Efficacy of staple line reinforcement by barbed suture for preventing anastomotic leakage in laparoscopic rectal cancer surgery

Table 1 Baseline characteristics of patients (n = 319)

Variables	Reinforcing sutures		P value
	Yes, n = 168	No, n = 151
Age (yr)	61.8 ± 8.7	63.0 ± 9.7	0.229
Men/Women	80/88	73/78	0.897
BMI (kg/m2)	23.2 ± 3.6	22.8 ± 3.8	0.378
ASA score, n (%)			0.948
1	60 (35.7)	54 (35.8)
2	67 (39.9)	61 (40.4)
3	41 (24.4)	36 (23.8)
Tumor diameter (cm)	4.4 ± 1.7	4.1 ± 1.8	0.178
Tumor site (from anal verge, cm), n (%)			0.641
≥ 5	123 (73.2)	114(75.5)
< 5	45 (26.8)	37(24.5)
Depth of tumor invasion, n (%)			0.295
T1-T2	33 (19.6)	37 (24.5)
T3-T4	135 (80.4)	114 (75.5)
Lymph node metastases, n (%)			0.493
Yes	77 (45.8)	75 (49.7)
No	91 (54.2)	76 (50.3)
Diabetes mellitus, n (%)	31 (18.5)	22 (14.6)	0.352
Hypertension, n (%)	37 (22.0)	25 (16.6)	0.218
Heart disease, n (%)	18 (10.7)	11 (7.3)	0.287
COPD, n (%)	9 (5.4)	7 (4.6)	0.768
Previous abdominal surgery, n (%)	17 (10.1)	14 (9.3)	0.799
Preoperative CEA (ng/mL), n (%)			0.430
≥ 5	57 (33.9)	45 (29.8)
< 5	111 (66.1)	106 (70.2)
Preoperative hemoglobin levels (g/L), n (%)			0.239
≥ 90	138 (82.1)	116 (76.8)
< 90	30 (17.9)	35 (23.2)
Preoperative serum albumin level (g/L), n (%)			0.301
≥ 35	139 (82.7)	118 (78.1)
< 35	29 (17.3)	33 (21.9)
Preoperative serum CRP level (mg/L), n (%)			0.375
≥ 10	28 (16.7)	28 (20.5)
< 10	140 (83.3)	123 (79.5)

BMI: Body mass index; ASA: American society of anesthesiologists; COPD: Chronic obstructive pulmonary disease; CEA: Carcinoma embryonic antigen; CPR: C-reactive protein.

Table 2 Surgical outcomes and postoperative complications

Variables	Reinforcing sutures		P value
	Yes, n = 168	No, n = 151
Left colic artery ligation, n (%)			0.637
Yes	79 (47.0)	75 (49.7)
No	89 (53.0)	76 (50.3)
Number of staple firings, n (%)			0.902
≥ 3	16 (9.5)	15 (9.9)
< 3	152 (90.5)	136 (90.1)
Operation time (min)	150.4 ± 25.1	146.6 ± 20.2	0.135
Intraoperative transfusion, n (%)	20 (11.9)	15 (9.9)	0.574
Intraoperative blood loss (mL)	60.5 ± 43.9	58.2 ± 46.3	0.652
Complications, n (%)
Anastomotic leakage	8 (4.8)	17 (11.3)	0.031
Postoperative intestinal obstruction	25 (14.9)	17 (11.3)	0.339
Anastomosis stricture	12 (7.1)	17 (13.1)	0.202
Postoperative defecation dysfunction, 3 mo	31 (18.5)	25 (16.6)	0.657
Postoperative defecation dysfunction, 6 mo	23 (13.7)	21 (13.9)	0.955
Postoperative defecation dysfunction, 12 mo	12 (7.1)	9 (6.0)	0.671

Table 3 Anastomotic leakage related indices (n = 25)

	Reinforcing sutures		P value
	Yes, n = 8	No, n = 17
AL classification			0.020
Grade A	3	2
Grade B	3	2
Grade C	2	13
AL time (d)	5 (2–7)	4 (1–7)	0.715
Treatment
Trans-anal lavage and drainage	2	1	0.231
Peritoneal lavage and drainage	1	1	1.000
Reoperation	2	13	0.028

AL: Anastomotic leakage.

Table 4 Univariate and multivariate regression on anastomotic leakage-related factors (n = 319)

Variables	Univariate regression			Multivariate regression
	OR	95%CI	P value	OR	95%CI	P value
Male gender	1.189	0.523–2.705	0.680
Age ≥ 60 (yr)	2.123	0.824–5.473	0.119
BMI ≥ 25 (kg/m2)	1.115	0.448–2.775	0.814
Diabetic mellitus	2.604	1.060–6.394	0.037	1.662	0.588–4.669	0.338
Hypertension	1.039	0.374–2.888	0.941
Heart disease	2.050	0.652–6.441	0.219
COPD	1.739	0.372–8.124	0.482
Low tumor location < 5 (cm)	2.954	1.289–6.769	0.010	2.856	1.133–7.198	0.026
Tumor diameter ≥ 4 (cm)	3.010	1.313–6.901	0.009	2.994	1.185–7.563	0.020
T3-T4	1.135	0.410–3.142	0.807
Lymph node metastases	1.719	0.748–3.951	0.202
Previous laparotomy	1.884	0.602–5.890	0.276
Preoperative CEA ≥ 5 (ng/mL)	1.216	0.518-2.852	0.653
Preoperative serum albumin level < 35 (g/L)	1.690	0.673–4.244	0.264
Preoperative hemoglobin levels < 90 (g/L)	1.582	0.631–3.967	0.328
Preoperative serum CRP level, ≥ 10 (mg/L)	2.242	0.918–5.476	0.076
ASA score ≥ 3	1.244	0.499–3.102	0.639
Ligation of left colic artery	2.435	1.019–5.819	0.045	2.195	0.869–5.546	0.096
Operation time ≥ 150 (min)	2.437	1.059–5.613	0.036	1.837	0.750–4.495	0.183
Number of staple firings ≥ 3	2.577	0.893–7.434	0.080
Intraoperative transfusion	1.116	0.316–3.939	0.864
Intraoperative blood loss ≥ 60 (mL)	1.223	0.537–2.787	0.632
Reinforcing sutures	0.394	0.165–0.942	0.036	0.293	0.114–0.750	0.010
Postoperative intestinal obstruction	2.263	0.848–6.041	0.103

OR: Odds ratio; CI: Confidence interval; BMI: Body mass index; COPD: Chronic obstructive pulmonary disease; CEA: Carcinoma embryonic antigen; CPR: C-reactive protein; ASA: American society of anesthesiologists.

Table 5 Subgroup analysis of the effectiveness of reinforcing sutures

Reinforcing sutures	Anastomotic leakage		P value
	Yes	No
Low-risk group			0.368
Yes	1	87
No	4	85
High-risk group			0.038
Yes	7	73
No	13	49