The Rectum

The Rectum

They say man has succeeded where the animals fail because of the clever use of his hands, yet when compared to the hands, the sphincter ani is far superior. If you place into your cupped hands a mixture of fluid, solid and gas and then through an opening at the bottom, try to let only the gas escape, you will fail. Yet the sphincter ani can do it. The sphincter apparently can differentiate between solid, fluid and gas. It apparently can tell whether its owner is alone or with someone, whether standing up or sitting down, whether its owner has his pants on or off. No other muscle in the body is such a protector of the dignity of man, yet so ready to come to his relief. A muscle like this is worth protecting.


Preparing the Student

Before performing a rectal examination of the patient, you should have acquired some minimum physical skills that will permit you to conduct your examination causing as little discomfort and pain as possible. In bygone days, it was expected that all the medical students would have performed rectal examinations on each other before being set loose on patients. The type of diligent preceptorship requisite to such an activity is now as rare as a xebec.

Similarly, medical schools previously had a required proctology rotation. Among other educational opportunities, this included the chance to perform (with the patient’s prior permission) a rectal examination on an anesthetized patient under the direct supervision of the patient’s personal proctologist who was about to perform surgery.

There are excellent mannequins that will permit the student to gain some initial experience in inserting a lubricated gloved finger through a sphincter and palpating a variety of prostatic prostheses. If your school does not have such a mannequin, volunteers should be solicited from your Curriculum Committee.

Preparing the Patient for Examination

A Method

In the woman, the rectal examination is generally performed as part of the pelvic examination (see Chapter 22). However, in cases in which the pelvic examination has been deferred, the rectal examination can still be done by the method used for the man.

Positioning the Patient

The examination is often performed with the patient standing with his legs spread a few feet apart, leaning forward, his chest resting on the examining table. It is usually more dignified if the patient is lying down, as described below (assuming that a pelvic examination is not being done).

The bed-bound patient can be examined in one of two modified Sims positions, the two differing depending on whether the leg is extended or flexed: The patient may be placed in the left lateral decubitus position, as for a lumbar puncture, with the knees and hips flexed, the trunk flexed forward, and the arms holding the hips and knees in maximum flexion. The second position would be obtained by having the lower (left) leg fully extended at the knee and, more importantly, at the hip. This actually rolls the patient another 45 degrees toward the prone position. Which position is optimum depends on the given patient’s skeletal mobility and/or the obscuring quality of the buttocks.

If the patient is in an immovable supine position, the hips can be flexed, the knees flexed (passively, if need be, and held by an assistant), and the anus thus exposed to the examiner. Although one can do a rectal examination and even obtain stool samples from a patient held in this position, one may not always be completely confident about what one is palpating.

Protecting the Patient’s Dignity

Hand the patient some tissue at this time to hold for later use at the end of the examination and say. “I am going to use some lubricant to make the examination more comfortable for you. I will tell you when I’m done.” (This last statement is made as a part of physicianhood. The patient will know very well when you are done.)

You can also hand the patient the tissue at the end of the examination, but some doctors become so busy with the guaiac test that they forget to do so. Besides, handing the patient the tissue
in the beginning shows the patient that you are sensitive to and anticipate his feelings. Having him hold the tissue makes him a more active participant and less acted upon, a matter that could become exquisitely important in light of the psychodynamics of some male patients.

Dr Douglas Lindsey of Arizona instructs the students to do the wiping (although this does not preclude handing the patient some tissue also) because they are wearing gloves and can discreetly dispose of the tissue. If you do this, tell the patient that you are cleaning off the lubricant. Then ask him to get dressed while you run a test for occult blood. Leave the room, being sure that a box of tissues and a covered wastebasket are conveniently within his reach. Before returning, allow the patient sufficient time to restore his dignity and wash his hands if he likes.

Do not forget to explain to the patient why he is being subjected to this examination in the first place! (“I’m checking for cancer or internal bleeding,” for example.) In a survey conducted at the University of Minnesota, one third of patients said the internal medicine resident did not explain the reason for the rectal examination, and 41% of those who preferred to be offered tissue said they received some other type of postexamination care (Wilt and Cutler, 1990).


  • Put your gloves on, spread the patient’s cheeks, and examine for external hemorrhoids, tumors, condylomata, ulcers, fissures, excoriations, prolapsing internal hemorrhoids, or anything that you have never seen before. You will probably fail to see a fissure if you do not spread the cheeks and put a little bit of stretch on the anus.

    Dr Frank Iber of Illinois adds: You can gain a great deal of information from inspection prior to the rectal examination. If the person, with a little straining, can show you the margin between the skin and the mucosa, this will reveal external hemorrhoids and skin irritation. If he is unable to relax sufficiently to show you this margin, it may indicate pathology that can be encountered with the finger or anoscope.

    While performing this part of the examination, you might also want to check the patient for the anal wink (see Chapter 26). Although an absent anal wink is sometimes observed in the presence of a large fecal impaction, persistence after disimpaction suggests a neurologic impairment (Whitehead et al., 2000).

    If the anal sphincter gapes open on parting the buttocks or exerting traction on the anal canal, neurologic or anatomic injuries should be suspected.

  • Put a generous amount of lubricant on your gloved index finger and say, “I am going to put some lubricant on you now. It might feel cold.”

  • Place the lubricant at the anal orifice. If the patient has asked whether this is going to hurt, you should say, “No, it will be uncomfortable but it shouldn’t produce a pain in the sense of being a sharp sensation. If I do anything during the examination that makes you feel a sharpness, or a pain, be sure to tell me.”

    If the patient has not raised this issue, at this point you should say, “This might feel a little uncomfortable,” or “You’ll feel a pressure.” (Do not call it a “pain.”) Depending on the individual patient, you might add, “But it shouldn’t be painful.” You want to encourage him to report any such sharp painful sensation because it is a clue to the presence of a mucosal tear, a prostatic inflammation, or a rectal abscess. The patient may also be forewarned that there might be a false sensation of being about to have a bowel movement.

  • At this point, it is assumed that you have practiced the rectal examination on a mannequin or an anesthetized patient. Accordingly, you may have become inappropriately cavalier about the rectal sphincter. Gently press the tip of your index finger through the center of the sphincter so that the entire circumference of your finger is coated with lubricant. Note the anal sphincter tone.

  • Insert the examining finger as far as possible and prepare to sweep the four quadrants searching for abnormalities (vide infra).

  • Finally, ask the patient to perform a Valsalva maneuver (“bear down as if having a bowel movement”) so that you can make a final check of the lumen, feeling for polyps and other masses, and the farthermost rectal mucosa. Say “we’re almost done” or words to that effect.

  • Withdraw the examining finger and inspect it for stool. Note its appearance, and place a smear on a slide for occult blood testing or sometimes for other tests such as stool fat stains (see Chapter 28). If you wipe off the lubricant, dispose of the tissue paper inside the glove, which you should turn inside out as you remove it.



Fissures or Fistulae

The presence of a perianal fistula and/or fissure suggests that a patient with inflammatory bowel disease has Crohn regional enteritis rather than chronic ulcerative colitis.

Pilonidal Sinus

Although often misdiagnosed as a “fistula in ano,” a pilonidal sinus is actually located some distance away from the anus, in the midline near the base of the coccyx. Purulent fluid may be expressed by pressure over the sacrum (Clain, 1973).

Skin Lesions

Pruritus ani, with erythema and lichenification of the perianal skin, may result from a variety of causes, such as sensitivity to various foods, condiments, coffee, drugs, irritants in toilet tissue and undergarments, and topical preparations used to treat itching. A symmetric pink discoloration is said to be characteristic for sensitivity to dairy proteins (Friend, 1987). Parasitic infestations (most commonly pinworms) and fungal infections (such as Candida or tinea; Fig. 23-1) are also a possibility. Be attentive for evidence of sexually transmitted diseases such as chancre (see Table 21.1), which may present in the perianal region rather than on the genitalia, especially in homosexual
men. Genital warts (condyloma acuminata) may occur perianally and also inside the anal canal. These may be sexually transmitted, but autoinoculation and fomite transmission also occur (Bays and Chadwick, 1993). Ruling out fomite transmission is very difficult because the incubation period may be years long (Paul, 1990).

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Aug 10, 2020 | Posted by in GENERAL & FAMILY MEDICINE | Comments Off on The Rectum

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