Correcting for non-compliance when determining colonic transit time with radio-opaque markers

The use of radio-opaque markers and abdominal X-ray is the standard method for determining colonic transit time(CTT). However, when there are deviations in the intake of these markers by participants in clinical trials it is desirable to improve observations by introducingcorrections, where possible. To date, there is no standard procedure to adjust for such deviations. This report proposes a series of alternatives based on possible scenarios for deviations from the intended intake of radio-opaque markers. The proposed method to correct for missed or delayed consumption of radioopaque markers can help to increase the accuracy of the CTT measurements in clinical trials.

Preservation of superior rectal artery in laparoscopically assisted subtotal colectomy with ileorectal anastomosis for slow transit constipation

BACKGROUND Slow transit constipation(STC)has traditionally been considered as a functional disorder.However,evidence is accumulating that suggests that most of the motility alterations in STC might be of a neuropathic etiology.If the patient does not meet the diagnosis of pelvic outlet obstruction and poorly response to conservative treatment,surgical intervention with subtotal colectomy may be effective.The most unwanted complication of the procedure is anastomotic leakage,however,preservation of the superior rectal artery(SRA)may reduce its incidence.AIM To evaluate the preservation of the SRA in laparoscopically assisted subtotal colectomy with ileorectal anastomosis in STC patients.METHODS This was a single-center retrospective observational study.STC was diagnosed after a series of examinations which included a colonic transit test,anal manometry,a balloon expulsion test,and a barium enema.Eligible patients underwent laparoscopically assisted total colectomy with ileorectal anastomosis and were examined between January 2016 and January 2018.The operation time,blood loss,time to first flatus,length of hospital days,and incidence of minor or major complications were recorded.RESULTS A total of 32 patients(mean age,42.6 years)who had received laparoscopic assisted subtotal colectomy with ileorectal artery anastomosis and preservation of the SRA.All patients were diagnosed with STC after a series of examinations.The mean operative time was 151 min and the mean blood loss was 119 mL.The mean day of first time to flatus was 3.0 d,and the mean hospital stay was 10.6 d.There were no any patients conversions to laparotomy.Post-operative minor complications including 1 wound infection and 1 case of ileus.There was no surgical mortality.No anastomosis leakage was noted in any of the patients.CONCLUSION Laparoscopically assisted subtotal colectomy with ileorectal anastomosis and preservation of the SRA can significantly improve bowel function with careful patient selection.Sparing the SRA may protect against anastomosis leakage.

Correlation between colonic secretion and colonic motility in rats: Role of ghrelin

AIM To explore the relationship between colonic secretory function and colonic motility.METHODS Using a rat model chronically implanted with intracerebroventricular(ICV) and cecal catheters, we validated the correlation between colonic secretion and colonic motor functions, as well as the role of ICV injection volume.RESULTS Compared to saline controls(5 μL/rat), ICV acyl ghrelin at 1 nmol/5 μL enhanced the total fecal weight, accelerated the colonic transit time, and increased the fecal pellet output during the first hour post-injection, while ICV des-acyl ghrelin at 1 nmol/5 μL only accelerated the colonic transit time. These stimulatory effects on colonic motility and/or secretion from acyl ghrelin and des-acyl ghrelin disappeared when the ICV injection volume increased to 10 μL compared with saline controls(10 μL/rat). Additionally, the ICV injection of 10 μL of saline significantly shortened the colonic transit time compared with the ICV injection of 5 μL of saline. The total fecal weight during the first hour post-injection correlated with the colonic transit time and fecal pellet output after the ICV injection of acyl ghrelin(1 nmol/5 μL), whereas the total fecal weight during the first hour post-injection correlated with the fecal pellet output but not the colonic transit time after the ICV injection of des-acyl ghrelin(1 nmol/5 μL).CONCLUSION Colonic secretion does not always correlate with colonic motility in response to different colonic stimulations. Acyl ghrelin stimulates colonic secretion.

Increased colon transit time and faecal load in irritable bowel syndrome

BACKGROUND Irritable bowel syndrome(IBS)is a bowel disorder involving abdominal pain or discomfort along with irregularity of stool form and passage frequency.The pathophysiology is poorly understood and seems to be multifactorial.Investigations of possible causes of IBS have included only a few colonic transit studies and no simultaneous determination of the colonic faecal content.AIM To compare colon transit time and faecal load between IBS-patients and healthy control subjects.METHODS The study included 140 patients with IBS,with a mean age of 50.0 years.The control group comprised 44 healthy persons with a mean age of 43.4 years,who were selected at random from the National Civil Register.Both the patient group and the control group underwent a marker study to measure colon transit time(CTT)and to calculate a faecal loading score.The patient group underwent treatment with a combined prokinetic regime,after which their CTT and faecal loading were reassessed.Analyses were performed to compare measurements between the control group and the patient group before and after treatment.RESULTS Compared to healthy controls,IBS-patients exhibited a significantly prolonged mean CTT(45.48 h vs 24.75 h,P=0.0002)and significantly greater mean faecal loading scores in all colonic segments(P<0.001).Among IBS patients,we found no significant differences between the 48 h and 96 h radiographs.Among patients exhibiting increased CTT and faecal loading,approximately half exhibited a palpable mass in the right iliac fossa.After intervention with a prokinetic treatment,the mean CTT among IBS patients was reduced from 45.48 h to 34.50 h(P=0.091),with the post-treatment CTT not significantly differing from the CTT among control subjects(P=0.095).The faecal loading score among IBS patients did not significantly differ before and after treatment(P=0.442).The posttreatment faecal loading score in IBS patients remained significantly higher compared to that in controls(5.3 vs 4.3,P=0.014).After treatment,half of the IBSpatients were relieved of bloating,while the majority no longer experienced abdominal pain and achieved a daily consistent stool.CONCLUSION IBS-patients exhibited prolonged CTT and heavier faecal loading.These assessments may aid in diagnosis.Faecal retention may contribute to IBS symptoms,which can be treated using a prokinetic regime.

Aerobic exercise improves gastrointestinal motility in psychiatric inpatients

AIM: To evaluate the benefit of aerobic exercise on colonic transit time (CTT) for psychiatric inpatients in a closed ward.

Study on the characteristics of intestinal motility of constipation in patients with Parkinson's disease

BACKGROUND Constipation is one of the most important nonmotor symptoms in Parkinson's disease(PD)patients,and constipation of different severities is closely related to the pathogenesis of PD.PD with constipation(PDC)is considered a unique type of constipation,but its mechanism of formation and factors affecting its severity have been less reported.Understanding the gastrointestinal motility characteristics and constipation classification of PDC patients is essential to guide the treatment of PDC.In this study,the colonic transit test and high-resolution anorectal manometry were used to identify the intestinal motility of PDC to provide a basis for the treatment of PDC.AIM To investigate the clinical classification of PDC,to clarify its characteristics of colonic motility and rectal anal canal pressure,and to provide a basis for further research on the pathogenesis of PDC.METHODS Twenty PDC patients and 20 patients with functional constipation(FC)who were treated at Xuanwu Hospital of Capital Medical University from August 6,2018 to December 2,2019 were included.A colonic transit test and high-resolution anorectal manometry were performed to compare the differences in colonic transit time,rectal anal canal pressure,and constipation classification between the two groups.RESULTS There were no statistically significant differences in sex,age,body mass index,or duration of constipation between the two groups.It was found that more patients in the PDC group exhibited difficulty in defecating than in the FC group,and the difference was statistically significant.The rectal resting pressure,anal sphincter resting pressure,intrarectal pressure,and anal relaxation rate in the PDC group were significantly lower than those in the FC group.The proportion of paradoxical contractions in the PDC group was significantly higher than that in the FC group.There was a statistically significant difference in the type composition ratio of defecatory disorders between the two groups(P<0.05).The left colonic transit time,rectosigmoid colonic transit time(RSCTT),and total colonic transit time were prolonged in PDC and FC patients compared to normal values.The patients with FC had a significantly longer right colonic transit time and a significantly shorter RSCTT than patients with PDC(P<0.05).Mixed constipation predominated in PDC patients and FC patients,and no significant difference was observed.CONCLUSION Patients with PDC and FC have severe functional dysmotility of the colon and rectum,but there are certain differences in segmental colonic transit time and rectal anal canal pressure between the two groups.

Use of a device that applies external kneading-like force on the abdomen for treatment of constipation

AIM: To evaluate the efficacy of a recently developed device that applies kneading-like motion on the abdomen in improving constipation in elderly long-term care patients. METHODS: Thirty constipated elderly patients were randomly selected from two nursing homes. They were instructed to use the device once daily for 20 min. Rate of bowel movements, volume and consistency of stool and the use of laxantia were all recorded during a 3-wk baseline period and for 12-wk treatment period. Colonic transit time (CTT) was measured in 13 patients by radiopaque markers during the baseline and at the end of treatment. RESULTS: Bowel movement rate (BM/week) increased from 1.4±0.4 BM/wk during baseline to 3.9±0.8 BM/wk during treatment (P<5.0×10-7). Stool amount that was 'low' in 30 patients during baseline increased in 21 patients at the end of the study period (x2 = 19.048-P= 1.3×10-5). Stool consistency,that was 'hard' in 25 patients and 'soft' in 5 patients during baseline, ameliorated in 23 patients at the end of the study (only 2 patients referred 'hard' stool) (x2 = 21.043-P= 4.0×10-6). The mean baseline CTT measured was 92.3±32.3 h at baseline and decreased to 49.4±31.3 h during the study period (P = 0.000208). No side effects were observed during the study period. CONCLUSION: External mechanical vibration of the abdomen reduced CTT and helped to relieve severe constipation in elderly constipated patients.