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Healthy female volunteer study to examine the effect of different body positions and environment on defecation physiology

Healthy female volunteer study to examine the effect of different body positions and environment on defecation physiology

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ANZCTR
Registry ID
ACTRN12623000471684
Enrollment
32
Registered
2023-05-09
Start date
2023-03-22
Completion date
2025-12-31
Last updated
2025-09-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

This study is a healthy volunteer study assessing anorectal function during defecation. The balloon expulsion study is one of the diagnostic tests used to assess dyssynergic defecation - condition where there is a poor coordination of pelvic floor muscle resulting in impaired defecation. In this study, participants will be asked to undergo anorectal ultrasound, anorectal manometry followed by rectal balloon expulsion tests in three different positions. Balloon expulsion time and the ease and comfort of balloon expulsion will be compared between different positions and environments. Result from this tests will contribute to further refining the interpretation and performing balloon expulsion test.

Interventions

Firstly, participants will undergo baseline assessment that includes anorectal ultrasound and anorectal manometry. Anorectal ultrasound involves examination of the anal sphincters using a transrectal ultrasound probe. Then participants will undergo anorectal manometry. Participants will have a flexible catheter inserted into rectum to measure the rectal and sphincter pressure during various manoeuvres including balloon expulsion. Rectal sensation will be measured by inflating rectal balloon. H

Firstly, participants will undergo baseline assessment that includes anorectal ultrasound and anorectal manometry. Anorectal ultrasound involves examination of the anal sphincters using a transrectal ultrasound probe. Then participants will undergo anorectal manometry. Participants will have a flexible catheter inserted into rectum to measure the rectal and sphincter pressure during various manoeuvres including balloon expulsion. Rectal sensation will be measured by inflating rectal balloon. Healthy volunteers will be asked to expel rectal balloon in different settings - Supine and 2 sitting positions. For sitting positions: Setting 1) In a conventional toilet in privacy Setting 2) On a commode chair behind the curtain (partial privacy). Order in which balloons are expelled will be randomised. All participants will also undergo anorectal manometry and anal ultrasound. All procedures will be performed by either a doctor (gastroenterologist or advanced trainee for gastroenterology) or a specialist nurse. Participants will only need to attend one session lasting approximately 1-2 hours to complete the study.

Sponsors

Royal North Shore Hospital - Northern Sydney Local Health District
Lead SponsorHospital

Study design

Allocation
Randomised controlled trial
Intervention model
Single group
Primary purpose
Diagnosis
Masking
Open (masking not used)

Eligibility

Sex/Gender
All
Age
20 Years to 75 Years
Healthy volunteers
Yes

Inclusion criteria

1) Age 20 to 75 2) Females 3) English speakers 4) Patients who are eligible for Medicare benefit in Australia 5) Willingness to answer screening questionnaire 6) Willingness to give written informed consent 7) Willingness to comply with the study.

Exclusion criteria

1) Women breast feeding or pregnant. 2) Definable gastrointestinal disorder based on the ROME questionnaire : Disorders excluded: Irritable bowel syndrome, functional bloating, functional constipation or diarrhoea, abdominal pain and functional anorectal disorders. 3) Presence of overt organic anorectal disorder 4) Medications that alter motility of the GI tract, such as loperamide and opioids 5) History of anorectal or distal colon surgery. 6) History of complicated vaginal delivery 7) History of psychological illness or condition such as interfere with the patient’s ability to understand the requirements of the study. This will be assessed by: (a) hospital anxiety and depression score, (b) screening questionnaire questions about medical conditions and current medications, and (c) brief physician interview and discussion of patient information and consent form before patients consent.

Outcome results

None listed

Source: ANZCTR · Data processed: Sep 9, 2026