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Understanding Mechanisms of Normal and Disordered Defecation

Not Applicable
Recruiting
Conditions
Constipation
Interventions
Diagnostic Test: Rectal Barostat Study
Diagnostic Test: Fecoflowmetry
Registration Number
NCT03842007
Lead Sponsor
Mayo Clinic
Brief Summary

Researchers are trying to better understand why constipation occurs and improve the tests for diagnosing these conditions.

Detailed Description

Study includes a screening visit and a study day. During the initial screening visit for this study, subjects will complete three (3) questionnaires about their bowel symptoms, overall health, and anxiety and depression. A blood sample (about 4 tablespoons) will be drawn to study the relationship between genes and certain bowel habits. Subjects will be asked to provide a single stool sample to look at the bacteria in the stool.

Before the study, subjects will receive 1 to 2 Fleet's enemas to clean the rectum. After receiving the Fleet's enema (administered through a small plastic tube in the rectum), a swab attached to a small rectal catheter will be used to brush the lining of the rectum and obtain a stool specimen. Then, rectal and anal pressures will be measured by placing a small catheter (plastic tube) in the rectum, and withdrawing it slowly. Rectal sensation will be measured by inflating a small balloon in the rectum.

There are 2 procedures (rectal barostat study and fecomanoflowmetry), each of which lasts approximately 90 minutes. During the rectal barostat study, contractions will be recorded with a balloon inserted into the rectum and inflated. After the barostat study is completed, your rectum will be filled with a small amount of paste. Two thin catheters will be inserted into the anus to measure pressures and electrical activity (electromyography or EMG). Then, you will be asked to sit on a commode, contract (squeeze) your anal muscles, blow into a balloon, and expel the paste into the commode.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
160
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Healthy IndividualsFecoflowmetrySixty healthy individuals (20 men and 40 women) will undergo an anorectal study which comprises of a rectal barostat study followed by fecoflowmetry
Healthy IndividualsRectal Barostat StudySixty healthy individuals (20 men and 40 women) will undergo an anorectal study which comprises of a rectal barostat study followed by fecoflowmetry
Constipated IndividualsRectal Barostat Study60 constipated individuals (20 men and 40 women) will undergo an anorectal study which comprises of a rectal barostat study followed by fecoflowmetry
Constipated IndividualsFecoflowmetry60 constipated individuals (20 men and 40 women) will undergo an anorectal study which comprises of a rectal barostat study followed by fecoflowmetry
Primary Outcome Measures
NameTimeMethod
Rectal emptyingBaseline

Measured by fecomanoflowmetry calculating the mean and maximum flow rate in various conditions (mg/sec), defecated volume (mg), flow time (sec) and time to maximum flow (sec). The amount of artificial stool evacuated is expressed in milligrams. The duration is in seconds. These 2 metrics are integrated to measure mg evacuated/second.

Rectoanal pressuresBaseline

Measured by anorectal manometry in mmHg

Secondary Outcome Measures
NameTimeMethod
Rectal contractile response to distention measured with a sinusoidal oscillatorBaseline

Rectal balloon is inflated to a preload volume of 125ml. The balloon is then oscillated around baseline volume by 25mL for 20 min at a frequency of 5 counts per minute (cpm). The mean rectal pressure (cm H2O) will be calculated over the multiple oscillation cycles within the 20 minute distention segment.

Rectal compliance measured with a barostatBaseline

Pressure (mmHg) corresponding to half-maximum rectal volume during rectal distention

Rectal sensory threshold for first sensation to defecate using barostat balloon distentionBaseline

The sensory threshold for first sensation to defecate is measured by stepwise inflation of the balloon (0-44 mm Hg, at 4 mm Hg increments). During this assessment participants are asked to report when they have the first sensation to defecate.

Rectal Capacity measured with a barostatBaseline

Rectal volume (ml) at maximum distending pressure during rectal distention

Rectal sensory threshold for maximum urgency during barostat balloon distentionBaseline

The sensory threshold for maximum urgency to defecate is measured by stepwise inflation of the balloon (0-44 mm Hg, at 4 mm Hg increments). During this assessment participants are asked to report when they have the maximum urgency to defecate.

Rectal balloon expulsion timeBaseline

During this test, the time (seconds) required to expel a water-filled rectal balloon (50 ml) will be compared between healthy people and patients

Anal sphincter electromyography (EMG)Baseline

Units - mV

Rectal sensory threshold for desire to defecate using barostat balloon distentionBaseline

The sensory threshold for desire to defecate is measured by stepwise inflation of the balloon (0-44 mm Hg, at 4 mm Hg increments). During this assessment participants are asked to report when they have the desire to defecate.

Trial Locations

Locations (1)

Mayo Clinic in Rochester

🇺🇸

Rochester, Minnesota, United States

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