 8 (9%) No: 49 (8%) Yes: 6 (9%) No: 57 (9%) Yes: 14 (13%) No: 48 (8%) Yes: 37 (8%) No: 16 (10%) Yes: 1 (8%) No: 63 (9%) E-E 7 (12%) E-S 2 (2%) S-E 21 (11%) S-S 33 (9%) Cancer: 37 (9%) IBD: 6 (5%) Diverticular disease: 3 (5%) Other: 18 (12%) Laparotomy: 59 (9%) Laparoscopy: 5 (5%) Surgeon 13 (10%) Assistant 51 (8%) Stapled 5 (8%) Sutured 57 (9%) Urgent: 19 (12%) Elective: 45 (8%) 21 (15%) 43 (7%) 49 (8%) 15 (14%) 163 (70 – 365) 226 (110 – 426) No anastomotic leakage 343 (91%) 217 (94%) 62 (81%) 60 (18 – 99) 346 (91%)/ 329 (91%) Yes: 163 (91%) No: 485 (92%) Yes: 96 (88%) No: 569 (92%) Yes: 137 (95%) No: 532 (91%) Yes: 63 (91%) No: 608 (92%) I: 162 (24%) II: 303 (45%) III: 125 (19%) IV: 20 (3%) V: 1 (0,1%) Yes: 106 (91%) No: 564 (92%) Yes: 134 (91%) No: 539 (92%) Yes: 85 (91%) No: 563 (92%) Yes: 60 (91%) No: 606 (91%) Yes: 91 (87%) No: 550 (92%) Yes: 436 (92%) No: 142 (90%) Yes: 11 (92%) No: 664 (91%) E-E 52 (88%) E-S 90 (98%) S-E 170 (89%) S-S 345 (91) Diverticular disease: 53 (95%) IBD: 109 (95%) Cancer: 374 (91%) Other: 139 (89%) Laparotomy: 588 (91%) Laparoscopy: 87 (95%) Surgeon 114 (90%) Assistant 561 (92%) Stapled 57 (92%) Sutured 617 (91%) Urgent: 137 (88%) Elective: 538 (92%) 121 (85%) 554 (93%) 584 (92%) 91 (86%) 144 (49 – 497) 195 (75 – 630) 791 p value 0.001 0.953 0.951 0.918 0.277 0.116 1.000 0.203 0.831 0.974 1.000 1.000 0.114 0.460 1.000 0.075 0.249 0.328 0.603 1.000 0.110 0.006 0.029 0.038 0.012 BMI Body mass index (kg/m2 ), SD standard deviation, ASA American Society of Anesthesiologists a BMI missing 47 (6,4%) b Expressed in median and range c Data do not add up to 739 due to occasional missing of data d MBP unknown in 108 (14,5%) patients e During-hours is defined as the hours in which a new elective procedure was allowed to start (i.e. between 7.45 h and 15.30 h). After-hours is defined as the period in which patients were operated upon by the operating team that is on call (i.e. between 15.30 h and 7.45 h). f The group with nine non-traditional resections (“other” in Table 2) was excluded for risk factor analysis resections and 96 low anterior resections after the total mesenterial excision principle (TME). Nine patients under- went non-traditional resections, consisting of eight anasto- mosis without resection when intraoperatively, the tumor appeared to have progressed to far and one resection of transverse and descending colon. These nine patients were excluded for further risk factor analysis. A total of 92 (13%) operations were performed laparoscopically, of which 38 (41%) were converted. The population is described in Table 1.