Narrow pelvic inlet plane area and obesity as risk factors for anastomotic leakage after intersphincteric resection

Table 1 Univariate analyses of clinicopathological variables related to anastomotic leakage after intersphincteric resection

	No leakage	Leakage	P value
Patients number	107	10
Age in yr	61.1 ± 12.7	64.3 ± 9.9	0.436
Male sex, n (%)	80 (74.8)	9 (90)	0.489
Body mass index	22.4 ± 3.3	25.6 ± 2.7	0.004
Anesthesiologists physical status			0.569
1	29	3
2	75	7
3	3	0
Serum total protein level, g/dL	6.9 ± 0.5	7.1 ± 0.5	0.351
Blood hemoglobin level, g/dL	13.5 ± 1.8	14.6 ± 1.4	0.055
Prognostic nutritional index	49.7 ± 6.3	52.4 ± 4.9	0.205
Diabetes mellitus			0.326
No	93	7
Yes	14	3
Inlet plane: Antero-posterior diameter, mm	110.3 ± 10.8	100 ± 7.9	0.002
Inlet plane: Transverse diameter, mm	156.3 ± 35.4	136.4 ± 17.7	0.008
Area of the inlet plane, mm2	11330 ± 1279	9428 ± 636.1	< 0.001
Outlet plane: Antero-posterior diameter, mm	97.8 ± 8.9	90.6 ± 10.4	0.018
Outlet plane: Transverse diameter, mm	103.4 ± 10.1	102.8 ± 4.4	0.739
Area of the outlet plane, mm2	9572 ± 1501	9323 ± 999	0.487
Length of the pubic symphysis, mm	41.9 ± 5.6	45.7 ± 5.2	0.044
Distance from the sacral promontry to the coccyx, mm	125.5 ± 13.3	131.3 ± 14.8	0.193
Tortuosity angle	131.7 ± 8.7	140.4 ± 11.4	0.004
Tumors
Tumor size, mm	41.3 ± 25.2	33.3 ± 19.7	0.335
Distance from the anal verge, mm	16.8 ± 19.2	20.4 ± 14.6	0.563
TNM stage			0.056
0	3	1
I	35	6
II	23	1
III	34	1
IV	12	1
Preoperative radiotherapy			0.972
No	90	9
Yes	17	1
Neoadjuvant chemotherapy			0.341
No	89	10
Yes	18	0
Surgery			0.341
Laparotomy	89	10
Laparoscopic surgery	18	0
Circumferential resection margin			0.809
No	100	9
Yes	7	1
Ligated site of the artery			0.583
Inferior mesenteric artery	5	0
Left colonic artery	41	3
Sigmoid colon artery	61	7
Mobilization of the splenic flexure			0.738
No	99	9
Yes	8	1
Diverting stoma			0.401
No	1	1
Yes	106	9
Anal bougie			0.341
No	89	10
Yes	18	0
Bleeding amount, mL	645 ± 709	1380 ± 1166	0.004
Blood transfusion, mL	8 ± 60	292 ± 621	0.181
Operator			0.418
X	87	9
T	9	1
S	11	0
Operation time in min	367 ± 156	387 ± 167	0.698
Curativity			0.54
A	86	9
B	8	0
C	13	1

TNM: Tumor-node-metastasis.

Table 2 Multivariate analyses of clinicopathological variables related to anastomotic leakage after intersphincteric resection

Variables	Multivariate analysis
	Odds ratio	95%CI	P value
Body mass index	1.674	1.087-2.58	0.019
Area of the inlet plane	0.998	0.997-0.999	0.012
Outlet plane: Antero-posterior diameter	0.905	0.811-1.008	0.07
Length of the pubic symphysis	1.125	0.883-1.435	0.341
Tortuosity angle	1.049	0.941-1.17	0.39
Bleeding amount	1.001	0.999-1.003	0.144

CI: Confidence interval.