Anorectal function after low anterior resection of the rectum

Abstract

Impaired neorectal function or sphincter incompetence have been respectively implicated as causative factors of increased frequency of defaecation or incontinence after low anterior resection of the rectum (LARR) for rectal carcinoma, although individual mechanisms of anorectal function have not been fully studied. Functional and laboratory results were evaluated in 19 subjects, who had a LARR for rectal carcinoma before and after the procedure, and were compared to those of normal subjects. LARR worsened anorectal function, mostly by significantly increasing the daily number of defaecations (p < 0.001), while major incontinence was reported in three cases. Patients with rectal carcinoma have a decreased resting anal pressure on manometry, as compared to controls (p < 0.001). LARR further reduces anal resting pressure (p < 0.001) as well as all parameters that express internal sphincter activity, such as presence and amplitude of either slow (p < 0.05 and p < 0.01) or ultraslow waves. LARR also impaired external anal sphincter activity, as expressed by the reduction in anal squeeze pressure (p < 0.001). Anorectal sampling was found reduced in incidence and frequency in LARR patients as compared to controls (p < 0.01 and p < 0.001), and was impaired even further postoperatively (p < 0.001). Rectoanal inhibitory reflex was present in all but three patients postoperative, but significantly impaired as compared to controls. Rectal volumes to elicit transient or permanent desire to defecate, maximal tolerable rectal volume and rectal compliance were also significantly reduced after LARR (p < 0.001, p < 0.001, p < 0.01 and p < 0.001 respectively). Large bowel transit was significantly enhanced after LARR (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Resection rectopexy for rectal prolapse

“…All patients were assessed preoperatively and 6-9 months postoperatively by clinical examination, anorectal manometry, estimation of large-bowel transit, defecography, and ultrasonography of the anorectum according to standard techniques and definitions [14,15]. Their outcome was compared to that of a historical control group of eight female patients, matched for age (71 ± 13 years; range, 51-85 years) and parity, who underwent resection rectopexy through the open approach for overt rectal prolapse (OPEN).…”

Poor Neorectal Evacuation as a Cause of Impaired Defecatory Function After Low Anterior Resection: A Study Using Scintigraphic Assessment

“…11 However, few studies on the relationship between neorectal evacuation and defecatory function after LAR have been conducted. 12,13 In the present study, scintigraphic assessment of neorectal evacuation was done in patients who underwent LAR with a straight anastomosis. We examined the relationship between neorectal evacuation and clinical defecatory function, clinical factors, and anorectal manovolumetric parameters.…”

Causes and Prevention of Functional Disturbances Following Low Anterior Resection for Rectal Cancer

“…The reservoir function of the remaining rectum or the rectal replacement can be quantified with these parameters. A post-operative reduction in these parameters could be measured in patients compared with pre-operatively (5, 25,89,115,123,161), as well as in patients compared with healthy controls (25,39,154,158). Compliance is also influenced by the height of the anastomosis and the length of the rectal stump.…”

“…Compliance is also influenced by the height of the anastomosis and the length of the rectal stump. Anastomotic leakages (44,115) with consecutive scarring of the wall of the replacement rectum or the remaining rectum and late radiation reactions following adjuvant radio chemotherapy with the formation of a rigid wall in the neorectum naturally also result in reduced compliance, and thus to deterioration in the reservoir function 3.2 Reduction in resting anal pressure (RP) due to stretching trauma Many manometric studies before and after low anterior resection have shown a reduction in resting anal pressure up to one year post-operatively compared with pre-operatively, regardless of whether the reconstruction had been made with a colon pouch or with a straight coloanal or colorectal anastomosis (5, 25,30,37,66,69,72,74,89,158,161). As might be…”