Undergoing an Anorectal Physiology Test and Proctogram Content from the guide to life, the universe and everything

Undergoing an Anorectal Physiology Test and Proctogram

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The anorectal physiology test and the proctogram are tests used by specialist doctors to investigate the well-being and function of the rectum and anus in a patient who has experienced potentially serious problems with the function of the lower end of their bowel. The anorectal physiology test looks at the functioning of the muscles in this region, while a proctogram looks at the general function of the rectum through the use of barium paste, which outlines the inside of the rectum on X-Ray.

One h2g2 Researcher has experienced both the above tests in order to investigate a long history of peri-anal abscesses1. The factual parts of this Entry are therefore interlaced with the subjective resume of how the Researcher experienced the examination, the aim being that this account can allay the fears of others preparing to undergo such investigations.

Attending an examination of the nether regions is probably no one's idea of a good time. Most people are very sensitive and possibly inhibited about discussing that most basic of functions, elimination, and the associated areas of the rectum and anus.
Firstly, it is important to remember that although it may not be the norm for the individual to have medical measuring devices inserted into their rectums on a daily basis, the medically-appointed person's perspective differs. The patient is advised to accept that it may be a good idea to leave their idea of normality at the door of the examination room and accept the normality beyond. The patient is there to assist in the investigation and future management of a possible bowel condition, which can include bowel cancer, diverticulitus and fistulae. The doctor is there to investigate and diagnose.
Do bear in mind, though, that during the course of most of these examinations, the patient's back is turned to the examining professional, with their knees tucked up preferably to their chest, and their toes pointing at a 90 degree angle to their knees, rather than the more instinctive desire to tuck their toes firmly between their buttocks in order to impede the examination.

This Entry should note that there are usually leaflets available from hospitals, providing details of investigations they perform, along with such sage advice as that of not driving yourself home or travelling alone when you've been sedated earlier that day. However, one question not usually answered is whether the instruments used are wincingly hot or perishingly cold - in the case of anorectal examination, the instruments tend to be plastic and so their temperature is not likely to be at the front of one's mind.

Colonic Transit

As a prelude to the big day, some patients may be asked to swallow some markers which can be seen on X-Ray. This usually happens a number of days before the patient arrives for the investigation, with the markers often being contained in a small swallowable capsule. The markers will move through the gut at the same rate as food, and thus allow the colonic transit time - the time it takes for food to traverse the large bowel - to be measured.

X-Rays are taken to see how far the markers have made it through the bowel, thus giving an indication of how quickly the large bowel can process food. The more markers there are, and the higher up they are when the X-Rays are taken, the poorer the action of the bowels. The main problems with this test are that it can take several days for the markers to transit the bowel, and that the patient may need to avoid any laxatives, opiates or other drugs which might affect bowel motility. The test is used in patients with chronic constipation and other serious gut motility problems, and so the Researcher in question did not have this test.

Rectal Sensation

This is the first part of the anorectal physiology test, and so before starting, the patient will be laid on their left side with their lower half exposed, but with a blanket or sheet over the rest of them. First, the rectum is manually examined to test whether the patient can push and squeeze using the sphincters and muscles, and also to ensure that the rectum is empty - if not, an enema can be used to produce a bowel motion.

Once this is done, a catheter (small tube) with a balloon is inserted into the rectum and inflated, during which the patient is asked to describe the sensation this causes. The doctor may also look for signs of nerve reflex action, as this, too, indicates the presence of good sensation and muscle action.

In this Researcher's experience, it was found to be a wise course of action not to ask what colour the balloon was, nor how in reality the balloon was inflated. The obvious answer is, of course, by pumping air into the balloon manually. Objectively, the colour of the balloon is of no importance whatsoever.
Subjectively, this Researcher found this particular examination painless, albeit with unfamiliar sensations which were not particularly enjoyable. Conversely, they were not painful, either, merely unfamiliar.

Anal Pressure Measurements

The doctor may opt to test the pressure produced by the anal sphincters. The test involves the insertion of another catheter into the rectum which the patient is then asked to squeeze upon. The catheter may also be withdrawn repeatedly while the patient either relaxes or squeezes.

Again, the sensation is strange, rather than painful, mainly because such a small tube is difficult to locate purely by muscle power alone.

Pudendal Nerve Function Tests

This test looks at the function of the branches of the pudendal nerve, which controls the anal sphincter as well as other muscles in the pelvic region. The test uses a small probe to pass a tiny electrical current into the nerves, causing the muscles to twitch. The response by the muscles these nerves control can be recorded using a computer. The test is an optional extra, and may be used depending on the condition being looked into or the findings of the previous tests.

The leaflet warns that the patient may feel a pulsing, twitching or a prickling sensation while measurements are being taken. However, despite the initial horror of the word electrodes being used, this Researcher experienced only a mild sensation akin to the twitching of an eyelid, although in this case internally, when the examination was being carried out.
In this Researcher's opinion, the description of this particular test, as illustrated in the leaflet usually sent to patients prior to the examination, sounds considerably more dramatic and frightening than it actually is.


Another added extra, an ultrasound scanner can be inserted into the rectum in order to produce a scan of the muscles, thus showing up any damage. While ultrasound scanners do not irradiate the patient in the way that X-Ray machines do, the probe used is slightly bigger than a catheter and may be somewhat less pleasant.

A finger-sized probe, which this researcher found slightly invasive, albeit painless, is inserted into the back passage and gently moved in and out, so that scans can be taken at different positions within the rectum. Do not, at any time, be tempted to smile for the camera; it is a complete waste of time.

Evacuation Proctography

Once the anorectal physiology test is out of the way, the real fun starts. A mixture of barium paste and soft solids such as oatmeal or mashed potato is inserted into the rectum, following which the patient is asked to sit upon a commode and perform various motions - including a bowel motion. The barium shows up on X-Ray, and can thus be seen on a fluoroscope, a kind of X-Ray television.

Depending on one's attitude, this is possibly the test that is the socially and psychologically most challenging. It is a given that all living things evacuate waste produce, but it seems to be a human quirk that very few humans are relaxed enough to admit this fact. In this particular test, it is advisable to accept that every person - including oneself - does, and that it is a perfectly normal function; even though, at the time, the means are artificial.
For the sake of expediency, a mixture of barium paste, saline and, in this particular case, porridge oats, are inserted into the rectum via an examining scope - which appeared to be shaped suspiciously like a large icing syringe - until the patient has the urge to pass stool.
The patient is then asked to climb down from the examination table and, carefully controlling their bowels if they are able to do so, seat themselves onto a specially designed toilet. Privacy is offered by the means of a screen and a darkened room, and the consultant instructs the patient to empty their bowel into the commode; the process is observed objectively by the doctor via cameras which relay images to their computer, thus enabling them to complete the tests.

On The Process As A Whole

The entire process, colonic transition excluded, takes around 55 minutes, and although at first sight appearing daunting, it is nothing as bad as the patient in the waiting room could imagine it to be. If the consultant or his/her assistants are willing to interact verbally with the patient, the process can at the very least be completely bearable. This Researcher found the whole procedure slightly uncomfortable mentally, but not particularly uncomfortable physically.
Obviously a sense of proportion, a lack of self consciousness, and an acceptance of one's bodily functions are fairly essential, but as this Researcher's consultant remarked 'It may not feel normal to you, because you don't have this done every day and therefore it's unfamiliar. You have to remember I do this for a living, I choose to do it, and this is my normality.'
When this sage advice is borne in mind, then this procedure could be summed up thusly: if you've been referred by your GP or hospital consultant to undergo it - attend the appointment. It's well worth the potential embarrassment and fear if, once diagnosed, the ailment you have can be cured or at least made far more manageable in the long term.
1Pus-filled cavities around the region of the anus.

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