Study of Anal Sphincter Function and RAIR under GA and NMB using AAR
Research type
Research Study
Full title
A Study of Anal Sphincter Function and the Recto-inhibitory Reflex (RAIR) in patients receiving General Anaesthetic (GA) with Neuromuscular Blockade (NMB) using Anal Acoustic Reflectometry (AAR)
IRAS ID
231440
Contact name
Karen Telford
Contact email
Sponsor organisation
University Hospital of South Manchester
Duration of Study in the UK
1 years, 5 months, 3 days
Research summary
The recto-anal inhibitory reflex (RAIR) is the transient relaxation of the anal canal in response to distension of the rectum and it is important for the maintenance of continence. RAIR is traditionally measured using anal manometry. However, we discovered that it can be measured using anal acoustic reflectometry (AAR). AAR is a reliable and reproducible technique that has been studied in our department over the last 8 years. Sound waves pass into a balloon placed in the anal canal and by gradually increasing and decreasing the pressure in the balloon we can measure the pressure at which the cross-sectional area starts to increase and decrease, and the anal canal starts to open and close.
In order to elicit RAIR a small 1.7mm catheter is placed along side the AAR catheter and the rectum distended with 100mls. Measurements are taken as outlined above.The sphincter complex is made up of an internal and external sphincter (different types of muscles). Both play an important role in continence but the extent is still being investigated. In order to isolate the internal sphincter and establish its role in RAIR the external sphincter must be paralysed. This is routinely done when patients are having a general anaesthetic (GA) for operations that require the body to be fully relaxed. Medications are given to achieve this. Measuring RAIR before and during GA will allow us to fully establish the independent roles of the internal and external sphincters for continence, their effect on RAIR and the extent they rely on each other. This has never been investigated before and will provide us with important information about the sphincters and how they work. This will be important in formulating management plans for those patients with pelvic floor dysfunction and sphincter defects.
REC name
North West - Greater Manchester East Research Ethics Committee
REC reference
17/NW/0549
Date of REC Opinion
18 Oct 2017
REC opinion
Further Information Favourable Opinion