Anorectal dynamics of Bu-Zhong-Yi-Qi decoction with biofeedback therapy for fecal incontinence after anus-preserving surgery in patients with low rectal cancer

Abstract

Objective To evaluate the effect and mechanism of Bu-Zhong-Yi-Qi decoction with biofeedback therapy on defecation dysfunction after anus-preserving surgery in patients with low rectal cancer through anal defecation function and anorectal dynamic indexes. Methods 120 patients with low rectal cancer preparing for anterior resection were randomized for three groups (45 cases of groups A and B, and 30 cases of group C). Group A was treated with Bu-Zhong-Yi-Qi decoction with biofeedback therapy for 3 months after the operation, group B was only treated with biofeedback, and group C was not given special treatment. Before operation, 2 weeks after operation and 2, 6, 10 and 14 months after intervention, the indexes about the change of defecation function and anorectal dynamics were continuously observed. Results There was no significant difference between group A and group B at 14th month after intervention in anal canal resting pressure (t=1.467, P=0.146), maximum anal canal systolic pressure (t=0.774, P=0.441), rectal threshold sensory capacity (t=1.856, P=0.067), rectal sense of sensory capacity (t=1.498, P=0.138) and rectal maximum tolerance (t=0.893, P=0.374), and those were (47.8±8.3), (188.8±19.2) mmHg (1 mmHg=0.133 kPa), (22.4±4.5), (48.1±9.9), (187.4±25.8) ml in group A. As compared with group C, the resting pressure of anal canal (t=10.018, P=0.000), the maximum systolic pressure of the anal canal (t=15.460, P=0.000) and the maximum rectal tolerance (t=12.835, P=0.000) at 14th month after treatment were significantly increased in group A , while the rectal threshold sensory capacity (t=1.546, P=0.127) and the rectal defecation capacity (t=1.754, P=0.084) showed no statistically significant difference between group A and group C. As compared with group C, the resting pressure of the anal canal (t=9.239, P=0.000), the maximum systolic pressure of the anal canal (t=16.543, P=0.000) and the maximum rectal tolerance (t=11.995, P=0.000) were significantly increased in group B [(45.2±7.6), (185.8±15.8) and (182.4±26.5) mmHg], and the rectal threshold sensory capacity (t=-0.009, P=0.993) and the rectal defecation capacity (t=0.476, P=0.636) showed no statistically significant difference [(20.6±4.4) and (44.9±9.9) ml]. In groups A and B, the number of patients with defecation function in general (6-5 points) and poor (less than 4 points) at 14th month after treatment was significantly increased as compared with that before treatment (χ2=13.105, P=0.000; and χ2=14.419, P=0.000, respectively) and in group C (χ2=15.238, P=0.000; χ2=14.364, P=0.000, respectively). There was no significant difference between group A and group B (χ2=0.025, P=0.874). Conclusion Bu-Zhong-Yi-Qi decoction with biofeedback therapy can effectively treat the defecation dysfunction after anus preserving operation in patients with low rectal cancer, mainly by tonifying Qi, invigorating splenic yang, and accelerating the recovery of anal sphincter function. Key words: Bu-Zhong-Yi-Qi decoction; Biofeedback therapy; Low rectal caicinoma; Fecal incontinence